Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
  • G01N33/577—Immunoassay; Biospecific binding assay; Materials therefor involving monoclonal antibodies binding reaction mechanisms characterised by the use of monoclonal antibodies; monoclonal antibodies per se are classified with their corresponding antigens
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
  • G01N33/543—Immunoassay; Biospecific binding assay; Materials therefor with an insoluble carrier for immobilising immunochemicals
  • G01N33/54306—Solid-phase reaction mechanisms

Definitions

• This invention relates to methods for detecting and/or for determining the concentration of antigenic substances in fluids such as serum and to a kit for use therein. In another aspect it relates to immunometric assay techniques. In yet another aspect it relates to monoclonal and polyclonal antibodies.
• immunoassay techniques are based upon formation of a complex between the antigenic substance being assayed and an antibody or antibodies in which one or the other member of the complex may be labeled, for example, by a radioactive element such as I 125 , which permits its detection and/or quantitative analysis after separation of the complexed labeled antigen or antibody from uncomplexed labeled antigen or antibody.
• the antigenic substance in a sample of fluid being tested for its presence competes with a known quantity of labeled antigen for a limited quantity of antibody binding sites.
• the amount of labeled antigen bound to the antibody is inversely proportional to the amount of antigen in the sample.
• immunometric assays employ a labeled antibody. In such an assay, the amount of labeled antibody associated with the complex is directly proportional to the amount of antigenic substance in the fluid sample.
• Immunometric assays have been found to be particularly well suited for the detection of polyvalent antigens, i.e., antigenic substances that are able to complex with two or more antibodies at the same time.
• Such assays employ a quantity of unlabeled antibody bound to a solid support that is insoluble in the fluid being tested and a quantity of soluble antibody bearing a label such as a radioactive isotope that permits detection and/or a quantitative estimate of the amount of the ternary complex formed between solid phase antibody, antigen, and labeled antibody.
• the body has produced relatively large quantities of antibodies to antigens other than the one of interest such that most of the antibody in the polyclonal mixture is not specific for the antigen of interest. Accordingly, the antibodies used in prior immunometric assays are necessarily "polyclonal" in nature since the antibodies are derived from antisera raised in a conventional manner in animals and their purification is difficult.
• the monoclonal antibody used as the antibody bound to the solid support be the product of a different cell line than is the monoclonal antibody used for the labeled antibody and the two monoclonal antibodies be selected to bind the antigenic substance at sites remote from each other so as to not interfere with the others binding to the antigen.
• an immunometric assay methodology and kit for use therein with the advantages of the monoclonal antibody system of David et al. (high specificity, low cost, and ready availability of antibodies high quantity) as well as the advantages of the polyclonal antibody system of the prior art (high avidity, relatively fast reaction times, and high sensitivity) both present. More particularly, the present invention encompasses a process for asaying the concentrations of an antigenic substance in a fluid comprising the steps:
• the present invention also encompasses a process for the determination of the presence of an antigenic substance in a fluid comprising the steps:
• an improved immunometric assay to determine the presence or concentration of an antigenic substance in a sample of a fluid.
• This assay is of the type comprising forming a ternary complex of a first labeled antibody, the antigenic substance, and a second antibody, the second antibody being bound to a solid carrier insoluble in said fluid wherein the presence of the antigenic substance in the samples is determined by measuring ei >ther the amount of labeled antibody bound to the solid carrier or the amount of unreacted labeled antibody.
• the improvement in the immunometric assay of the present invention comprising employing a labeled antibody selected from a group consisting of monoclonal x and polyclonal (1- ⁇ ) antibodies and an antibody bound to a solid carrier and selected from a group consisting of monoclonal (1- ⁇ ) and ⁇ olyclonal ⁇ antibodies, wherein x is 0 or 1.
• the present invention further encompasses a kit comprising in association:
• a soluble first antibody to an antigenic substance present in a fluid to be assayed the first antibody being labeled and being selected from a group consisting of monoclonal ⁇ and polyclonal (1- ⁇ ) antibodies and
• a second antibody to said antigenic substance the second antibody being bound to a solid carrier and being selected from a group consisting of monoclonal (1- ⁇ ) and polyclonal ⁇ antibodies: wherein x is 0 or 1.
• a monoclonal antibody as either the labeled antibody or the antibody bound to a solid carrier
• a polyclonal antibody as the corresponding bound antibody or labeled antibody, respectively
• the monoclonal antibody is chosen as the antibody bound to the solid carrier
