BE1028157B9 - Device and method for determining, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual - Google Patents

Abstract

The present invention relates to a device and to a method for determining/for demonstrating, from a sample previously taken from an individual, in particular from a liquid sample previously taken from an individual, that at least a target antibody has been or is present in said individual.

Description

Device and method for determining, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual The present invention relates to a device and a method for determining / for implementing evidence, from a sample previously taken from an individual, in particular from a liquid sample previously taken from an individual (animal or human), that at least one target antibody has been or is present in said individual ( animal or human).

By the terms “target antibody”, it is understood, within the meaning of the present invention, an antibody which it is sought to know, in particular indirectly, whether it is or has been present in an individual from which a sample is taken beforehand.

A device according to the invention finds numerous applications in the fields of health, in particular for demonstrating/for determining, in an individual from whom a sample is simply taken, that at least one target antibody has been or is present in said individual, this indicating that the individual is subject or has been subject to one or more pathologies or to one or more given diseases. It may for example be a pathology or a viral disease (viral hepatitis, etc.) or a pathology or a bacterial disease (meningitis, etc.) or even a pathology or a parasitic disease (malaria, etc.).

Unfortunately, currently, highlighting / detection devices to highlight / to determine that at least one target antibody has been or is present in an individual, are complex, as are the current methods implemented to evidence / to determine that at least one target antibody has been or is present in an individual.

In addition, generally, the current devices and methods are not very adequate or even totally unsuitable for such demonstrations/detections of at least one target antibody in an individual that must be carried out in the field.

Furthermore, current devices generally require pre-treatment / preparation of the sample taken from an individual, which

? BE2021/5266 still requires the implementation of many reagents. Thus, with current devices, the operator must not only have equipment (reagents, solvents, pipettes, heating device, etc.) but also carry out many delicate manipulations such as dilutions which must be precise. It is obvious that this is particularly restrictive and all the more so in the field where it is sometimes even quite simply impossible to ensure correct preparation of the sample taken. Also, the reagents used are generally sensitive to environmental conditions (high temperatures, humidity, etc.) and/or dangerous to handle, which makes the uses of current devices all the more restrictive.

There is therefore currently a real need to provide a device and a simpler method for demonstrating/for determining that at least one target antibody has been or is present in an individual, in particular when such demonstration/detection must be carried out in the field.

To solve these problems at least in part, provision is made, according to the invention, for a device for determining/for demonstrating, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual, said device comprising: e a molecule or a compound, in particular a molecule or a compound exhibiting oxidation-reduction properties, capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least a target antibody or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody; and e electrodes arranged to be in contact with said sample while the latter is in contact or after the latter has been in contact with said molecule or with said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody.

Within the meaning of the present invention, the electrodes constitute a means of detection, that is to say a part or zone of the device which alone or in association with an external device/equipment (not forming an integral part of the device) according to the invention), to carry out an electrochemical measurement making it possible to determine/deduce that at least one target antibody has been or is present in an individual from whom a sample has been taken beforehand.

By the terms "a molecule or a compound capable of binding to a messenger RNA (mRNA) or to a complementary DNA (cDNA)", it is understood, within the meaning of the present invention, any molecule or any compound which can bind / graft or bind to messenger RNA (mRNA) or complementary DNA (cDNA). It may for example be a molecule or a compound capable of attaching / grafting to the surface of said mRNA or a molecule or a compound interacting according to any other mechanism with said messenger RNA (mRNA) . By way of example, it may also be a molecule or a compound capable of intercalating (we then speak of an intercalating agent) between molecules, in particular between two base pairs, of DNA complementary (cDNA) when it is double-stranded. Such a molecule or such a compound makes it possible to label/target, within a sample taken beforehand from an individual, a messenger RNA (mRNA) or a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region encoding the target antibody. Still by way of example, it can also be a non-intercalating molecule or a non-intercalating compound, such as for example Os(bpy)s**; Ru(NHs)es3; FcCH2N+Me3 or FcB(OH)2. For example, when said molecule or said compound capable of binding to a messenger RNA (mRNA) or to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) is an intercalating agent, it may be methylene, methylene green, brilliant cresyl blue, toluidine blue or even thionine acetate. This list is not exhaustive.

Preferably, according to the invention, said molecule or said compound, in particular said molecule or said compound exhibiting oxidation-reduction properties, capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, is a molecule or a compound capable of interacting with said electrodes, in particular with an electrode of work.

In particular, according to the invention, said molecule or said compound capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained at the start said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is capable of interacting not only with said messenger RNA (mRNA) or capable of binding with said complementary DNA (cDNA) obtained from said messenger RNA (mRNA ) but also with the electrodes.

In practice, said molecule or said compound capable of binding to a messenger RNA (mRNA) or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA), in particular said molecule or said compound capable of to bind to a messenger RNA (mRNA) or to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) and having oxido-reductive properties, is able to exchange electrons with the electrodes, in particular with an electrode of work, which directly determines the magnitude of a signal measured by electrochemistry. If messenger RNA (mRNA) comprising a region coding for said at least one target antibody or if complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is present in the sample, a bond is established between said messenger RNA (mRNA) or said complementary DNA (cDNA) and a certain quantity of molecule or compound such that a lesser quantity of said molecule or said compound is able to interact with the electrodes, in particular with the working electrode, which results in a reduction in the magnitude of the signal measured by electrochemistry. This decrease in the magnitude of the signal measured by electrochemistry makes it possible to determine/deduce that at least one target antibody has been or is present in an individual from whom a sample was previously taken.

> BE2021/5266 According to the invention, for a given messenger RNA (mRNA) comprising a region coding for said at least one target antibody, said molecule or said compound, in particular said molecule or said compound exhibiting oxidation-reduction properties, can either bind directly to messenger RNA (mRNA) comprising a region coding for said at least one target antibody, or bind to a single-stranded or double-stranded complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region encoding said at least one target antibody. In other words, according to an embodiment according to the invention, said molecule or said compound can bind directly to messenger RNA (mRNA) without the latter being subjected to reverse transcription and/or amplification. .

For example, for [establishment of a direct bond between said molecule or said compound and said messenger RNA (mRNA), said molecule or said compound, in particular said molecule or said compound having oxidation-reduction properties, can be a molecule not intercalating or a non-intercalating compound (non-intercalating agent) selected from the group consisting of Os(bpy)3?; Ru(NHzs)e**; FcCH2zN*Mes; FcB(OH)2 and mixtures thereof. This list is not exhaustive.

Such a device according to the invention, while being simple, makes it possible to demonstrate/determine by electrochemical measurement, in particular indirectly, from a sample previously taken from an individual, that at least one target antibody was or is present in this individual, in a rapid, precise, reproducible and reliable manner.

