WO2014194780A1 - 免洗涤锚定延伸端粒亲和扩增检测端粒酶的方法及试剂盒 - Google Patents

免洗涤锚定延伸端粒亲和扩增检测端粒酶的方法及试剂盒 Download PDF

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WO2014194780A1
WO2014194780A1 PCT/CN2014/078540 CN2014078540W WO2014194780A1 WO 2014194780 A1 WO2014194780 A1 WO 2014194780A1 CN 2014078540 W CN2014078540 W CN 2014078540W WO 2014194780 A1 WO2014194780 A1 WO 2014194780A1
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pcr
telomerase
primer
mmol
probe
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陈燃
金晓铮
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浙江今复康生物科技有限公司
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Priority to US14/961,251 priority Critical patent/US10161005B2/en

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Definitions

  • the invention relates to a method and a kit for washing-free, anchored-extension and Telomeric-binding Amplification (WATA) telomerase.
  • WATA Telomeric-binding Amplification
  • Telomerase is a special reverse transcriptase, a ribonucleoprotein (RP) complex composed of RA and protein, containing three major components: telomerase RNA (TERC) template, telomerase catalysis Subunit (TERT) and telomerase-associated protein (TLP).
  • TERC is a template for elongation reaction of telomerase, which is about 450 bases, including the template sequence of 5'-CUAACCCUAAC-3'
  • TERT is the protein catalytic subunit of telomerase
  • TLP is the regulatory unit of telomerase.
  • telomere-TTAGGG-repeat G sequence
  • telomere-TTAGGG-repeat G sequence
  • tissue cells such as: germ cells, embryonic cells, hematopoietic stem cells, peripheral blood lymphocytes, hair, skin, endometrium, etc.
  • telomerase activity in normal mature somatic cells, and cells cause aging and death due to the gradual shortening of telomeres.
  • telomerase reactivation is The transformation of somatic cells into tumor cells. It has been found that the vast majority of malignant cells are telomerase-positive (>85%), while the telomerase positive rate in adjacent tissues and normal tissues is very low ( ⁇ 5%). Therefore, telomerase is A widely accepted and highly specific tumor marker. Detection of telomerase is expected to develop into a powerful tool for the detection and molecular diagnosis of cancer.
  • the source of telomerase detection may be cultured cells, surgically removed tissue, needle biopsy tissue, pleural effusion, ascites, bladder or pancreatic duct irrigation, secretions from cotton swabs, sputum, urine, and the like.
  • Non-PCR type detection methods use isotope, fluorescence, and chemical luminescence to directly analyze the telomerase extension reaction product. Due to the limited sensitivity, it has been largely replaced by PCR-based assays. 2.
  • Traditional telomerase activity PCR detection method Telomeric Repeats Amplification Protocol (TRAP) and derivative methods, the amplification products are a series of DNA fragments of different lengths; 3.
  • TRIP Telomeric Repeats Amplification Protocol
  • Non-TRAP PCR detection methods including Premature Termination of telomeric Extension-Pcr (PTEP) and Anchored-Extension and Telomeric Complements Amplification (AETCA), amplification products It is a fixed-length specific DNA fragment; the traditional TRAP method requires cumbersome polyacrylamide gel electrophoresis and staining steps. Since then, although many scholars have made improvements, especially the introduction of internal standards allows for more accurate semi-quantitative determination with some analytical instruments, but these improvements are only after the detection of PCR, the TRAP-PCR core reaction It is the same, so it cannot improve the following inherent defects of the TRAP method:
  • the amplification efficiency is low. Since the TRAP method is a template for PCR directly using the product of the elongation reaction of telomerase, the obtained PCR product is a series of bands ranging from several tens of bp to several hundred bp, and the uncertainty of the amplification product is caused. Amplification efficiency is greatly limited, thus reducing sensitivity;
  • the cell lysate can be used to add to the volume of the detection reaction system, generally not exceeding 4% of the total volume, which limits the sensitivity of the assay;
  • telomerase inhibitors have a strong inhibitory effect on PCR
  • the PTEP method was reported by Chen Hua and others in 2003, and the Chinese invention patent was granted in the same year (ZL00127583.6).
  • the principle of the method is:
  • the validity of the PCR primer is the complementary binding of the 3' end to the template, and the partial mismatch in the middle of the chain does not hinder the PCR
  • the guidance of the reaction introduces a specially constructed 159 bp DNA, and the telomerase primer TS is completely complementary to the two ends of the 159 bp DNA except for the 2 base of the 3'end; the telomerase extension reaction is terminated by not adding dTTP.
  • the pre-terminated extension product TS+AGGG was obtained, after which dTTP and Taq enzymes were added to the system, and TS+AGGG was used as the starting primer to guide the amplification of the 159 bp DNA after 2 PCR cycles,
  • the fully complementary sequence of TS is synthesized into a new product, and TS is used as a PCR primer to amplify the new product.
  • the amplified product is a specific fragment of 159 bp DNA and is suitable for various conventional analytical methods.
  • the main improvement of the TRAP method is to change the indeterminate amplification product of the TRAP method to a specific amplified fragment, but because it is also the coupling of telomerase extension reaction and PCR, it cannot be excluded. Cell lysates have improved inhibition of PCR, and therefore, reproducibility/stability is not good enough. In addition, it is also cumbersome to replenish the reagents (dTTP and Taq enzymes) one by one in the middle of the reaction.
  • the AETCA method was invented in 2012 by Chen Burn et al.
  • the method utilizes a telomerase primer for telomere G sequence extension, and another template probe with a universal PCR primer sequence and 6 units of telomere C complementary sequence hybridizes to the telomere G sequence.
  • the unbound template probe is removed by repeated washing, and the template probe bound to the labeled telomere G sequence is amplified in a subsequent PCR reaction, and the product is a fixed length specific DNA fragment.
  • the repeated washing step of the method can remove the PCR inhibitory substance, and the template probe is bound to the telomere G sequence in multiple copies, and the template of the PCR is enriched, thereby improving the overall sensitivity of the method, but repeated washing.
  • the steps are relatively cumbersome.
  • the temperature control of the template probe combined with the target G sequence is relatively high, and it is affected by the change of the ambient temperature. If the room temperature is too low, it will easily lead to non-specific binding, resulting in false positives. Inconsistent factors of instability.
  • the present invention provides a significant innovation in the AETCA method: The introduction of a suppression probe-mediated digestion reaction to remove the template probe without the G-binding sequence eliminates the washing step.
  • the object of the present invention is to provide a telomerase amplification method and a detection kit which are simple, rapid, and high-performance.
  • a method for avoiding the extension of telomere affinity amplification of telomerase by washing the cells wherein the cell lysate supernatant of the sample to be tested is added to a PCR reaction tube immobilized with telomerase primer, and placed on ice The telomerase is bound to the primer, and after drying the supernatant, a telomerase reaction system consisting of a template probe, a suppression probe, a buffer and dNTP is added, and the telomere G sequence extension reaction is carried out at 30 to 37 ° C for incubation.
  • the hybridization reaction was carried out at 55 to 65 ° C, followed by blotting, and a PCR reaction solution containing a restriction enzyme and a PCR primer was added, and the mixture was incubated at 37 ° C for 10 minutes, followed by PCR reaction, and the PCR reaction product was used for Fluorescence quantification or agarose gel electrophoresis analysis;
  • telomerase primer sequence is as follows:
  • the underlined part is a sequence complementary to the template region of telomerase TERC, and its 5' end is fixed on the PCR tube wall, magnetic beads or other solid medium combined with adsorption; telomere
  • the immobilization of the enzyme primer S can be carried out by a conventional method in the art, and the solid medium for the telomerase primer S can be a plastic centrifuge tube, a magnetic bead, a gel particle or other solid medium capable of adsorbing and binding nucleic acid.
  • the template probe sequence is as follows (the two ends are PCR primer sites, and the middle is the complement of the n-unit telomeric repeat (TTAGGG) n (G sequence) (C sequence), in the C sequence and PCR A restriction enzyme restriction enzyme site is added between the epitopes):
  • the inhibitory probe sequence is as follows:
  • PCR primer sequences are as follows:
  • the method is as follows:
  • the method for preparing a cloning PCR tube immobilized with telomerase primer is as follows: TBST buffer 50 ul, containing 5 pmol biotinylated telomerase primer, and loaded with streptavidin coated 0.2 ml PCR thin-wall tube, lhr at room temperature, absorb the liquid in the tube, add 100 ⁇ l of TBST buffer, mix well, blot dry, wash repeatedly for 3 times, and finally blot dry; add lOOul TE buffer, then, drain the liquid in the tube, After sealing, place at -20 ° C for use.
  • the specific method can be as follows: The template probe and the inhibition probe are respectively dissolved in the TE buffer, and the equimolar template probe and the inhibition probe are mixed together, 60 ° C lOmin, 37 ° C lOmin, cooled to room temperature, dsTU. Since dsTU has a complete BamHI site, it can be cut by BamHI.
  • the above steps can be prepared in batches before telomerase activity assay, and stored at -20 °C for later use.