• one polyclonal antibody used in an immunometric assay for an antigenic substance is replaced by a monoclonal antibody.
• antigen or antigenic substance refers broadly to substances to which antibodies can be produced.
• hormones such as insulin and human thyroid stimulating hormone (HTSH), gamma globulins, allergens, viruses, virus subunits, bacteria, toxins such as those associated with tetanus and with animal venoms, and even some drugs.
• thyroid stimulating hormone TSH
• human IgE human CG
• CEA carcinoembryonic antigen
• hepatitis A and B hepatitis Non A/Non B
• IgE alphafetoprotein
• the monoclonal antibodies useful in the present invention are obtained by the process discussed by Milstein and Kohler and reported in Nature, 256 :495-497 (1975). The details of this process are well known and will not be repeated here.
• the monoclonal antibody selected will have an affinity of at least 10 8 liters/mole and, more preferably, an affinity of at least about 10 9 liters/mole. It is also preferred that the polyclonal antibody have an average affinity of at least 10 9 , more preferably 10 10 , liters/mole.
• the monoclonal antibody is selected to be the bound antibody and the polyclonal antibody is selected to be the soluble labeled antibody.
• the reason for this choice is that the amount of solid phase antibody is approximately 1 or 2 orders of magnitude greater than the amount of labeled antibody required in an immunometric assay. Accordingly, this choice enables one to rely on a relatively low cost, readily available monoclonal antibody for the bulk of one's antibody requirements.
• the unlabeled monoclonal antibody or polyclonal used in the present invention to extract the antigenic substance from the sample being tested may be immobilized on any of the common supports used in immunometric assays.
• filter paper plastic beads or test tubes made from nylon, polyethylene polystyrene, polypropylene or other suitable material.
• particulate materials such as agarose, crosslinked dextran, and other polysaccharides.
• the techniques for such bonding are well known to those skilled in the art.
• antibodies may be bound to polysaccharide polymers using the process described in U.S. Patent No. 3,645,852.
• the labeled monoclonal or polyclonal antibody used in the present invention may be provided with the same labels used in prior art immunometric assays. Among these may be mentioned fluorogenic labels for detection by fluorometry as described in U.S. Patent No. 3,940,475 and enzymatic markers as described in U.S. Patent No.
• the amount of labeled antibody associated with the insoluble sandwich complex is determined by examination of the insoluble carrier material by suitable means.
• suitable means it is also possible to relate the presence or absence of antigen in the fluid sample being assayed to the amount of labeled antibody which does not react during the assay and remains in a soluble form.
• the kit of the present invention preferably further comprises a set of standards which will enable one to generate a standard curve. By comparing the value obtained from an unknown sample with the standard curve, one can quantitatively assay the sample.
• kits which contain an enzyme labeled antibody can further optionally comprise an enzyme marker developer for purposes of being able to detect the amount of enzyme present in the phase being assayed.
• Polyclonal antibodies - anti-human IgE serum was produced from goat and purified via affinity chromatography.
• Monoclonal antibodies - monoclonal antibodies for IgE were obtained from a commercial source.
• Bound antibodies - monoclonal antibodies for IgE were covalently bound to polystyrene beads via standard commercial techniques.
• Example 2 The following immunometric assay protocol was employed for assaying IgE: Assay Method 2 (Room Temperature Plus Room Temperature 30 Minutes)
• OPD o-phenylenediamine
• Example 3 The immunometric assay protocol of Example 2 was employed with one modification. The sole modification was in step 5 in that the incubation period was increased to 150 minutes.
• the results of these assays are also set forth in Table I.
• the data set forth in Table I indicates that an assay employing monoclonal antibodies as both the labeled antibody and the bound antibody is unable to produce a detectable signal even after a long incubation period of 150 minutes.
• the data in Table I shows that in an assay employing a monoclonal antibody and a polyclonal antibody one is able to obtain excellent results after a short incubation period of only 30 minutes.

Landscapes

• Health & Medical Sciences (AREA)
• Immunology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Hematology (AREA)
• Urology & Nephrology (AREA)
• Biomedical Technology (AREA)
• Molecular Biology (AREA)
• Microbiology (AREA)
• Analytical Chemistry (AREA)
• Biotechnology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Food Science & Technology (AREA)
• Medicinal Chemistry (AREA)
• Physics & Mathematics (AREA)
• Cell Biology (AREA)
• Biochemistry (AREA)
• General Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
• Pathology (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)
• Peptides Or Proteins (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=22175382

Family Applications (1)

Country Status (2)

Families Citing this family (24)

Family Cites Families (6)

• 1983
  • 1983-07-25 WO PCT/US1983/001147 patent/WO1985000663A1/en unknown
  • 1983-07-25 EP EP19830902620 patent/EP0149602A1/de not_active Withdrawn

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events