The device according to the invention is therefore a device making it possible to demonstrate/determine, in particular indirectly, that at least one target antibody has been or is present in an individual, this from a sample taken beforehand. in this individual, by binding or not of a compound or of a molecule to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or by binding or not of a compound or of a molecule to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for the target antibody, and by determining, through at least one electrochemical measurement, the establishment or not of this bond between said messenger RNA (mRNA) and said molecule or said compound or by determining, through at least one electrochemical measurement, the establishment or not of this bond between said complementary DNA (cDNA) and said molecule or said compound.

A device according to the invention makes it possible more particularly to quickly determine which antibody(ies) carries/has carried an individual (target antibody), this on the basis of the determination of the establishment or not of a bond between a messenger RNA (mRNA ) comprising a region coding for said at least one target antibody and said molecule or said compound or on the basis of the determination of the establishment or not of a bond between a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) and comprising a region encoding said at least one target antibody and said molecule or said compound. Advantageously, the device according to the invention intrinsically comprises said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA ) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. In this way, the sample taken from an individual does not require pretreatment / preparation before its introduction into the device, only lysis of the sample being sometimes but not necessarily necessary according to certain embodiments according to the invention, the device according to the invention intrinsically comprising said molecule or said compound capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained at the start said messenger RNA (mRNA) comprising a region encoding the target antibody. By definition, the term “intrinsically” means “which is inherent in something, which belongs to it in its own right”. In the context of the present invention, the term “intrinsically” applied to the device according to the invention therefore means that the device comprises, even before its use and therefore before introduction of a sample, inherently and in its own way the compounds/constituents indicated as being present therein intrinsically.

The device according to the invention allows the operator to dispense with a large quantity of equipment and reagents but also to considerably reduce the manipulations to be carried out, in particular in the field, to highlight/to determine, from a sample taken from an individual, that at least one target antibody has been or is present in that individual. The result is in particular that handling errors and contamination are significantly reduced, that the measurements carried out are all the more reliable and that the time required to carry out a detection, in particular in the field, is significantly reduced. In addition, a device according to the invention is inexpensive and compact since it does not require large equipment such as those used in the laboratory.

In other words, a device according to the invention makes it possible, in a simple, rapid, precise, reproducible and reliable manner, to demonstrate/determine that at least one target antibody has been or is present in an individual by determining the establishment or otherwise of a bond between a specific mRNA or a cDNA obtained from said specific mRNA corresponding to the target antibody and a molecule or a compound capable of binding to said mRNA or said cDNA obtained from said mRNA comprising a region coding for said at least one target antibody.

Preferably, according to the invention, said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is in anhydrous or lyophilized form.

Unlike a liquid form (for example an aqueous form), an anhydrous or freeze-dried form makes it possible to have a device which can be stored for several months or even several years without degradation of the molecule or of the compound capable of binding to a Messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for the target antibody, said molecule or said compound retaining its properties over time, which contributes to reproducibility of the results.

Currently, a liquid form of such a molecule or such a compound is recommended, in particular a liquid form of such a molecule or such a compound introduced into the device after introduction into the latter of a sample (the molecule or compound is therefore not intrinsically present in the device). With current devices, this liquid form is systematically used and recommended to ensure the availability of said molecule or said compound.

Unlike current devices and advantageously according to the present invention, the molecule or compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is present in a device according to the invention in a non-liquid form, in particular in an anhydrous or lyophilized form. It has been shown, in the context of the present invention and contrary to what is recommended and encountered with current devices, that this non-liquid form, in particular this anhydrous or freeze-dried form, makes it possible to ensure a binding between said molecule or said compound and a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or between said molecule or said compound and a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, to demonstrate/to determine, in an individual from whom a sample is simply taken, that at least one target antibody has been or is present in said individual.

In practice, when the molecule or compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA) obtained from said RNA messenger (mRNA) comprising a region coding for said at least one target antibody, in anhydrous or lyophilized form is intrinsically present in a device according to the invention, it is put into solution by the sample itself -even following its introduction into the device.

Preferably, according to the invention, said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA) obtained at departure of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is present on a support, for example on a cellulosic support, comprising positive charges and/or positively charged groups and/or polymers positively charged.

For example, positively charged groups are associated with a support, in particular with a cellulosic support, by covalent or other grafting.

Alternatively or additionally, positively charged polymers are associated with a support, in particular with a cellulosic support, paradsorption.

Alternatively or additionally, predetermined chemical species are polymerized on the surface of a support, in particular on the surface of a cellulosic support, so that positively charged polymers are associated with this support.

In the context of the present invention, it has been put forward that such a positively charged support makes it possible to guarantee adequate availability of said molecule or of said compound capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for the target antibody, in the sense that said molecule or said compound does not remain attached ( e) to the support in order to be able to bind to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or to be able to bind to a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region encoding the target antibody so as to ensure adequate electrochemical measurements.

According to a preferred embodiment according to the invention, the device according to the invention intrinsically comprises said electrodes.

According to one embodiment, the device according to the invention further comprises: e reagents allowing reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or reagents allowing performing amplification to obtain amplicons of said messenger RNA

(mRNA) comprising a region coding for said at least one target antibody, and, optionally, a heating element, for example a heating element comprising an electrical resistor, arranged to heat said sample while the latter is in contact or after this last has been in contact with said reagents allowing the realization of the reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or with said reagents allowing the realization of the amplification of said messenger RNA (mRNA ) comprising a region coding for said at least one target antibody.

According to the invention, the device may or may not include an electric heating element, in particular may or may not intrinsically comprise an electric heating element.

When it does not include an electric heating element, the heating of the device can be ensured, for example, by bringing the device into contact with a heating plate or with any other device making it possible to ensure heating of the sample while the latter is in contact or after the latter has been in contact with said reagents allowing the reverse transcription and/or amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody to be carried out.

According to one embodiment, the device according to the invention therefore makes it possible to carry out reverse transcription and/or amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody.

Reverse transcription techniques for RNA, in particular messenger RNA (mRNA), are well known to those skilled in the art.

RNA amplification techniques, in particular messenger RNA (mRNA) are also well known to those skilled in the art.

In particular and by way of example, the PCR, RT-PCR, LAMP and RT-LAMP amplification techniques are techniques well known to those skilled in the art who are therefore able to determine, for messenger RNA (mRNA ) given, which reagents and which quantities of reagents must be used (for example:

H BE2021/5266 buffers, dNTPs, polymerase, DNA polymerase, primers, reverse transcriptase, etc.). By way of example and not exhaustive, can be implemented as reagents allowing the realization of a reverse transcription and / or an amplification of the messenger RNA (mRNA) to obtain amplicons, a transcriptase reverse or reverse transcriptionase, a polymerase, a DNA polymerase, primers, dNTPs and/or buffers. By way of example, to carry out the amplification of messenger RNA (mRNA) to obtain amplicons, a reverse transcriptase or retrotranscriptase and/or a DNA polymerase can be implemented as reagents.