  • samples to be tested may be from tissues or cells, or clinical specimens such as sputum , blood, etc.;
  • the method for obtaining the lysate supernatant is as follows: l ⁇ 5 ml sputum + 5 ⁇ 10 ml pretreatment solution, shake at 37 °C for 10 min, centrifuge at 10 °C, 5000 rpm for 10 min, discard the supernatant, Take the precipitate + 200 ul of lysate, repeatedly pipette, transfer to a 1.5 ml centrifuge tube, place on ice for 20 min, centrifuge at 4 ° C, 15000 rpm for 20 min, and take the supernatant to obtain the lysate supernatant.
  • the composition of the pretreatment solution is: PBS + 0.1% (w/vol) DTT.
  • the lysate supernatant is obtained as follows: 24 well plate cell culture, aspirate the culture solution, add 200 ul of lysate, repeatedly pipette, transfer to a 1.5 ml centrifuge tube, and place on ice for 10 min, 4°. C, centrifugation at 15000 rpm for 20 min, the supernatant was taken to obtain a lysate supernatant;
  • the method for obtaining the lysate supernatant is as follows: Take a tissue block of about 0.1 cm 3 into a 1.5 ml centrifuge tube, add 200 ul of lysate, repeatedly pipette, transfer to a 1.5 ml centrifuge tube, and ice. Place lOmin on it, centrifuge at 20 °C at 4 ° C, 15000 rpm, and take the supernatant to obtain the lysate supernatant;
  • the lysate has the following composition: lmmol L MgCl 2 , 1 mmol L EGTA-Na, 1% (vol/vol) NP-40 (NP-40 is a very mild surfactant, and the 1% concentration can be substantially destroyed Dropped cell membrane, weak effect on nuclear membrane damage), 0.25mmol sodium deoxycholate, 150mmol/L NaCl, 10% (vol/vol) glycerol, 5mmol L 2-mercaptoethanol, O. lmmol L AEBSF, solvent It was 10 mmol L, pH 7.5 Tris-HCl.
  • telomerase reaction solution prepared by buffer (telomerase reaction buffer), dNTP and dsTU, 30 ⁇ 37 °C for 30 ⁇ 60min (in order to carry out extension reaction of telomere G sequence) ), 55-65 °C 15 ⁇ 30min (the purpose is to melt the dsTU, while recovering the single-stranded template probe T renaturation to the extended telomere G sequence.
  • the dry step can be Remove the substance that inhibits the restriction enzyme digestion and PCR reaction, and add the RE/PCR reaction solution prepared by buffer (RE PCR reaction buffer), dNTP, Taq enzyme, PCR primer, SYBR green I or TaqMan probe and BamHI.
  • the following procedure was performed on the PCR machine: digestion at 37 °C 5 ⁇ 15 mm (residual traces of dsTU were cleaved, and template probe T bound to the telomere G sequence was destroyed due to the integrity of the BamHI site, so Will be digested.
  • the integrated digestion reaction not only prevents the hybridization of the telomere extension sequence.
  • the interference of template probe B on the PCR reaction can also prevent the cross-contamination caused by the diffusion of trace amounts of PCR products, thus ensuring the specificity and success rate of the PCR reaction.
  • the buffer is a buffer commonly used for PCR reactions
  • blank lysate should be used as a negative control, and processed and analyzed according to steps (4)-(5).
  • the sample ct value is smaller than the blank lysate ⁇ value, and the absolute value of the difference is greater than or equal to 1, which is judged as Positive.
  • the telomerase reaction solution (telomerase reaction buffer + 0.06 mmol L dNTP + lnmol L dsTU) in the step (5) has the following composition: 0.06 mmol L dNTP, lnmol/L dsTU, 1.5 mmol L MgCl 2 , 63mmol/L KC1, lmmol/L EGTA-Na, O.
  • the RE PCR reaction solution (RE PCR buffer + dNTP + Taq enzyme + PCR primer + SYBR green K or TaqMan probe BamHI) in the step (5) is composed as follows: 0.2 mmol L dNTP, lU/50 ul Taq enzyme , PCR bow I substance 0.2umol / L 0.4xSYBR Green I 2U / 50ul BamHI, 50mmol / L KC1, 1.5mmol L MgCl 2 0.05% (vol / vol) Tween20, solvent is 10mmol L pH9.0 Tris-HCl
  • the invention also relates to a kit for washing-free extended telomere affinity amplification detection of telomerase activity, mainly comprising a PCR tube, template probe, inhibition probe, PCR primer immobilized with telomerase primer , telomerase reaction buffer, RE PCR reaction buffer, and Taq enzyme and BamHI enzyme; the above are the main reagents of the kit, and also dNTP SYBR Green I or TaqMan probe, etc., and those skilled in the art can select according to needs. ;
  • telomerase primer sequence is as follows:
  • the template probe sequence is as follows:
  • the inhibitory probe sequence is as follows:
  • PCR primer sequences are as follows:
  • the telomerase reaction buffer has the following composition: 1.5 mmol/L MgCl 2 63 mmol/L KC1, 1 mmol L EGTA-Na, O.lmg/ml BSA, 0.05% Tween 20, solvent 20 mmol L pH 8.0 Tris-HCl
  • the composition of the RE PCR reaction buffer is as follows: 50 mmol L KCl 1.5 mmol L MgCl 2 0.05% Tween 20, the solvent is 10 mmol L Tris-HCl pH 9.0
  • the kit may further comprise a cell lysate having the following composition: lmmol/L MgCl 2 lmmol/L EGTA-Na, 1% ⁇ -40, 0.25 mmol/L sodium deoxycholate, 150 mmol L NaCl 10% (vol/ Vol) glycerol, 5 mmol/L 2-mercaptoethanol, 0. lmmol/L AEBSF, solvent 10 mmol/L pH 7.5 Tris-HCl »
  • a cell lysate having the following composition: lmmol/L MgCl 2 lmmol/L EGTA-Na, 1% ⁇ -40, 0.25 mmol/L sodium deoxycholate, 150 mmol L NaCl 10% (vol/ Vol) glycerol, 5 mmol/L 2-mercaptoethanol, 0. lmmol/L AEBSF, solvent 10 mmol/L pH 7.5 Tris-HCl »
  • the TRAP method is to amplify the telomere extension product, and the present invention retains the advantage of the AETCA method, that is, the telomere extension sequence is not used as a PCR template, but a template probe complementary to the telomere sequence is used as a PCR template.
  • the template probe can bind to the longer telomere extension sequence synthesized by telomerase in multiple copies, so that although the length of the telomere extension sequence is not fixed, the amplification of the template probe can maintain an efficient fixed length.
  • the inefficient defects of the TRAP method whose amplification length is not fixed are overcome.
  • the method does not need to carry out the repeated washing step of the AETCA method, thereby simplifying the operation and enhancing the consistency, and the method firstly binds the telomerase molecule to the telomerase primer by low temperature adsorption, and removes by absorbing the dry liquid. PCR inhibitors increase PCR amplification efficiency.
  • the method of the present invention increases the amount of template used for PCR, thus increasing the sensitivity of detection.
  • the estimated amount of improvement for the template is as follows:
  • the amount of template probe that can be bound by the telomere extension product is estimated by increasing the telomere extension product in increments of 6 bp from 36 bp (6 units) to 354 bp (59 units).
  • telomere extension products a total of 6 6bp increasing telomere extension products, which can be combined with one template probe;
  • 72bp ⁇ 102bp a total of 6 6bp increasing telomere extension products, which can be combined with two template probes;
  • 324bp ⁇ 354bp A total of 6 6bp increasing telomere extension products, which can bind 9 template probes respectively; b.
  • the total bound template probe amount is:
  • the sensitivity of the method can be estimated to be 270 times that of the TRAP method.
  • Another important advantage of the method of the present invention is that it can limit the false positive cross-contamination caused by the amplification products to some extent.
  • the beneficial effects of the invention are mainly embodied in: the method of the invention is simple and convenient to operate, can improve the sensitivity and specificity of the detection of telomerase activity, and is suitable for detecting cells or tissues of various sources including clinical samples derived from sputum and the like. .
  • FIG. 1 is a schematic flow chart of a method of the present invention
  • Step S0 immobilized telomerase primer (TS);
  • Step Sl lysing the cells to obtain a lysate supernatant containing telomerase molecules
  • Step S2 placing on ice, causing adsorption of telomerase molecules to the TS;
  • Step S4 after blotting, adding RE PCR system, adding 37 ° C incubation before PCR reaction procedure to cleave excess template probe, template probe bound to telomere extension product, because the enzyme cleavage site is single-stranded Can not be cut and remain intact;
  • Step S5 continue the PCR procedure, the template probe is amplified, and the results show telomerase activity;
  • TS telomerase primer
  • TPB template probe
  • CSC inhibitory probe
  • RS cleavage site
  • Example 1 Wam system integrated with BamHI can remove trace interference of dsTU to PCR
  • telomerase primer S The sequence of telomerase primer S is as follows: 5 7 -TCCGTCGAGCAGAGTTAGGGTTAG-3 ';
  • the inhibitory probe U sequence is as follows: 5 '- TAGGGTTAGGGATCCTACA -3 ';
  • PCR primer sequences are as follows:
  • Lysate T composition lmmol/L MgCl 2 , 1mmol L EGTA-Na, 1% (vol/vol) NP-40, 0.25mmol L sodium deoxycholate, 150mmol L NaCl, 10% (vol/vol) glycerol, 5mmol L 2-mercaptoethanol, 0. lmmol L AEBSF, solvent 10 mmol L, pH 7.5 Tris-HCL
  • the telomerase reaction solution (reaction solution T) has the following composition: 0.06 mmol L dNTP, lnmol L dsTU, 1.5 mmol L MgCl 2 , 63 mmol/L KCl, 1 mmol/L EGTA-Na, O.lmg/ml BSA, 0.05% Tween20
  • the solvent was 20 mmol L, pH 8.0 Tris-HCl.
  • composition of the RE PCR reaction solution was as follows: 0.2 mmol L dNTP, lU/50 ul Taq enzyme, PCR primer 0.2 umol L, 0.4 x SYBR Green I, 2 U/50 ul BamHI, 50 mmol L KCl, 1.5 mmol L MgCl 2 , 0.05% Tween 20, solvent 10 mmol L, pH 9.0 Tris-HCl.
  • Composition of conventional PCR reaction solution without BamHI 0.2mmol L dNTP, lU/50ul Taq enzyme, PCR primer 0.2umol/L, 0.4xSYBR Green I, 50mmol L KCl, 1.5mmol/L MgCl 2 , 0.05% Tween20, solvent 10 mmol L, pH 9.0 Tris-HCl.
  • Human lung cancer cell line A549 cells (purchased from ATCC, USA) were cultured in a 24-well plate at 10,000 cells/well for a total of 8 well cells. After overnight culture, the culture solution was aspirated, 200 ul/well lysate T was added, and the cells were repeatedly aspirated and transferred to 8 1.5 ml centrifuge tubes, placed on ice for 10 min, centrifuged at 4 ° C, 15000 rpm for 10 min, and the supernatant was taken. The supernatant was lysed.
  • RE PCR 29.05 29.42 It can be seen that the Ct values of the two systems dd3 ⁇ 40 control (derived from the primer dimer) >29. Conventional PCR, dsTU tube Ct value ⁇ 21, far less than the control, indicating that the reaction tube containing lnmol L dsTU lysis supernatant after the blotting, the residual trace dsTU has obvious amplification.
  • Example 2 Wam system integrated with BamHI can remove the interference of trace PCR product contamination
  • the primer, the probe sequence, the reaction tube, the lysate T, the reaction solution, the conventional PCR reaction solution, and the RE PCR reaction solution were as in Example 1.
  • the preparation of A549 cells and lysate supernatant was the same as in Example 1. Fixed were taken 50ul lysis supernatant was added to 0.2ml of eight reaction tubes have telomerase primers, which were then added 4 dilution of the amplification product 10-7, four additional equal volume of dd3 ⁇ 40 Control, incubate at 30 °C for 30 min, then incubate at 60 °C for 30 min, blot dry, 4 tubes (2 containing amplification products, 2 ddH 2 0 controls, the same below) to add conventional PCR system without BamHI, another 3 tubes
  • the RE PCR system containing BamHI was added to the SYBR green l fluorescence quantitative analysis on a real-time PCR machine at 37 ° C lOmin, 94 ° C for 3 min, and then 40 cycles of 94 ° C 5 sec 63 ° C for 30 sec. The results are as follows:
  • RE PCR 29.03 29.50 seen, two kinds of systems ddH 2 0 Ct control value (derived from primer dimers)> 29.
  • Conventional PCR the amplification product tube 03 ⁇ 4 value ⁇ 16, is far less than the control, indicating dilution of the amplification product 10-7 false positive can result in serious pollution to the conventional PCR system, and the RE / PCR amplification product value tube 03 ⁇ 4 >29, comparable to the control, indicating that the RE PCR system can effectively cut false positives caused by contamination of trace amounts of amplification products.
  • Example 3 Detection of telomerase activity in human lung cancer A549 cells by WATA assay
  • the detection method is as follows:
  • A549 cells were cultured in 24-well plates (about 10-10,000 cells/well), and the culture solution was aspirated. Add 200 ⁇ l/well of lysate T, repeatedly pipet, transfer to a 1.5 ml centrifuge tube, and place on ice. After centrifugation at 20 ° C, 1 ° C for 20 min at 20 ° C, the supernatant was taken to obtain a lysate supernatant.
  • reaction tubes which are divided into 6 groups, 4 groups/groups. After sealing, they are placed at 37 °C for 1, 2, 3, 4, 5, and 6 days, and are recorded as group 1, group 2, group 3, Group 4, Group 5, Group 6.
  • Example 2 2) Prepare the A549 cell lysis supernatant as in Example 1 for a total of 2 x 1 ml, 1 ml of which was placed on ice for use as a positive control; and another 1 ml of heat inactivated treatment (80 ° C 10 mm) as Negative control.
  • the detection method is as follows:
  • A431 cells were cultured in 24-well plates (about 10-10,000 cells/well), and the culture solution was aspirated. 200 ul/well of lysate T was added, repeatedly pipetted, transferred to a 1.5 ml centrifuge tube, and placed on ice for 20 min. After centrifugation at 15,000 rpm for 20 min at 4 ° C, the supernatant was taken to obtain a lysate supernatant.
  • the following operation was the same as in Example 3, with a value of 03 ⁇ 4 ⁇ 28, which was judged as positive, and a value of 03 ⁇ 4 > 28, which was judged to be negative.
  • the kit for 8 people consists of the following:
  • Pretreatment liquid concentrate sample pretreatment, collecting, enriching, washing cells, etc. IX 1.7ml
  • Pretreatment liquid concentrate composition 50xPBS + 50g L DTT, diluted 50 times, it is lxPBS + lg L DTT; lxPBS composition is as follows: NaC1 137mM, KC1 2.7mM, Na 2 HP0 4 10mM, KH 2 P0 4 1.8mM, solvent For distilled water;
  • Collect samples which may be cultured cells, tissues, sputum, whole blood (plus anticoagulant), urine samples, etc.
  • Samples Recommended dosage culturing the cells of about 10 to 106, about the size of tissue O.lcm 3, sputum about 2ml, whole blood about 0.5ml, about urine 10ml.
  • Sample pretreatment method Suspension cultured cells, collected by centrifugation, resuspended in 10 ml of pretreatment solution; tissue block was immersed in 10 ml of pretreatment solution, and chopped; sputum was added with 10 ml of pretreatment solution, and shaken at 37 ° C for about 10 mm. The sputum is completely dissolved; the whole blood is directly added with 10 ml of the pretreatment solution; after the urine sample is centrifuged, the pellet is resuspended in 10 ml of the pretreatment solution; the above supernatants are again centrifuged, and the precipitate is transferred to the next step.
  • Control setting Replace the lysate supernatant with the negative control and the positive control, and perform the above steps 5) to 6).
  • 293T cells (cells purchased from ATCC, USA) were cultured in 24-well plates (about 1-10 6 cells/well). See Example 5 for the kit and procedure.
  • the heat inactivation treatment of 1000 cell lysis supernatants was the same as in Example 3.
  • the WATA kit can detect telomerase activity in 10-10 6 293T cells, but when the number of sample cells reaches or exceeds 10 5 , the Ct value is no longer significantly reduced, indicating that the amplification limiting factor has been The granule G sequence extends to the template probe, ie all template probes have been bound to adsorb, thus, although higher telomerase activity results in more telomere G sequence extension, it does not continue to result in PCR template amount Increase.
  • Example 7 Detection of telomerase activity of human cervical cancer cell line Hela cells by WATA telomerase activity assay kit
  • Hela cells (cells purchased from ATCC) using 24-well plates for cell culture (about 10-105 cells / well). See Example 5 for the kit and procedure. The heat inactivation treatment of 1000 cell lysis supernatants was the same as in Example 3.
  • Example 8 Detection of telomerase activity of human breast cancer cell line MCF-7 by WATA telomerase activity assay kit
  • MCF-7 cells purchased from Cell ATCC using 24-well plates for cell culture (about 10 to 10 5 / well). See Example 5 for the kit and procedure.
  • the heat inactivation treatment of 1000 cell lysis supernatants was the same as in Example 3.
  • telomerase activity assay kit can detect telomerase activity in 10-10 6 MCF-7 cells, and within this range, the number of cells, the lower the Ct value, suggesting that the detection of WATA telomerase activity is useful. The value of quantitative testing.
  • Example 9 Detection of telomerase activity in sputum samples from lung cancer patients by WATA telomerase activity assay kit
  • the WATA method can detect telomerase activity from fresh sputum of most lung cancer patients.
  • Example 10 Detection of cervical cancer surgically resected tissue using WATA telomerase activity assay kit
  • Surgical resection of 10 patients with cervical cancer was frozen at -80 °C. Take about 30 mg of frozen cervical tissue, cut with sterile ophthalmic scissors, force 10 ml of pretreatment solution, centrifuge, discard the supernatant, add 200ul of lysate T, ice bath 30 mm, the following operation according to the procedure of Example 5 get on.
  • the kit is the same as in Example 5.