Reverse transcriptase or retrotranscriptase is an enzyme used to perform transcription in the reverse of the standard direction (reverse transcription or retrotranscription) to obtain DNA from RNA.

Reverse transcriptase therefore makes it possible, starting from RNA, to use amplification techniques such as polymerase chain reaction (PCR) or loop-mediated isothermal amplification (LAMP) conventionally carried out using DNA strands.

In other words, using reverse transcriptase, RNA can be transcribed into DNA, making RNA analysis feasible using conventional DNA amplification techniques.

When reverse transcriptase or retrotranscriptase is associated with the PCR amplification technique, it is then referred to as polymerase chain reaction by reverse transcriptase (RT-PCR). When the reverse transcriptase or retrotranscriptase is associated with the LAMP amplification technique, we then speak of isothermal amplification mediated by reverse transcription loop (RT-LAMP). Note that reverse transcriptase makes it possible to create complementary DNA (cDNA) from mRNA.

cDNA is a single strand synthesized from an mRNA, thus representing the coding part of the region of the genome that has been transcribed into this mRNA.

cDNA is obtained after a reverse transcription reaction of an mRNA and hence is equivalent to the DNA copy of mRNA.

Double-stranded cDNA can result from the copying of a first strand by a DNA polymerase.

According to the invention, said complementary DNA (cDNA) can be single-stranded or double-stranded. Advantageously, the device according to the invention intrinsically comprises said reagents allowing said reverse transcription of said messenger RNA (mRNA) to be carried out comprising a region coding for said at least one target antibody and/or said reagents allowing said amplification of said messenger RNA to be carried out (mRNA) comprising a region coding for said at least one target antibody. Preferably, according to the invention, said reagents allowing said reverse transcription of said messenger RNA (mRNA) to be carried out comprising a region coding for said at least one target antibody and/or said reagents allowing said amplification of said messenger RNA (mRNA) to be carried out ) comprising a region coding for said at least one target antibody are in anhydrous or lyophilized form.

Currently, a liquid form of the reagents allowing the realization of a reverse transcription and/or an amplification is recommended, in particular a liquid form of the reagents allowing the realization of a reverse transcription and/or an amplification introduced within of the device after introduction into the latter of a sample (the reagents enabling reverse transcription and/or amplification to be carried out are therefore not intrinsically present in the device). With the current devices, this liquid form of the reagents allowing the realization of a reverse transcription and/or an amplification is systematically used and recommended to ensure the availability for a transcription and/or for a correct amplification and reliable can be carried out since the reagents allowing the realization of a reverse transcription and/or an amplification must be able to interact with the messenger RNA (mRNA).

Unlike the current devices and advantageously according to the present invention, the reagents allowing the realization of a reverse transcription and/or the realization of an amplification are present in a device according to the invention in a non-liquid form, in particular in a anhydrous or freeze-dried form. It has been shown, in the context of the present invention and contrary to what is recommended and encountered with current devices, that this non-liquid form, in particular this anhydrous or lyophilized form, of the reagents allowing the production of a reverse transcription and/or the realization of an amplification makes it possible to carry out a transcription and/or a correct and reliable amplification to highlight / to determine, in an individual from whom a sample is simply taken, that at the least one target antibody has been or is present in said individual. In other words, against all expectations, it has been demonstrated in the context of the present invention that a non-liquid form of the reagents allowing the realization of a reverse transcription and/or the realization of an amplification, in particular that an anhydrous or freeze-dried form of the reagents allowing the realization of a reverse transcription and/or the realization of an amplification, makes it possible to carry out a precise and reliable reverse transcription and/or amplification to highlight / to determine , in an individual from whom a sample is simply taken, that at least one target antibody has been or is present in said individual.

In practice, when the reagents allowing the realization of a reverse transcription and/or the realization of an amplification are in anhydrous or lyophilized form and are intrinsically present in a device according to the invention, they are dissolved by the sample itself following its introduction into the device.

Preferably, according to the invention, said reagents allowing said reverse transcription of said messenger RNA (mRNA) to be carried out comprising a region coding for said at least one target antibody and/or said reagents allowing said amplification of said messenger RNA (mRNA) to be carried out comprising a region coding for said at least one target antibody are present on a support, for example on a cellulosic support, comprising positive charges and/or positively charged groups and/or positively charged polymers. The advantages of such support are mentioned above.

Advantageously, the device according to the invention further comprises a reagent for lysing said sample or a solution for lysing said sample.

Preferably, according to the invention, said reagent for lysing said sample is in anhydrous or freeze-dried form. The advantages of such an anhydrous or freeze-dried form are identical to those mentioned above.

Advantageously, the device according to the invention is in the form of a cartridge or a microfluidic device, for example in the form of a cell or a microfluidic chip or a paper-based microfluidic device.

Advantageously, according to the invention, said molecule or said compound capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained from said Messenger RNA (mRNA) comprising a region coding for the target antibody comprises/is means for labeling said at least one of messenger RNA (mRNA) comprising a region coding for said at least one target antibody or means for labeling said DNA complementary (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for the target antibody.

By the terms "means for labeling said messenger RNA (mRNA) or said complementary DNA (cDNA)", it is understood, within the meaning of the present invention, a means making it possible to mark / target the messenger RNA (mRNA) or the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) so as to distinguish it among the various compounds/constituents of a sample taken from an individual.

Preferably, according to the invention, said marking means is in anhydrous or freeze-dried form.

Advantageously, the device according to the invention intrinsically comprises said marking means.

According to an embodiment according to the invention, said marking means is an intercalating agent, in particular an intercalating agent having oxido-reducing properties.

According to the invention, the intercalating agent, in particular the intercalating agent having redox properties, can be methylene blue, methylene green, brilliant cresyl blue, toluidine blue or even thionine acetate. This list is not exhaustive and any other suitable intercalating agent falls under the scope of the present invention.

Advantageously, the device according to the invention intrinsically comprises said intercalating agent.

According to another embodiment according to the invention, said labeling means is a non-intercalating agent, in particular a non-intercalating agent having oxidation-reduction properties.