  • telomere extension replacement mechanism is a mechanism by which telomerase-negative cancer cells extend and maintain telomere DNA length.
  • SK-LU-1 (cell purchased from ATCC, USA) is a known ALT+ cell cultured in a 24-well plate (about 10-10 5 cells/well). See Example 5 for the kit and procedure. The heat inactivation treatment of 1000 SK-LU-1 cell lysis supernatants was the same as in Example 3.
  • TAACCCTAACCCTAACCCTAACCCTAACCCTAACCC-TAMRA-3 ' Replaces SYBR green I.
  • the cells are A549 cells.
  • the detection method was the same as that in Example 3, and the SYBR green I analysis was replaced by FAM fluorescence quantitative analysis, and the value was judged to be positive by 0 value ⁇ 30, and the value was judged to be negative by 0 value > 30 or no Ct;
  • telomerase activity can be detected in 10-10000 A549 cells using TaqMan's WATA method.

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Abstract

本发明提供了一种新的端粒酶扩增方法——免洗涤的锚定延伸端粒亲和扩增(Washing-free, Anchored-extension and Telomeric-binding Amplification:WATA)。该方法利用一个锚定端粒酶引物进行端粒TTAGGGG序列(简称为G序列)延伸,以另一带有通用PCR引物序列和6个单元的端粒CCCTAA序列(简称为C序列)的模板探针杂交结合在延伸的G序列上,通过酶切反应,除去未结合的模板探针,与G序列结合的模板探针进行PCR反应,扩增产物为一个固定长度的特异DNA片段。

Description

免洗涤铺定延伸端粒亲和扩增检测端粒酶的方法及试剂盒
(一) 技术领域
本发明涉及一种免洗涤铺定延伸端粒亲和扩增 (Washing-free, Anchored-extension and Telomeric-binding Amplification; WATA) 端粒酶的方法及试剂盒。
(二) 背景技术
端粒酶(telomerase)是一种特殊的逆转录酶, 是由 R A和蛋白质组成的核糖核蛋白 (R P) 复合物, 包含 3个主要成分: 端粒酶 RNA (TERC)模板, 端粒酶催化亚单位(TERT)和端粒酶 相关蛋白 (TLP )。 TERC 是端粒酶进行延伸反应的模板, 约有 450 个碱基, 其中包含 5'-CUAACCCUAAC-3'的模板序列, TERT是端粒酶的蛋白催化亚基, TLP是端粒酶的调节单位。 端粒酶的主要功能是利用染色体末端端粒 DNA的 3'末端为引物, 以自身 RNA为模板合成延伸端 粒 -TTAGGG-重复序列 (G序列), 从而弥补细胞分裂过程中丢失的端粒 DNA序列。 在一些特定 的组织细胞, 如: 生殖细胞、 胚胎细胞、 造血干细胞、 外周血淋巴细胞、 毛发、 皮肤、 子宫内膜 等分裂旺盛的组织细胞中有低水平的活化端粒酶的表达, 但在正常成熟的体细胞中则没有端粒酶 活性, 细胞因为端粒的逐渐缩短而导致衰老和死亡。 极少数体细胞可能偶然通过激活端粒酶而逃 逸程序性老化, 其生存延长可能给另外的基因损伤的积累提供机会, 导致进行性肿瘤性发展, 即 癌变, 因此, 端粒酶的重新激活是体细胞向肿瘤细胞转化, 即癌变的关键步骤。 目前发现, 绝大 多数的恶性肿瘤细胞都呈端粒酶阳性 (>85%), 而在癌旁组织和正常组织的端粒酶阳性率很低 (<5%), 因此, 端粒酶是一个被广泛接受的特异性很高的肿瘤标志物。端粒酶的检测有望发展成 为对癌症进行检测和分子诊断的有力手段。 端粒酶检测的标本来源可以是培养细胞、 手术摘除组 织、 针吸活检组织、 胸水、 腹水、 膀胱或胰管冲洗液、 棉拭子所取分泌物、 痰液、 尿液等。
现有端粒酶活性检测方法有三类: 1. 非 PCR类的检测方法。 这些方法采用同位素, 荧光, 化 学发光等对端粒酶延伸反应产物进行直接分析测定。 由于灵敏度有局限, 目前已经基本被基于 PCR 扩增的检测方法所取代。 2.传统的端粒酶活性 PCR检测方法: 端粒重复序列扩增方法 (Telomeric Repeats Amplification Protocol, TRAP) 及衍生方法, 扩增产物是一系列长度不等的 DNA 片段; 3.非 TRAP类的 PCR检测方法, 包括提前中止端粒序列延伸 - PCR (Premature Termination of telomeric Extension-Pcr, PTEP )和铺定延伸端粒序列亲和扩增 (Anchored-Extension and Telomeric Complements Amplification, AETCA), 扩增产物是一个固定长度的特异 DNA片段; 传统的 TRAP法需要进行繁琐的聚丙烯酰胺凝胶电泳及染色步骤。 此后, 虽然许多学者又 进行了改进, 尤其是内标的引入使得借助某些分析仪器可以进行较精确的半定量测定, 但这些改 进只是在 PCR后的检测手段上的, 采用的 TRAP-PCR核心反应是相同, 因而无法改善 TRAP法 的如下固有缺陷:
( 1 ) 扩增效率低。 因为 TRAP法是直接以端粒酶的延伸反应的产物做 PCR的模板, 得到的 PCR产物是从几十 bp到几百 bp的大小不等的一系列条带, 扩增产物的不确定性导致扩增效率受 到了很大限制, 因而降低了灵敏度;
(2 ) 特异性的问题。 TRAP 扩增产物的不确定性所衍生的问题是结果分析容易收到非特异 PCR扩增的干扰;
(3 )可重复性 /稳定性不好。 因为 TRAP法是直接将细胞裂解液加入到 PCR体系中的, 而细 胞裂解液往往含有很多抑制 PCR反应的成分, 所以很容易导致整个检测的失败;
(4)体系对灵敏度的限制。细胞裂解液可用来加入到检测反应体系中的体积, 一般不能超过 总体积的 4%, 这就限制了检测的灵敏度;
(5 ) 适用性有局限, 不适合用于检测端粒酶抑制的效果。 因为 PCR与端粒酶延伸反应是偶 联在一起的, 而端粒酶抑制剂对 PCR有很强的抑制作用;
(6) 难于结合实施荧光实时定量 PCR。 非特异 PCR扩增的干扰导致, 不适合用 SYBR染料 法, 而探针区域与下游引物区域重叠, 不适合用 TaqMan探针法。
PTEP法由陈燃等人于 2003年报道, 同年获得中国发明专利授权 (ZL00127583.6)。 该方法 的原理是: PCR引物的有效性是其 3'端与模板的互补结合, 而链中间的部分错配不阻碍对 PCR 反应的引导。该方法引入一段专门构建的 159bp DNA,端粒酶引物 TS除了 3 '末端的 2个碱基外, 与该 159bp DNA的两端完全互补; 通过不加入 dTTP, 将端粒酶延伸反应限定终止在一个单元之 内, 得到提前终止的延伸产物 TS+AGGG, 之后, 向体系中加入 dTTP和 Taq酶, TS+AGGG做 为起始引物引导对该 159bp DNA进行扩增 在 2个 PCR循环之后,由于 TS的完全互补序列被合 成到新的产物中, TS被用作 PCR引物对新的产物进行扩增。扩增产物为 159bp DNA的特异片段, 适合于各种常规分析方法。 该方法对 TRAP法的主要改进是将 TRAP法的大小不等的不确定的扩 增产物改变为一个特异的扩增片段, 但因为也是端粒酶延伸反应与 PCR的偶联, 未能在排除细 胞裂解液对 PCR的抑制方面有所改进, 因此, 可重复性 /稳定性等方面不够好。 另外, 需要在反 应中间, 逐管补充试剂 (dTTP和 Taq酶), 也比较繁琐。