Advantageously, the device according to the invention intrinsically comprises said non-intercalating agent. Preferably, according to the invention, said electrodes are arranged to be electrically accessible from outside said device. Advantageously, the device according to the invention intrinsically comprises said reagent for lysing said sample. Preferably, according to the invention, said sample is a sample chosen from a blood sample, a saliva sample, a urine sample. According to one embodiment, the device according to the invention has: e a first part or zone comprising said reagents allowing the performance of a reverse transcription and/or the performance of an amplification of the said mRNA comprising a region coding for the said at least a target antibody, to obtain amplicons; and e a second part or zone comprising said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to complementary DNA (cDNA) obtained at the start of said messenger RNA (mRNA) comprising a region coding for the target antibody, in particular a second part or zone comprising a labeling means capable of binding to the messenger RNA (mRNA) comprising a region coding for the said at least a target antibody or capable of binding to the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for the target antibody, more particularly a second part or zone comprising an intercalating agent exhibiting oxido properties -reductive and capable of being inserted between molecules of said amplicons.

A distinction between these two parts or zones makes it possible to sequence the steps of reverse transcription and/or amplification and binding of the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least a target antibody. This allows the device according to the invention to be optimal, amplicons being first obtained before they come into contact with said molecule or said compound capable of binding to a complementary DNA (cDNA) obtained from said Messenger RNA (mRNA) comprising a region encoding the target antibody. Advantageously, the device according to the invention comprises a valve situated between said first part or zone and said second part or zone. The presence of a valve makes it possible to control the passage of the sample, lysed or not, from the first part to the second part after a determined period of residence of the sample in the first part so that the reverse transcription and/or the amplification to obtain amplicons is/are optimized. Advantageously, the device according to the invention has an additional part or zone comprising a reagent for lysing said sample or said solution for lysing said sample, said additional part or zone being located upstream of said first part and of said second part in a direction sample flow/displacement. Depending on the type of sample taken from an individual, it may be useful to lyse the sample. In order to prevent the operator from carrying out a lysis in the field with specific and cumbersome equipment (pipette, lysis solution, etc.), the device according to the invention can advantageously comprise a lysis chamber (part or additional zone) in which the sample is lysed before reaching the other parts or zones of the device. Preferably, the device according to the invention comprises a valve situated between said additional part or zone and said first part or zone and/or said second part or zone. The presence of such a valve makes it possible to control the passage from the part or additional zone where the lysis of the sample takes place towards the first and/or the second part after a determined period of residence of the sample in this part or additional area such that sample lysis is optimized.

Advantageously, the device according to the invention is in the form of a cartridge through which a solution or a microfluidic device can flow, for example in the form of a cell or a microfluidic chip. The device according to the invention can also take the form of a paper-based microfluidic device (“paper-based microfluidics”) consisting for example of a series of hydrophilic cellulose or nitrocellulose fibers which guide a liquid from one entry to a desired area by imbibition and/or capillary action. Optionally, the paper-based microfluidic device according to the invention is in the form of an origami ("paper-origami based"), that is to say in the form of a microfluidic paper of which parts are intended to be folded one on the other or on each other to be brought into contact. Within the meaning of the present invention, the device can preferably also be in the form of a “paper-based point-of-care NAATs (Nucleic acid amplification-based tests)”.

By way of example, in particular if the device according to the invention is in the form of a chip or a microfluidic cell, the two parts or zones can be distinct chambers fluidically connected (as illustrated in FIGS. 7C and 7D ) or can be separate locations within a single (micro-)channel of a microfluidic chip or cell (as shown in Figure 7F).

According to one embodiment, there is provided, according to the invention, a device for demonstrating the presence of at least one target antibody in an individual, starting from a sample, said device comprising: - reagents allowing the carrying out an amplification of messenger RNA (mRNA) comprising a region coding for said at least one target antibody; - a heating element arranged to heat said sample while the latter is in contact or after the latter has been in contact with said reagents allowing the amplification of said mRNA to be carried out; and - a means for detecting said amplified mRNA.

Advantageously, according to the invention, said reagents allowing the realization of an amplification of said mRNA, and/or said reagents for lysing said sample are in anhydrous or lyophilized form. Preferably according to the invention, said reagents allowing amplification to be carried out and/or said intercalating agent having redox properties and/or said reagents for lysing said sample and/or said intercalating agent are in the form of a lyophilisate in the device according to the invention. Preferably, according to the invention, said reagents allowing the realization of an amplification of said mRNA, and/or said intercalating agent are present on a support, for example on a cellulosic support, comprising positive charges and/or positively charged groups and / or positively charged polymers.

Preferably, according to the invention, said electrical heating element comprises an electrical resistor, which is powered by a source of electrical energy.

The present invention also relates to an assembly comprising: e a device according to the invention; and e an apparatus or apparatus capable of being electrically connected to the electrodes to perform electrochemical measurements, preferably electrochemical voltammetric measurements, more preferably cyclic electrochemical voltammetric measurements or square waves.

Typically, to carry out electrochemical measurements, preferably electrochemical voltammetric measurements, more preferably cyclic or square wave electrochemical voltammetric measurements, the apparatus comprises a potentiostat for applying a potential difference between the electrodes and/or a processing unit of signals emitted by the potentiostat or received by the potentiostat.

The present invention also relates to a method for determining/for demonstrating, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual, said method comprising: first step of bringing the sample into contact with a molecule or with a compound, in particular with a molecule or with a compound having oxido-reducing properties, to ensure a bond between said molecule or said compound and a messenger RNA (mRNA ) comprising a region coding for said at least one target antibody or for ensuring a connection between said molecule or said compound and a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody ; and e a second step of bringing said sample into contact with electrodes electrically connected to an apparatus or to an apparatus to carry out at least one electrochemical measurement, simultaneous or delayed in time with respect to said first step, to determine whether a bond is / has been established between said messenger RNA (mRNA) and said molecule or said compound or to determine whether a link is/has been established between said complementary DNA (cDNA) and said molecule or said compound and to deduce therefrom that at least one target antibody was or is present in said individual.

According to one embodiment of the process according to the invention, the first step of bringing into contact is a step of direct binding of said molecule or of said compound, in particular of said molecule or of said compound having oxidation-reduction properties, to an RNA messenger (mRNA) … comprising a region coding for said at least one target antibody.

By the terms "direct bond", it is understood, within the meaning of the present invention, that the bond is established between said molecule or said compound and said messenger ARM (mRNA) without the latter undergoing any modification, in particular without that the latter does not undergo reverse transcription and/or amplification.

According to another embodiment of the method according to the invention, the first contacting step is a step of binding said molecule or said compound, in particular said molecule or said compound having oxido-reducing properties, to Complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, said messenger RNA (mRNA) being subjected/having been subjected to reverse transcription and/or amplification.