AETCA法由陈燃等人于 2012年发明。该方法利用一个铺定端粒酶引物进行端粒 G序列延伸, 以另一个带有通用 PCR引物序列和 6个单元的端粒 C互补序列的模板探针杂交结合在铺定的端 粒 G序列上, 通过反复洗涤, 除去未结合的模板探针, 与铺定的端粒 G序列结合的模板探针则在 随后的 PCR反应被扩增, 产物为一个固定长度的特异 DNA片段。 该方法采用的反复洗涤步骤可 以除去 PCR抑制物质, 并且模板探针以多拷贝的形式结合在铺定的端粒 G序列上, 富集了 PCR 的模板, 提高了方法的整体灵敏度, 但反复洗涤步骤比较比较繁琐, 模板探针与目标 G序列结合 的温度控制要求较高, 且受环境温度变化的影响, 若室温过低, 则容易导致非特异的结合, 造成 假阳性, 这些给结果造成了不稳定不一致的因素。 本发明对 AETCA法进行了重大的革新改进: 通过引入一个抑制探针介导的酶切反应除去未结合 G序列的模板探针, 免去了洗涤步骤。
(三) 发明内容
本发明目的是提供一种操作简单快速、 高性能的端粒酶扩增方法及检测试剂盒。
本发明采用的技术方案是:
一种免洗涤铺定延伸端粒亲和扩增端粒酶的方法, 所述方法是将待测样品的细胞裂解上清液 加入固定有端粒酶引物的 PCR反应管中, 冰上放置使端粒酶与引物结合, 吸干上清后, 加入由模 板探针、 抑制探针、 缓冲液和 dNTP组成的端粒酶反应体系, 在 30~37°C保温进行端粒 G序列延 伸反应,随即在 55~65 °C保温进行杂交反应,之后吸干,加入含有限制性内切酶和 PCR引物的 PCR 反应液, 先以 37°C保温 10分钟, 随即进行 PCR反应, PCR反应产物用于荧光定量或琼脂糖凝胶 电泳分析;
所述端粒酶引物序列如下:
5 '-TCCGTCGAGCAGAGTTAGGGTTAG-3 '; 其下划线部分为与端粒酶 TERC的模板区域互 补结合的序列, 其 5 '端固定在 PCR管壁、磁珠或其他和吸附结合合算的固体介质上; 端粒酶引物 S的固定可以采用本领域常规方法进行, 用于端粒酶引物 S的固体介质, 可以是塑料离心管, 也 可以是磁珠, 凝胶颗粒或其他可以吸附结合核酸的固体介质。
所述模板探针序列如下 (其两端为 PCR 引物位点, 中间为 n 个单元的端粒重复序列 (TTAGGG)n ( G序列) 的互补序列 (C序列), 在 C序列与 PCR弓 I物位点之间加入有限制性内切 酶的酶切位点):
||GGATCGCTCGCGGCTCT^3 '; 阴影部分是 6个单元的 G序列 (TTAGGG)6的互补的 C序列, 下划线标出的序列是 BamHI的识别位点,方框内为与抑制序列结合的区域,两端序列分别为 PCR 通用引物对: 5 '-CCGTCACCCTGGATGCTGTAGG-3'和 5 '-AAGAGC C G C G A GCG A TCCTT-3 ' 的 PCR识别位点。
所述抑制探针序列如下:
5 '- TAGGGTTAGGGATCCTACA -3 '; 下划线标出的是 BamHI识别位点;
所述 PCR引物序列如下:
上游弓 I物: 5 ' -CCGTCACCCTGGATGCTGTAGG -3 ',
下游引物: 5'-AAGAGCCGCGAGCGATCCTT -3 Ό
具体的, 所述方法如下:
( 1 ) 合成端粒酶引物, 将其固定到 PCR反应管中, 得到铺定 PCR管; 优选的, 所述的固定有端粒酶引物的铺定 PCR管的制作方法如下: TBST缓冲液 50ul, 含有 5pmol生物素化的端粒酶引物, 装入链霉亲和素包被的 0.2ml PCR薄壁管中, 室温 lhr, 吸干管内 液体, 加 lOOul TBST缓冲液, 打匀, 吸干, 如此反复洗涤共 3次, 最后吸干; 加 lOOul TE缓冲 液, 然后, 吸干管内液体, 密封后放置于 -20°C备用。
(2 ) 分别合成模板探针和抑制探针;
( 3 ) 将模板探针和抑制探针复性结合形成双链 DNA, 记作 dsTU;
具体方法可如下: 模板探针和抑制探针分别溶解在 TE缓冲液中, 取等摩尔的模板探针和抑 制探针混合在一起, 60 °C lOmin, 37°C lOmin, 冷却到室温, 得到 dsTU。 由于 dsTU带有完整的 BamHI位点, 所以能被 BamHI切割。
以上步骤都可以在进行端粒酶活性检测之前批量准备好, 冻存于 -20°C备用。
(4 ) 取待测样本, 加入裂解液, 反复吸打, 转移至离心管中, 冰上放置 10mm, 4°C离心, 取上清液, 得到裂解上清液; 所述裂解液为本领域常规含有表面活性剂(如吐温 20、 NP-40, CHAPS等)、 用于细胞或组织裂解得到保留端粒酶活性的缓冲液; 待测样本可来自组织或细胞, 或者临床标本如痰液、 血液等;
待测样本来自痰液时, 裂解上清液获得方法如下: l~5 ml痰液 + 5~10 ml前处理液, 37°C振 荡 10min, 4°C、 5000 rpm离心 lOmin, 弃上清, 取沉淀 + 200 ul裂解液, 反复吸打,转移到 1.5 ml 离心管中, 冰上放置 20min, 4°C、 15000 rpm离心 20min, 取上清, 得到裂解上清液; 前处理液 组成为: PBS+0.1% (w/vol) DTT。
待测样本来自细胞时, 裂解上清液获得方法如下: 24孔板细胞培养, 吸去培养液,加入 200ul 裂解液, 反复吸打, 转移到 1.5 ml 离心管中, 冰上放置 10min, 4°C、 15000 rpm 离心 20min, 取 上清, 得到裂解上清液;
待测样本来自组织时, 裂解上清液获得方法如下: 取约 0.1cm3大小的组织块放入 1.5 ml离 心管中,加入 200ul裂解液,反复吸打,转移到 1.5 ml离心管中,冰上放置 lOmin, 4°C、 15000 rpm 离心 20mm, 取上清, 得到裂解上清液;
优选的, 所述裂解液组成如下: lmmol L MgCl2, lmmol L EGTA-Na, 1% (vol/vol) NP-40 (NP-40 是很温和的表面活性剂, 1%浓度的基本可以破坏掉胞膜, 而对核膜破坏的作用弱), 0.25mmol L脱氧胆酸钠, 150mmol/L NaCl, 10% (vol/vol) 甘油, 5mmol L 2-巯基乙醇, O. lmmol L AEBSF, 溶剂为 10mmol L、 pH7.5 Tris-HCl。
( 5 ) 取裂解上清液至铺定 PCR管中, 轻轻振荡后, 冰上放置 30mm (目的是使得裂解上 清液中的端粒酶分子与固定的端粒酶引物结合吸附在反应管中。), 吸干,加入由缓冲 液(端粒酶反应缓冲液)、 dNTP和 dsTU配制的端粒酶反应液, 30~37°C 30~60min (目 的是进行端粒 G序列的延伸反应), 55-65 °C 15~30min (目的是解链 dsTU, 同时恢 复单链的模板探针 T复性结合到延伸的端粒 G序列上。), 吸干管内液体 (吸干的步 骤可以除去抑制干扰酶切及 PCR反应的物质),加入由缓冲液 (RE PCR反应缓冲液)、 dNTP, Taq酶、 PCR引物、 SYBR green I或 TaqMan探针及 BamHI所配制的 RE/PCR 反应液, 在 PCR仪上进行如下程序: 37°C酶切 5~15mm (残留痕量的 dsTU被切割, 与端粒 G序列结合的模板探针 T, 因 BamHI位点的完整性被破坏了, 因此不会被酶 切。 整合的酶切反应不仅能防止未与端粒延伸序列杂交结合的模板探针 B对 PCR反 应的干扰, 也能防止痕量的 PCR产物气溶胶扩散造成的交叉污染, 从而保证了 PCR 反应的特异性和成功率), 92~95 °C预变性 2~5min,然后 35个循环的 92~95 °C3~30sec, 55-65 °C 20~60sec;扩增产物用于荧光定量分析;所述缓冲液为常规用于 PCR反应的 缓冲液;
实际检测时, 需以空白裂解液作为阴性对照, 按照步骤 (4 ) - ( 5 ) 方法进行处理和分 析, 以样本 ct值小于空白裂解液 α值, 且差的绝对值大于等于 1, 判断为阳性。
优选的,步骤(5 )中所述端粒酶反应液(端粒酶反应缓冲液 +0.06mmol L dNTP+lnmol L dsTU) 组成如下: 0.06mmol L dNTP, lnmol/L dsTU, 1.5mmol L MgCl2, 63mmol/L KC1, lmmol/L EGTA-Na, O. lmg/ml BSA, 0.05% (vol/vol) Tween20, 溶剂为 20mmol L、 pH8.0 Tris-HCL 优选的, 步骤(5 ) 中所述 RE PCR反应液(RE PCR缓冲液 +dNTP+Taq酶 +PCR引物 +SYBR green K或 TaqMan探针 BamHI )组成如下: 0.2mmol L dNTP, lU/50ul Taq酶, PCR弓 I物 0.2umol/L 0.4xSYBR Green I 2U/50ul BamHI, 50mmol/L KC1, 1.5mmol L MgCl2 0.05% (vol/vol ) Tween20, 溶剂为 10mmol L pH9.0的 Tris-HCl