Indeed, according to the invention, for a given messenger RNA (mRNA) comprising a region coding for said at least one target antibody, said molecule or said compound, in particular said molecule or said compound having oxidation-reduction properties, can either bind directly to messenger RNA (mRNA) comprising a region coding for said at least one target antibody, or bind to a single-stranded or double-stranded complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. In other words, according to an embodiment according to the invention, said molecule or said compound can bind directly to messenger RNA (mRNA) without the latter being subjected to reverse transcription and/or amplification. . For example, said molecule or said compound which can bind directly to messenger RNA (mRNA), in particular said molecule or said compound which can bind directly to messenger RNA (mRNA) having oxidation-reduction properties, can be a non-intercalating molecule or non-intercalating compound (non-intercalating agent) selected from the group consisting of Os(bpy)s**; Ru(NHs)s3; FcCHeN*Mes; FcB(OH)a and mixtures thereof. This list is not exhaustive.

Advantageously, the method according to the invention further comprises: e a third step of bringing said sample into contact, simultaneous or delayed in time with respect to said first step and/or with respect to said second step, with reagents allowing the carrying out a reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or with reagents allowing the carrying out of an amplification to obtain amplicons of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, and e heating said sample, using a heating element, to heat said sample while the latter is in contact or after the latter has been in contact with said reagents allowing carrying out a reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or with said reagents allowing the re carrying out an amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody.

When said molecule and said compound and/or when said reagents allowing reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or when said reagents allowing amplification to be carried out to obtain amplicons of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, are intrinsically present in a device according to the invention in anhydrous or lyophilized form, the sample by passage in/through the device, dissolves said molecule or said compound and/or said reagents.

Preferably, the method according to the invention comprises a prior step of introducing said sample into a device according to the invention or into a device of an assembly according to the invention, said device preferably comprising intrinsically said molecule or said compound, in in particular said molecule or said compound having redox properties.

Preferably, according to the invention, said amplification of said at least one messenger RNA (mRNA) comprising a region coding for said at least one target antibody is an amplification carried out according to the reverse transcriptase polymerase chain reaction technique ( RT-PCR) or by the technique of isothermal amplification mediated by reverse transcription loop (RT-LAMP) or according to any other suitable amplification technique.

According to one embodiment, the method according to the invention comprises: - a step of introducing said sample into a device according to the invention or into a device of an assembly according to the invention; - a first step of bringing said sample into contact, within said device, with reagents intrinsically present in said device to carry out an amplification of said at least one messenger RNA (mRNA) to obtain amplicons of said at least one messenger RNA (mRNA) ; - a second step of bringing into contact, within said device, during or after said first bringing into contact, said sample with an intercalating agent intrinsically present in said device, in particular with an intercalating agent intrinsically present in said device and having properties oxidation-reduction, to achieve an intercalation of said intercalating agent between molecules of said amplicons, in particular an intercalation of said intercalating agent in a space between two base pairs of said amplicons; - a third step of bringing into contact, within said device, during or after said first bringing into contact and/or during or after said second bringing into contact, said sample with electrodes electrically connected to a device or to an apparatus for carrying out at least one electrochemical measurement, in order to determine/demonstrate from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual.

Preferably, according to one embodiment, the method according to the invention comprises heating of said sample while the latter is in contact or after the latter has been in contact with said reagents allowing the realization of the amplification of said at least one messenger RNA (mRNA) to obtain amplicons of said at least one messenger RNA (mRNA).

Advantageously, according to one embodiment of the method according to the invention, said first step of bringing into contact and/or said second step of bringing into contact consists of dissolving by said sample said reagents intrinsically present in said device to carry out a amplification of said at least messenger RNA (mRNA) and/or by dissolving said intercalating agent intrinsically present in said device, in particular dissolving said intercalating agent intrinsically present in said device and having redox properties, to produce intercalating said intercalating agent between molecules of said amplicons.

Preferably, the method according to the invention comprises a step of lysis of said sample, preferably a step of lysis of said sample carried out upstream of said first and/or of said second contacting step.

According to one embodiment, the method for determining/for demonstrating the presence of at least one target antibody in an individual, starting from a sample, comprises the following steps: a) bringing said sample with reagents allowing carrying out an amplification of messenger RNA (mRNA) comprising a region coding for said at least one target antibody, to obtain amplicons; and b) detection of said amplicons of said amplified mRNA, using detection means.

Preferably, according to the method according to the invention, said amplification is an amplification carried out according to the polymerase chain reaction (PCR) technique or the loop-mediated isothermal amplification technique (LAMP) or according to any technique of adequate amplification.

Advantageously, the method according to the invention comprises a step simultaneous with step a) or delayed in time with respect to step a) of labeling said amplicons. Labeling of amplicons can allow electrochemical detection.

The present invention also relates to a use of a device according to the invention or of an assembly according to the invention to determine/to demonstrate, starting from a sample previously taken from an individual, that at least one antibody target has been or is present in said individual.

Other characteristics, details and advantages of the invention will emerge from the examples given below, on a non-limiting basis and with reference to the appended figures. Generally, in the figures, similar elements bear the same reference.

Figure 1 illustrates a first example of an embodiment of a device according to the invention.

Figure 2 illustrates a second example of an embodiment of a device according to the invention.

Figure 3 illustrates a third example of an embodiment of a device according to the invention.

Figure 4 illustrates a fourth example of an embodiment of a device according to the invention.

Figures 5A, 5B and 5C are exploded views of exemplary embodiments of devices according to the invention and illustrate the components of different embodiments of a device according to the invention.

Figures 6A, 6B, 6C, 6D and 6E are exploded views of exemplary embodiments of devices according to the invention and also illustrate the components of different embodiments of a device according to the invention.

FIGS. 7A, 7B, 7C, 7D, 7E and 7F further illustrate examples of embodiments of devices according to the invention. Examples FIG. 1 illustrates a first embodiment of a device according to the invention which, as illustrated, comprises a first part or zone 1, a second part or zone 2, electrodes 3 and an electric heating element 4. Optionally, as illustrated by the dotted lines, this embodiment of a device according to the invention can comprise an additional part or zone 5 comprising reagents for lysing the sample or a solution for lysing a sample taken from an individual. FIG. 1 illustrates an example of a device according to the invention which could be in the form of a cartridge or of a microfluidic device, for example in the form of a microfluidic device based on paper (“paper- based microfluidics” or “paper-origami based” or “paper-based point-of-care NAATS”).

The first part or zone 1 comprises reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody, to obtain amplicons of mRNA potentially contained in the sample (for example achieving isothermal amplification mediated by reverse transcription loop). The second part or zone 2 comprises a molecule or a compound capable of binding to the amplicons, for example an intercalating agent, having redox properties and being capable of intercalating between molecules of the amplicons, in particular being capable of intercalate in the space between two base pairs of amplicons.