本发明还涉及一种免洗涤铺定延伸端粒亲和扩增检测端粒酶活性的试剂盒, 主要包括固定有 端粒酶引物的铺定 PCR管, 模板探针、 抑制探针、 PCR引物, 端粒酶反应缓冲液、 RE PCR反应 缓冲液, 以及 Taq酶和 BamHI酶;上述为试剂盒主要试剂, 还有 dNTP SYBR Green I或 TaqMan 探针等, 本领域普通技术人员可根据需要进行选择;
所述端粒酶引物序列如下:
57-TCCGTCGAGCAGAGTTAGGGTTAG-3 '
所述模板探针序列如下:
議議 GGATCGCTCGCGGCTCTT -3'
所述抑制探针序列如下:
5 '- TAGGGTTAGGGATCCTACA -3 '
所述 PCR引物序列如下:
5 '-CCGTCACCCTGGATGCTGTAGG -3',
5 '-AAGAGCCGCGAGCGATCCTT -3 '
所述端粒酶反应缓冲液组成如下: 1.5mmol/L MgCl2 63mmol/L KC1, lmmol L EGTA-Na, O.lmg/ml BSA, 0.05% Tween20, 溶剂为 20mmol L pH8.0 Tris-HCl
所述 RE PCR反应缓冲液组成如下: 50mmol L KCl 1.5mmol L MgCl2 0.05% Tween20, 溶 剂为 10mmol L pH9.0的 Tris-HCl „
所述试剂盒中还可包括细胞裂解液, 组成如下: lmmol/L MgCl2 lmmol/L EGTA-Na, 1%ΝΡ-40, 0.25mmol/L脱氧胆酸钠, 150mmol L NaCl 10% (vol/vol) 甘油, 5mmol/L 2-巯基乙 醇, 0. lmmol/L AEBSF, 溶剂为 10mmol/L pH7.5 Tris-HCl »
TRAP法是对端粒延伸产物进行扩增, 而本发明保留了 AETCA方法的优点, 即不以端粒延 伸序列为 PCR模板, 而是以与端粒序列互补结合的模板探针为 PCR模板, 该模板探针能够以多 拷贝的形式结合在端粒酶合成的较长的端粒延伸序列上, 这样虽然端粒延伸序列的长度不固定, 模板探针的扩增仍能保持高效的固定长度, 从而克服了 TRAP法的扩增长度不固定的低效缺陷。 本方法不用进行 AETCA法的反复洗涤步骤, 因此简化了操作, 增强了一致性, 并且方法上先通 过低温吸附把端粒酶分子结合到铺定的端粒酶引物上, 通过吸干换液去除 PCR抑制物, 提高了 PCR扩增效率。
与 TRAP法相比, 本发明的方法提高了用于 PCR的模板量, 因此提高了检测的灵敏度。模板 的提高量的估算如下:
以通常端粒延伸产物以 6bp的单元递增分布在从 36bp (6个单元) ~354bp (59个单元)之间 来估算, 端粒延伸产物可以结合的模板探针量为:
a. 36bp~66bp: 共 6个 6bp递增的端粒延伸产物, 分别可以结合 1个模板探针;
72bp~102bp:共 6个 6bp递增的端粒延伸产物, 分别可以结合 2个模板探针;
324bp~354bp: 共 6个 6bp递增的端粒延伸产物, 分别可以结合 9个模板探针; b. 总的被结合的模板探针量为:
(1+2+3 +4+5 +6+7+8+9) 6=270,
因此, 推算出本方法的灵敏度可以是 TRAP法的 270倍。
由于只有在存在 6个单元以上的单链 TTAGGG端粒 DNA序列的情况下,模板区域的 BamHI 位点的完整性被破坏, 而 PCR扩增产物中 BamHI位点是保持完整的, 若痕量的扩增产物污染到 WATA体系, 这些扩增产物将被体系中的 BamHI切割, 因此, 本发明方法的另一个重要优点是能 在一定程度上限制扩增产物造成的假阳性交叉污染。 本发明的有益效果主要体现在: 本发明方法操作简便易行, 可提高端粒酶活性检测的灵敏度 和特异性, 适合对各种来源的包括来源于痰液等临床标本的细胞或组织进行检测。
(四) 附图说明
图 1为本发明方法流程示意图;
步骤 S0, 固定端粒酶引物 (TS);
步骤 Sl, 裂解细胞, 得到裂解上清液, 其中含有端粒酶分子;
步骤 S2, 冰上放置, 使得端粒酶分子吸附结合到 TS上;
步骤 S3, 吸干后, 加入端粒酶反应体系, 先进行端粒延伸反应, 再进行杂交反应, 模板探针 与端粒延伸产物结合;
步骤 S4, 吸干后, 加入 RE PCR体系, PCR反应程序前增加 37°C保温以切割多余的模板探 针, 与端粒延伸产物结合的模板探针, 因为酶切位点处呈单链状态不能被切割而保持完整; 步骤 S5,继续进行 PCR程序, 模板探针被扩增, 结果显示端粒酶活性;
TS, 端粒酶引物; TPB, 模板探针; CSC, 抑制探针; RS, 酶切位点。
(五) 具体实施方式
下面结合具体实施例对本发明进行进一步描述, 但本发明的保护范围并不仅限于此: 实施例 1: 整合有 BamHI的 WATA体系, 可以除去痕量的 dsTU对 PCR的干扰
( 1 ) 合成各引物和探针序列:
端粒酶引物 S序列如下: 57-TCCGTCGAGCAGAGTTAGGGTTAG-3 ';
模板探针 T序列如下:
HT Δ TC C ΑΤΠ ΤΠΤ A ΠΓ ΑΤΓΓΓΤΑ Δ ΡΡΤΔ T Δ Δ Ρ ΤΔ Δ Ρ ΤΔ Δ ΡΡΤΔ Α Γ
GATCGCTCGCGGCTCTT -3';
抑制探针 U序列如下: 5 '- TAGGGTTAGGGATCCTACA -3 ';
PCR引物序列如下:
5 '-CCGTCACCCTGGATGCTGTAGG -3',
5 '-AAGAGCCGCGAGCGATCCTT -3 '。
(2) 固定有端粒酶引物 S的铺定 PCR管制作:
TBST缓冲液 50ul, 含有 5pmol生物素化的端粒酶引物 S, 装入链霉亲和素包被的 0.2ml PCR 薄壁管中, 室温 lhr, 吸干管内液体, 加 lOOul TBST缓冲液, 打匀, 吸干, 如此反复洗涤共 3次, 最后吸干; 加 lOOul TE缓冲液, 然后, 吸干管内液体, 密封后放置于 -20°C备用。
(3 ) 裂解液及反应液组成:
裂解液 T组成: lmmol/L MgCl2, lmmol L EGTA-Na, 1% (vol/vol) NP-40, 0.25mmol L脱 氧胆酸钠, 150mmol L NaCl, 10% (vol/vol) 甘油, 5mmol L 2-巯基乙醇, 0. lmmol L AEBSF, 溶剂为 10mmol L、 pH7.5 Tris-HCL
端粒酶反应液 (反应液 T) 组成如下: 0.06mmol L dNTP, lnmol L dsTU, 1.5mmol L MgCl2, 63mmol/L KCl, lmmol/L EGTA-Na, O.lmg/ml BSA, 0.05% Tween20, 溶剂为 20mmol L、 pH8.0 Tris-HCl。
RE PCR反应液组成如下: 0.2mmol L dNTP, lU/50ul Taq酶, PCR引物 0.2umol L, 0.4xSYBR Green I, 2U/50ul BamHI, 50mmol L KCl, 1.5mmol L MgCl2, 0.05% Tween20,溶剂为 10mmol L、 pH9.0的 Tris-HCl 。
不含 BamHI的常规 PCR反应液组成: 0.2mmol L dNTP, lU/50ul Taq酶, PCR引物 0.2umol/L, 0.4xSYBR Green I, 50mmol L KCl, 1.5mmol/L MgCl2, 0.05% Tween20, 溶剂为 10mmol L、 pH9.0 的 Tris-HCl 。
人肺癌细胞株 A549细胞 (购自美国 ATCC) 于 24孔板中进行细胞培养, 10000个细胞 /孔, 共 8孔细胞。过夜培养后, 吸去培养液, 加入 200ul/孔裂解液 T, 反复吸打, 分别转移到 8个 1.5 ml离心管中, 冰上放置 10min, 4°C、 15000rpm离心 lOmin后, 取上清得到裂解上清液。
分别取 50ul裂解上清液加到 6个 0.2ml的固定有端粒酶引物的反应管中, 其中 4个再分别加 入 lnmol L dsTU, 另外 4个加入相当于 dsTU体积的 dd¾0对照, 30°C保温 30min, 再 60°C保温 30min, 吸干, 4管(2个含 dsTU, 2个 ddH20对照, 下同)加入不含 BamHI的常规 PCR反应液, 另 3管加入含 BamHI的 RE PCR反应液, 在荧光定量 PCR仪上, 按 37°C lOmin, 94 °C 3min, 再 40个循环的 94 °C 5 sec 63 °C 30sec, SYBR green I荧光定量分析。 结果如下:
反应体系 Ct-dsTU Ct-ddH20 常规 PCR 20.72 29.38 常规 PCR 20.53 29.49
RE PCR 29.21 29.55