With such a device according to the invention, the sample taken from an individual is preferably lysed, that is to say dissolved in a lysis solution, before being introduced into the device as indicated by the arrow. When, for example under the effect of gravity, the lysed sample reaches the first part or zone 1, it comes into contact with the reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody, to obtain amplicons (for example the realization of isothermal amplification mediated by reverse transcription loop), in the first part or zone 1 under the effect of heating to a predetermined temperature by the electric heating element 4. Amplicons of mRNA comprising a region coding for the target antibody are thus obtained provided that this mRNA is present in the sample taken from the individual. The amplicons obtained then gain, for example under the effect of gravity, the second part or zone 2 comprising a molecule or a compound capable of binding to the amplicons, for example an intercalating agent, which is inserted between the molecules of the amplicons , in particular between two base pairs of the amplicons.

According to the illustrated embodiment, the electrodes 3 (working electrode, counter-electrode or auxiliary electrode and reference electrode) are in contact with the sample after the latter has been in contact with said reagents allowing the transcription to be carried out reverse and the amplification of said mRNA, to obtain amplicons (for example the realization of an isothermal amplification mediated by reverse transcription loop), and with a molecule or a compound capable of binding to the amplicons, for example with an agent intercalating. The electrodes 3 are also electrically accessible from the outside of the device according to the invention so that they can be electrically connected to an apparatus (not illustrated) making it possible to carry out electrochemical measurements (preferably voltammetric electrochemical measurements, more preferably cyclic or square wave electrochemical voltammetric measurements) using for example a redox indicator (in particular an intercalating agent), the principle and the implementation of such a measurement being well known to those skilled in the art.

When the embodiment illustrated in FIG. 1 also comprises an additional part or zone 5 comprising a solution or reagents for lysing a sample taken from an individual, the sample can be introduced directly into the device at the level of the additional part or zone 5 in which the sample is lysed before reaching, for example under the effect of gravity, the first part or zone 1 then the second part or zone 2.

Another embodiment according to the invention corresponds to that illustrated in FIG. 1 but without a first part or zone 1 (that is to say without reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody) and without an electrical heating element 4. According to this embodiment, in the second part or zone 2, the mRNA is directly linked to a molecule or to a compound, for example to a non-intercalating molecule or to a non-intercalating compound (non-intercalating agent), capable of binding to mRNA comprising a region coding for the target antibody without reverse transcription and without amplification of this mRNA.

Figure 2 illustrates a second embodiment of a device according to the invention. FIG. 2 illustrates an example of a device according to the invention which could be in the form of a cartridge or of a microfluidic device, for example in the form of a paper-based microfluidic device (“paper- based microfluidics” or “paper-origami based” or “paper-based point-of-care NAATS”). The same elements as those illustrated in FIG. 1 are repeated. However, according to the embodiment as illustrated in FIG. 2, the first part or zone 1 and the second part or zone 2 are located at the same level, that is to say in the same zone or the same compartment. For example, a molecule or a compound capable of binding to the amplicons, for example an intercalating agent, located in the second part or zone 2 can coat the side walls of a zone or of a compartment of the device, thus surrounding the first part or zone 1 comprising the reagents allowing the realization of the reverse transcription and the amplification of the said mRNA, to obtain amplicons of the mRNA potentially contained in the sample (for example the realization of an isothermal amplification mediated by loop of reverse transcription). It is not excluded, according to the invention, that the reagents allowing the realization of the reverse transcription and the amplification of the said mRNA and that the said molecule or the said compound capable of binding to the amplicons, for example an intercalating agent, are present as a mixture in the same zone or in the same compartment, which would then comprise said first and said second part or zone.

Figure 3 illustrates a third embodiment of a device according to the invention. FIG. 3 illustrates an example of a device according to the invention which could be in the form of a cartridge or of a microfluidic device, for example in the form of a microfluidic device based on paper (“paper- based microfluidics” or “paper-origami based” or “paper-based point-of-care NAATS”). Unlike the embodiment illustrated in FIG. 1, that illustrated in FIG. 3 comprises an additional part or zone 7 located upstream and in contact with the electrodes 3 in a sample flow direction.

Another embodiment according to the invention corresponds to that illustrated in FIG. 3 but without a first part or zone 1 (that is to say without reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody) and without an electric heating element 4. According to this embodiment, in the second part or zone 2, the mRNA is directly linked to a molecule or to a compound, for example to a molecule not intercalating agent or to a non-intercalating compound (non-intercalating agent), capable of binding to the mRNA comprising a region coding for the target antibody without reverse transcription and amplification of this mRNA.

The embodiment illustrated in FIG. 4 is identical to that of FIG. 3 except for the fact that the heating provided by the electric heating element 4 takes place at the level of the additional part or zone 7 located upstream and in contact with the electrodes 3 in a flow direction of the sample rather than at the level of the first part or zone 1. FIG. 4 illustrates an example of a device according to the invention which could be in the form of a cartridge or a microfluidic device, for example in the form of a paper-based microfluidic device ("paper-based microfluidics" or

“paper-origami based” or “paper-based point-of-care NAATS =”). Figures 5A, 5B and 5C illustrate the components of different embodiments of a device according to the invention.

More particularly, FIGS. 5A, 5B and 5C illustrate the components of a device A according to the invention which is in the form of a cylinder constituting for example a cartridge.

In FIG. 5A, the device A according to the invention comprises a first part consisting for example of a 1+2 permeable disc, for example of a permeable disc made of cellulosic material, comprising both the reagents allowing the production of the reverse transcription and amplification of said mRNA, to obtain mRNA amplicons (for example the realization of an isothermal amplification mediated by reverse transcription loop), and a molecule or a compound capable of binding to the amplicons, for example a intercalating agent.

An electrical heater (not shown) provides heating of the 1+2 permeable disc to a predetermined temperature to ensure amplification of said mRNA to obtain mRNA amplicons (e.g. performing reverse transcription loop mediated isothermal amplification ). According to the embodiment of FIG. 5A, three electrodes 3 are in contact with the sample while the latter is in contact with said reagents allowing the reverse transcription and amplification of said mRNA to be carried out, for obtain amplicons from the mRNA (for example the realization of an isothermal amplification mediated by reverse transcription loop), and with a molecule or a compound capable of binding to the amplicons, for example with an intercalating agent.

In addition, the electrodes 3 are also electrically accessible from outside the device according to the invention so that they can be electrically connected to an apparatus (not shown) making it possible to carry out electrochemical measurements (preferably electrochemical voltammetric measurements , more preferably cyclic voltammetric or square wave electrochemical measurements) using for example a redox indicator (in particular an intercalating agent), the principle and implementation of such a measurement being well known to those skilled in the art.