RE PCR 29.05 29.42 可见, 2种体系 dd¾0对照的 Ct值(来源于引物二聚体) >29。常规 PCR, dsTU管 Ct值<21, 远远小于对照的, 说明含 lnmol L dsTU的裂解上清液的反应管在吸干后, 残留的痕量 dsTU有明 显扩增。 RE PCR dsTU管 0¾值>29, 与对照相当, 说明 RE PCR体系可以有效地切割控制残留的 痕量 dsTU造成的扩增本底。 实施例 2: 整合有 BamHI的 WATA体系, 可以除去痕量 PCR产物污染的干扰
引物、 探针序列、 反应管、 裂解液 T、 反应液 Τ、 常规 PCR反应液、 RE PCR反应液如同实 施例 1。
A549细胞及裂解上清液的制备同实施例 1。分别取 50ul裂解上清液加到 8个 0.2ml的固定有 端粒酶引物的反应管中, 其中 4个再分别加入稀释度为 10—7的扩增产物, 另外 4个加入相同体积 的 dd¾0对照, 30°C保温 30min, 再 60°C保温 30min, 吸干, 4管(2个含扩增产物, 2个 ddH20 对照, 下同)加入不含 BamHI的常规 PCR体系, 另 3管加入含 BamHI的 RE PCR体系, 在荧光 定量 PCR仪上, 按 37°C lOmin, 94 °C 3min, 再 40个循环的 94°C 5 sec 63°C30sec, SYBR green l 荧光定量分析。 结果如下:
反应体系 Ct-产物 Ct-ddH20 常规 PCR 15.39 29.54 常规 PCR 15.11 29.81
RE PCR 29.15 29.67
RE PCR 29.03 29.50 可见, 2种体系 ddH20对照的 Ct值(来源于引物二聚体) >29。常规 PCR, 扩增产物管 0¾值<16, 远远小于对照的, 说明稀释度为 10—7的扩增产物能够给常规 PCR体系造成严重假阳性污染, 而 RE/PCR扩增产物管 0¾值>29, 与对照相当, 说明 RE PCR体系可以有效地切割控制痕量的扩增 产物污染造成的假阳性。 实施例 3 WATA法检测人肺癌 A549细胞的端粒酶活性
引物、 探针序列、 反应管、 裂解液 T、 反应液 T、 RE PCR反应液如同实施例 1。
检测方法如下:
1 ) A549细胞用 24孔板 (约 10-10000个 /孔) 进行细胞培养, 吸去培养液, 加入 200ul/孔的 裂解液 T, 反复吸打, 转移到 1.5 ml 离心管中, 冰上放置 20min, 4°C、 15000 rpm离心 20min, 取上清, 得到裂解上清液。
2)取 50uL裂解上清液加入铺定 PCR管中,冰上放置 30min,吸干,加入 50uL含 lnmol/L dsTU 的反应液 T, 30°C30min, 60°C30min„
3 )吸干,加入 50uL RE PCR反应体系(PCR缓冲液、 0.2umol L PCR引物、 0.2mmol/L dNTP、 1U Taq酶、 2UBamHI),在 PCR仪上先 37°C lOmin, 94 °C 3min,然后进行 40个循环 94 °C 5 sec 63 °C 30sec, SYBR green l荧光定量分析。
4) 以裂解液和热灭活 (80°C 10mm) 的 1000个细胞裂解上清液做为阴性对照, 取代裂解上 清液, 进行上述 2) -3 ) 步的操作。
5 ) ¾ Ct fI<28, 判断为阳性, 0¾值>28, 判断为阴性
结果如下: 样品 α 结果判断
裂解液 29.55 阴性
10个细胞 27.76 阳性
100个细胞 24.19 阳性
1000个细胞 20.83 阳性
10000个细胞 17.21 阳性
热灭活 29.38 阴性
可见, WATA法对 10-10000个 Α549细胞都能检出端粒酶活性。 实施例 4: 批量制备的固定反应管的稳定性
引物、 探针序列、 反应管、 裂解液 Τ、 反应液 T、 RE PCR反应液如同实施例 1。
1) 取 24个反应管, 分成 6组, 4个 /组, 密封后, 分别在 37°C放置 1,2,3,4,5,6天, 记作组 1, 组 2, 组 3, 组 4, 组 5, 组 6。
2) 按实施例 1的方法准备好 A549细胞裂解上清液,共 2x lml, 其中 lml置于冰上备用, 做为阳 性对照; 另外 lml进行热灭活处理 (80°C 10mm), 做为阴性对照。
3) 按实施例 3的步骤 2)、 步骤 3 ) 进行操作, 每组反应管分别做 2个阳性对照, 2个阴性对照。
4) 以 0¾值≤28, 判断为阳性, 0¾值>28, 判断为阴性。
结果如下:
Figure imgf000009_0001
可见, 批量制备的固定反应管在 37°C放置 1~4天, 对端粒酶活性检测结果基本无影响, 但 在 37°C放置 5天及以上, 对检测结果有严重影响。 实施例 5: 以 WATA法检测人表皮鳞状细胞癌细胞株 A431细胞的端粒酶活性
引物、 探针序列、 反应管、 裂解液 T、 反应液 T、 RE PCR反应液如同实施例 1。
检测方法如下:
A431细胞用 24孔板(约 10-10000个 /孔)进行细胞培养, 吸去培养液, 加入 200ul/孔的裂解 液 T, 反复吸打, 转移到 1.5 ml离心管中, 冰上放置 20min, 4°C、 15000 rpm 离心 20min, 取上 清, 得到裂解上清液。 以下操作同实施例 3, 以 0¾值≤28, 判断为阳性, 0¾值>28, 判断为阴性。
结果如下:
Figure imgf000009_0002
可见, WATA法对 10-10000个 A431细胞都能检出端粒酶活性。 实施例 6 : WATA检测试剂盒
8人份的试剂盒, 组成如下:
组分 功能 包装规格 1 ) 前处理液浓缩液 样品前处理, 收集、 富集、 洗涤细胞等 I X 1.7ml
使用前需用 ddH20稀释 50倍
2) 裂解液 T 裂解细胞 I X 1.7ml
直接使用
3 ) 反应液 T 端粒 G序列延伸反应及模板探针杂交结合 I X 0.45ml
直接使用
4) RE PCR反应液 酶切及 PCR扩增 I X 0.45ml
直接使用
5 ) 阴性对照 热灭活的 1000个 A549细胞裂解上清液 I X 0.12ml
直接使用
6) 阳性对照 新鲜冻存的 1000个 A549细胞裂解上清液 I X 0.12ml
直接使用
7) 反应管 固定有端粒酶引物 1 X 8
直接使用
8 ) 封口膜 反应管封口 3
直接使用
9) 说明书 操作说明、 注意事项等 1
前处理液浓缩液组成: 50xPBS+50g L DTT, 稀释 50倍后即为 lxPBS+lg L DTT; lxPBS组 成如下: NaC1 137mM, KC1 2.7mM, Na2HP04 10mM, KH2P04 1.8mM, 溶剂为蒸馏水;
引物序列、 裂解液 T、 反应液 T、 RE PCR反应液组成同实施例 1。
操作步骤:
1 ) 将试剂盒从冻存环境中取出, 室温下融解, 暂存于 4°C。
2) 用 83ml ddH20把前处理液浓缩液稀释 50倍成前处理液, 暂存于 4°C。
3 ) 收集样品, 样品可以是培养细胞、 组织, 也可以是痰液、 全血 (加抗凝剂)、 尿样等。
样品量建议: 培养细胞量约 10~106个 之间, 组织大小约 O.lcm3, 痰液约 2ml, 全血约 0.5ml, 尿样约 10ml。
样品预处理方法: 悬浮培养的细胞, 离心收集后, 重悬于 10ml前处理液; 组织块浸泡在 10ml 前处理液中, 剪碎; 痰液加 10ml前处理液, 37°C振荡约 10mm至痰液完全溶解; 全血直接加 10ml前处理液; 尿样离心后, 沉淀重悬于 10ml前处理液; 以上均再离心弃上清, 沉淀进入 下一步操作。
4) 上述沉淀加 200ul/样品的裂解液 T, 反复吸打后转移至 1.5ml离心管, 冰上放置 20mm, 4°C、 15000 rpm 离心 20min, 取上清, 得到裂解上清液。
5 ) 取 50uL裂解上清液加入铺定 PCR管中, 冰上放置 30min, 吸干, 加入 50uL含 lnmol L dsTU 的反应液 T, 30°C30min, 60 °C 30min„
6) 吸干, 加入 50uL RE/PCR反应体系 (PCR缓冲液、 0.2umol L PCR引物、 0.2mmol L dNTP、 1U Taq酶、 2U BamHI),在 PCR仪上先 37°C 10min, 94 °C 3min,然后进行 35个循环 94°C 5 sec 63 °C 30sec, SYBR green I荧光定量分析。
7) 对照设置: 以阴性对照和阳性对照, 取代裂解上清液, 进行上述 5 ) 〜- 6) 步的操作。
8 ) ¾ Ct fI<28, 判断为阳性, 0¾值>28, 判断为阴性。 实施例 6 : 以 WATA端粒酶活性检测试剂盒检测人胚肾细胞株 293T细胞的端粒酶活性