As illustrated in FIG. 5A, the electrodes 3 of the device A according to the invention can be electrically connected to an apparatus (not illustrated) via a base B or a base provided with connectors. For example, the device A according to the invention can be screwed or clipped onto the base or the base B to ensure adequate contact between the connectors and the electrodes 3.

FIG. 5B is identical to FIG. 5A but the device A illustrated also comprises an additional part or zone 5 comprising reagents or a solution for lysing a sample taken from an individual. In this way, the sample can be introduced directly into the device at the level of the additional part or zone 5 in which the sample is lysed before reaching, for example under the effect of gravity, the part consisting for example of a 1+2 permeable disc comprising both the reagents allowing the realization of the reverse transcription and the amplification of the said mRNA, to obtain amplicons of the mRNA (for example the realization of an isothermal amplification mediated by loop of reverse transcription), and a molecule or a compound capable of binding to the amplicons, for example an intercalating agent.

FIG. 5C is identical to FIG. 5B but the device A illustrated additionally comprises a valve 6, for example a rotary slide valve, making it possible to control the passage of the sample from the part or additional zone 5 where it is lysed towards the part consisting for example of a 1+2 permeable disc comprising both the reagents allowing the realization of the reverse transcription and the amplification of the said mRNA, to obtain amplicons of the mRNA (for example the realization of isothermal amplification mediated by reverse transcription loop), and a molecule or a compound capable of binding to the amplicons, for example an intercalating agent.

Other embodiments according to the invention correspond to those illustrated in FIGS. 5A, 5B and 5C but without the presence of reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody and without an electric heating element 4. According to these embodiments, the mRNA is directly linked to a molecule or to a compound, for example to a non-intercalating molecule or to a non-intercalating compound (non-intercalating agent), able to bind to the mRNA comprising a region coding for the target antibody without reverse transcription and amplification of this mRNA.

Figures 6A, 6B, 6C, 6D and 6E also illustrate the components of different embodiments of a device according to the invention. More particularly, FIGS. 6A, 6B, 6C, 6D and GE illustrate the components of a device A according to the invention which is in the form of a cylinder constituting for example a cartridge. In figure GA, the device A according to the invention comprises: - a first part 1 consisting for example of a permeable disk, for example a permeable disk made of cellulosic material, comprising the reagents allowing the realization of the reverse transcription and amplifying said mRNA, to obtain mRNA amplicons (for example performing isothermal amplification mediated by reverse transcription loop); and - a second part 2 consisting for example of a permeable disk, for example a permeable disk of cellulosic material, comprising a molecule or a compound capable of binding to the amplicons, for example an intercalating agent.

An electric heating element (not shown) provides heating of at least the permeable disc 1 to a predetermined temperature to ensure the amplification of said mRNA, to obtain amplicons of the mRNA (for example the realization of an isothermal amplification mediated by reverse transcription loop). According to the embodiment of FIG. 6A, three electrodes 3 are in contact with the sample after the latter has been in contact with said reagents allowing the reverse transcription and amplification of said mRNA to be carried out, to obtain mRNA amplicons (for example the realization of an isothermal amplification mediated by reverse transcription loop), and with a molecule or a compound capable of binding to the amplicons, for example an intercalating agent. In addition, the electrodes 3 are also electrically accessible from outside the device according to the invention so that they can be electrically connected to an apparatus (not shown) making it possible to carry out electrochemical measurements (preferably electrochemical voltammetric measurements , more preferably cyclic voltammetric or square wave electrochemical measurements) using for example a redox indicator (in particular an intercalating agent), the principle and implementation of such a measurement being well known to those skilled in the art. As illustrated in figure GA, the electrodes 3 of the device A according to the invention can be electrically connected to an apparatus (not illustrated) via a base B or a base provided with connectors. For example, the device A according to the invention can be screwed or clipped onto the base or the base B to ensure adequate contact between the connectors and the electrodes 3.

FIG. 6B is identical to FIG. 6A but a valve 6, for example a rotary slide valve, separates the first part 1 from the second part 2 and makes it possible to control the passage of the sample from the first part 1 comprising the reagents allowing the realization of the reverse transcription and the amplification of said mRNA, to obtain amplicons of the mRNA (for example the realization of an isothermal amplification mediated by reverse transcription loop), towards the second part 2 comprising a molecule or a compound capable of binding to amplicons, for example an intercalating agent.

FIG. 6C is identical to FIG. 6A but the device A illustrated also comprises an additional part or zone 5 comprising reagents or a solution for lysing a sample taken from an individual. In this way, the sample can be introduced directly into the device at the level of the additional part or zone 5 in which the sample is lysed before reaching, for example under the effect of gravity, the first part 1 constituted by example of a permeable disk comprising the reagents allowing the amplification of said mRNA to be carried out, in order to obtain amplicons of the mRNA (for example the carrying out of a reverse transcription and of an isothermal amplification mediated by a reverse transcription loop ), then to the second part 2 comprising a molecule or a compound capable of binding to the amplicons, for example an intercalating agent.

FIG. 6D is identical to FIG. 6C but the device A illustrated additionally comprises a valve 6′, for example a rotary slide valve, making it possible to control the passage of the sample from the part or additional zone 5 where it is lysed. to the first part 1 consisting for example of a permeable disc comprising the reagents allowing the realization of the reverse transcription and the amplification of said mRNA, to obtain amplicons of the mRNA (for example the realization of an isothermal amplification mediated by reverse transcription loop) then to the second part 2 comprising a molecule or a compound capable of binding to the amplicons, for example an intercalating agent.

FIG. 6E is identical to FIG. 6D but the device A illustrated additionally comprises a valve 6, for example a rotary slide valve, making it possible to control the passage of the sample from the first part 1 consisting for example of a disc permeable comprising the reagents allowing the realization of the reverse transcription and the amplification of said mRNA, to obtain amplicons of mRNA (for example the realization of an isothermal amplification mediated by reverse transcription loop), to the second part 2 comprising a molecule or compound capable of binding to amplicons, for example an intercalating agent.

Other embodiments according to the invention correspond to those illustrated in FIGS. 6A, GB, 6C, 6D and 6E but without the presence of reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody and without an electric heating element 4. According to these embodiments, the mRNA is directly linked to a molecule or a compound, for example to a non-intercalating molecule or to a non-intercalating compound (non-intercalating agent), capable of binding to mRNA comprising a region coding for the target antibody without reverse transcription and without amplification of this mRNA.

FIGS. 7A, 7B, 7C, 7D, 7E and 7F illustrate examples of embodiments of devices according to the invention in the form of microfluidic devices (cells or microfluidic chips) having an inlet E via which a sample can be introduced. Elements identical to those illustrated in the preceding figures are repeated.

In particular, FIG. 7E illustrates a device according to the invention as illustrated in FIGS. 7A to 7D with the difference that the electrodes are in direct contact with a zone comprising both the reagents allowing the realization of the reverse transcription and amplifying said mRNA to obtain mRNA amplicons (for example performing isothermal amplification mediated by reverse transcription loop) and a molecule or compound capable of binding to the amplicons, for example an agent an agent intercalating.

According to the embodiment of a device according to the invention illustrated in FIG. 7F, the (micro-)channel C of a microfluidic cell or chip constitutes a first zone or part of the device, this first zone or part comprising a first sub-zone (delimited by the dotted lines) where the reagents allowing the realization of the reverse transcription and the amplification of the said mRNA to obtain amplicons of mPARN are found (for example the realization of an isothermal amplification mediated by reverse transcription loop ) and a second sub-zone (delimited by the other dotted lines) where there is a molecule or a compound capable of binding to the amplicons, for example an intercalating agent, each of these two sub-zones being located in the said first zone or part of the device consisting of said (micro-)channel of a microfluidic device and therefore being in fluid communication.

Other embodiments according to the invention correspond to those illustrated in FIGS. 7A, 7B, 7C, 7D, 7E and 7F but without the presence of reagents allowing the realization of a reverse transcription and an amplification of said mRNA comprising a region coding for the target antibody and without an electric heating element 4. According to these embodiments, the mRNA is directly linked to a molecule or a compound, for example to a non-intercalating molecule or to a non-intercalating compound (non-intercalating agent ), capable of binding to mRNA comprising a region coding for the target antibody without reverse transcription and without amplification of this mRNA.

The present invention has been described in relation to specific embodiments, which are purely illustrative and should not be construed as limiting. In general, it will appear obvious to those skilled in the art that the present invention is not limited to the examples illustrated and/or described above.

The use of the verbs "understand", "include", "compose", OR any other variant, as well as their conjugations, can in no way exclude the presence of elements other than those mentioned.

The use of the indefinite article “un”, “une”, or of the definite article “le”, “la” OR “l””, to introduce an element does not exclude the presence of a plurality of these elements.

Claims (16)

Claims 1. Device for determining, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual, said device comprising: e a molecule or a compound, in particular a molecule or a compound having redox properties, capable of binding to a messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to a complementary DNA (cDNA) obtained from said messenger RNA ( mRNA) comprising a region coding for said at least one target antibody; and e electrodes arranged to be in contact with said sample while the latter is in contact or after the latter has been in contact with said molecule or with said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. 2. Device according to claim 1, characterized in that it intrinsically comprises said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. 3. Device according to claim 1 or 2, characterized in that said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of binding to Complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is in anhydrous or lyophilized form. 4. Device according to any one of claims 1 to 3, characterized in that said molecule or said compound capable of binding to messenger RNA (mRNA) comprising a region coding for said at least one target antibody or capable of bind to the complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody is present on a support, for example on a cellulosic support, comprising positive charges and /or positively charged groups and/or positively charged polymers. 5. Device according to any one of the preceding claims, characterized in that it further comprises: e reagents allowing the realization of a reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or reagents allowing amplification to be carried out to obtain amplicons of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody, and, optionally, e a heating element, for example a heating element comprising a electrical resistance, arranged to heat said sample while the latter is in contact or after the latter has been in contact with said reagents allowing the realization of the reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one antibody target and/or with said reagents making it possible to carry out the amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. 6. Device according to claim 5, characterized in that it intrinsically comprises said reagents allowing the realization of said reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and / or said reagents allowing the realization of said amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. 7. Device according to claim 5 or 6, characterized in that the said reagents allowing the realization of the said reverse transcription of the said messenger RNA (mRNA) comprising a region coding for the said at least one target antibody and/or the said reagents allowing the realization of the said amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody are in anhydrous or lyophilized form. 8. Device according to any one of claims 5 to 7, characterized in that said reagents allowing said reverse transcription of said messenger RNA (mRNA) to be carried out comprising a region coding for said at least one target antibody and/or said reagents allowing carrying out said amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody are present on a support, for example on a cellulosic support, comprising positive charges and/or positively charged groups and/or positively charged polymers. 9. Device according to any one of the preceding claims, characterized in that it further comprises a reagent for lysing said sample or a solution for lysing said sample. 10. Device according to claim 9, characterized in that said reagent for lysing said sample is in anhydrous or freeze-dried form. 11. Device according to any one of the preceding claims, characterized in that it is in the form of a cartridge or a microfluidic device, for example in the form of a cell or a microfluidic chip or a paper-based microfluidic device. 12. Assembly comprising: e a device according to any one of claims 1 to 11; and e an apparatus or apparatus capable of being electrically connected to the electrodes to perform electrochemical measurements, preferably electrochemical voltammetric measurements, more preferably cyclic electrochemical voltammetric measurements or square waves. 13. Method for determining, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual, said method comprising: e a first step of bringing the sample into contact with a molecule or with a compound, in particular with a molecule or with a compound exhibiting oxidation-reduction properties, to ensure a bond between the said molecule or the said compound and a messenger RNA (mRNA) comprising a region coding for the said at least one target antibody or to ensure a link between said molecule or said compound and a complementary DNA (cDNA) obtained from said messenger RNA (mRNA) comprising a region coding for said at least one target antibody; and e a second step of bringing said sample into contact with electrodes electrically connected to an apparatus or to an apparatus to carry out at least one electrochemical measurement, simultaneous or delayed in time with respect to said first step, to determine whether a bond is / has been established between said messenger RNA (mRNA) and said molecule or said compound or to determine whether a link is/has been established between said complementary DNA (cDNA) and said molecule or said compound and to deduce therefrom that at least one target antibody was or is present in said individual. 14. Method according to claim 13, characterized in that it further comprises: e a third step of bringing said sample into contact, simultaneous or delayed in time with respect to said first step and/or with respect to said second step , with reagents allowing reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or with reagents allowing amplification to be carried out to obtain amplicons of said messenger RNA ( mRNA) comprising a region coding for said at least one target antibody, and e heating said sample, using a heating element, to heat said sample while the latter is in contact or after the latter has been in contact with said reagents making it possible to carry out a reverse transcription of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody and/or with said reagents allowing the realization of an amplification of said messenger RNA (mRNA) comprising a region coding for said at least one target antibody. 15. Method according to claim 13 or 14, characterized in that it comprises a prior step of introducing said sample into a device according to any one of claims 1 to 11 or into a device of an assembly according to claim 12, said device preferably comprising intrinsically said molecule or said compound, in particular said molecule or said compound having redox properties. 16. Use of a device according to any one of claims 1 to 11 or of an assembly according to claim 12 to determine, from a sample previously taken from an individual, that at least one target antibody has been or is present in said individual.