293T细胞 (细胞购自美国 ATCC) 用 24孔板 (约 1-106个 /孔) 进行细胞培养。 试剂盒及操 作步骤见实施例 5。 1000个细胞裂解上清液的热灭活处理同实施例 3。
结果如下:
Figure imgf000010_0001
103个细胞 20.18 阳性
104个细胞 16.79 阳性
105个细胞 14.35 阳性
106个细胞 14.82 阳性
阴性对照 29.67 阴性
阳性对照 20.44 阳性
可见, WATA试剂盒对 10-106个 293T细胞都能检出端粒酶活性, 但当样品细胞数达到或超 过 105个之后, Ct值不再明显减少, 说明扩增限制因素已由端粒 G序列延伸转变到模板探针, 即 全部的模板探针都已被结合吸附, 因此, 虽然更高的端粒酶活性导致的更多的端粒 G序列延伸, 但不能继续导致 PCR模板量的增加。 实施例 7: 以 WATA端粒酶活性检测试剂盒检测人宫颈癌细胞株 Hela细胞的端粒酶活性
Hela细胞 (细胞购自美国 ATCC) 用 24孔板 (约 10-105个 /孔) 进行细胞培养。 试剂盒及操 作步骤见实施例 5。 1000个细胞裂解上清液的热灭活处理同实施例 3。
结果如下:
Figure imgf000011_0001
且在这 ^ 、范围内, 细胞数越 多, 则 Ct值越低, 暗示 WATA端粒酶活性检测具有用于定 检测的价值。 实施例 8: 以 WATA端粒酶活性检测试剂盒检测人乳腺癌细胞株 MCF-7细胞的端粒酶活性
MCF-7细胞 (细胞购自美国 ATCC) 用 24孔板 (约 10~105个 /孔) 进行细胞培养。 试剂盒及 操作步骤见实施例 5。 1000个细胞裂解上清液的热灭活处理同实施例 3。
结果如下:
Figure imgf000011_0002
可见, WATA试剂盒对 10-106个 MCF-7细胞都能检出端粒酶活性, 且在这 ^ -范围内, 细胞数 , 则 Ct值越低, 暗示 WATA端粒酶活性检测具有用于定量检测的价值。 实施例 9: 以 WATA端粒酶活性检测试剂盒检测肺癌患者痰液标本的端粒酶活性
肺癌患者 20例为组织穿刺活检确诊处在 I期, 尚未进行手术。 痰液均为清晨新鲜痰液。 试剂盒及操作步骤见实施例 5。
20例肺癌患者中检测阳性结果为 16例, 阴性 4例; 2例正常人 (吸烟有痰、 近期体检健康) 对照的检测结果均为阴性: 样品 /对照 Ct 结果判断 阴性对照 29.68 阴性
阳性对照 20.84 阳性
肺癌患者 JFK-ZJL-201 16.33 阳性
肺癌患者 JFK-ZJL-202 19.58 阳性
肺癌患者 JFK-ZJL-203 26.54 阳性
肺癌患者 JFK-ZJL-204 18.29 阳性
肺癌患者 JFK-ZJL-205 30.43 阴性
肺癌患者 JFK-ZJL-206 31.76 阴性
肺癌患者 JFK-ZJL-207 24.99 阳性
肺癌患者 JFK-ZJL-208 27.86 阳性
肺癌患者 JFK-ZJL-209 19.19 阳性
肺癌患者 JFK-ZJL-210 16.93 阳性
肺癌患者 JFK-ZJL-211 17.40 阳性
肺癌患者 JFK-ZJL-212 26.62 阳性
肺癌患者 JFK-ZJL-213 21.52 阳性
肺癌患者 JFK-ZJL-214 28.74 阴性
肺癌患者 JFK-ZJL-215 18.47 阳性
肺癌患者 JFK-ZJL-216 20.78 阳性
肺癌患者 JFK-ZJL-217 29.85 阴性
肺癌患者 JFK-ZJL-218 27.22 阳性
肺癌患者 JFK-ZJL-219 26.59 阳性
肺癌患者 JFK-ZJL-220 20.55 阳性
正常人 JFK-ZJN-001 28.96 阴性
正常人 JFK-ZJN-002 29.75 阴性
可见 WATA法能够从多数肺癌患者的新鲜痰液中检测出端粒酶活性。 实施例 10: 以 WATA端粒酶活性检测试剂盒检测宫颈癌手术切除组织
宫颈癌患者 10例的手术切除组织冻存于 -80°C。 取约 30 mg冻存宫颈组织, 用无菌眼科剪剪 碎, 力 Π 10ml前处理液, 离心, 弃上清, 加 200ul裂解液 T, 冰浴 30 mm, 以下操作按实施例 5的 操作步骤进行。 试剂盒同实施例 5。
10例宫颈癌患者组织的 WATA端粒酶活性检测结果均为阳性:
Figure imgf000012_0001
可见 WATA法能够从宫颈癌患者的手术分离的冻存癌组织中检测出端粒酶活性。 实施例 11 : 以 WATA端粒酶活性检测试剂盒检测 ALT+肺癌细胞株 (K-LU-1细胞) ALT (端粒延伸替代机制)是端粒酶阴性的癌细胞延伸和维持端粒 DNA长度的机制。 SK-LU-1 (细胞购自美国 ATCC) 是一种已知的 ALT+细胞用 24孔板(约 10-105个 /孔)进行细胞培养。 试 剂盒及操作步骤见实施例 5。 1000个 SK-LU-1细胞裂解上清液的热灭活处理同实施例 3。
结果如下:
Figure imgf000013_0001
可见, 10-105个 SK-LU-1细胞的 WATA检测都呈阴性结果, 再次验证了 WATA端粒酶活性 检测的特异性。 实施例 12: 以 TaqMan探针替代 SYBR Green I染料, WATA端粒酶活性检测效果
弓 I物、 探针序列、 反应管、 裂解液 T、 反应液 T、 RE/PCR体系同实施例 1, RE PCR体系中以 0.5umol L TaqMan探针 (序列为: 5'-FAM-
TAACCCTAACCCTAACCCTAACCCTAACCC-TAMRA-3 ' ) 取代 SYBR green I。 细胞为 A549细 胞。 检测方法同实施例 3, 以 FAM荧光定量分析取代 SYBR green I分析, 以 0值≤30, 判断为 阳性, 0值>30或无 Ct, 判断为阴性;
结果如下:
Figure imgf000013_0002
可见, 使用 TaqMan的 WATA法对 10-10000个 A549细胞都能检出端粒酶活性。

Claims

权 利 要 求 书
1. 一种免洗涤铺定延伸端粒亲和扩增端粒酶的方法,所述方法是将待测样品的细胞裂解上清液加 入固定有端粒酶引物的 PCR反应管中, 冰上放置使端粒酶与引物结合, 吸干上清后, 加入由 模板探针、 抑制探针、 缓冲液和 dNTP组成的端粒酶反应体系, 在 30~37°C保温进行端粒 G序 列延伸反应, 随即在 55~65°C保温进行杂交反应, 之后吸干, 加入含有限制性内切酶和 PCR 引物的 PCR反应液, 先以 37°C保温 10分钟, 随即进行 PCR反应, PCR反应产物用于荧光定 量或琼脂糖凝胶电泳分析;
所述端粒酶引物序列如下:
5, - TCCGTCGAGC AGAGTTAGGGTTAG- 3,;
所述模板探针序列如下:
5'-CCGTCACCCTGGATGCTGTAGGATCCCTAACCCTAACCCTAACCCTAACCCTAACCCTA iGGATCGCTCGCGGCTCTT -3';
述抑制探针序列如下:
5'- TAGGGTTAGGGATCCTACA -3';
所述 PCR引物序列如下:
5 ' -CCGTC ACCCTGGATGCTGTAGG -3' ,
5 ' - AAGAGCCGCGAGCGATCCTT - 3'。
2. 如权利要求 1所述的方法, 其特征在于所述方法如下:
( 1 ) 合成端粒酶引物, 将其固定到 PCR反应管中, 得到铺定 PCR管;
(2) 分别合成模板探针和抑制探针;
(3 ) 将模板探针和抑制探针复性结合形成双链 DNA, 记作 dsTU;
(4) 取待测样本, 加入裂解液, 反复吸打, 转移至离心管中, 冰上放置 lOmin, 4°C离心, 取上清液, 得到裂解上清液;
(5 ) 取裂解上清液至铺定 PCR管中, 轻轻振荡后, 冰上放置 30min, 吸干, 加入由缓冲液、 dNTP和 dsTU配制的端粒酶反应液, 30~37°C 30~60min, 55-65 °C 15~30min, 吸干管 内液体, 加入由缓冲液、 dNTP、 Taq酶、 PCR引物、 SYBR green I或 TaqMan探针及 BamHI酶所配制的 RE/PCR反应液, 在 PCR仪上进行如下程序: 37°C酶切 5~15min, 92~95°C预变性 2~5min, 然后 35个循环的 92~95°C3~30sec, 55-65 °C 20~60sec; 扩增 产物用于荧光定量分析。
3. 如权利要求 2所述的方法, 其特征在于步骤 (5 ) 中所述端粒酶反应液组成如下: 0.06mmol/L dNTP, lnmol/L dsTU, 1.5mmol/L MgCl2, 63mmol/L KC1, lmmol/L EGTA-Na, O.lmg/ml BSA, 0.05% Tween20, 溶剂为 20mmol/L、 pH8.0 Tris- HC1。
4. 如权利要求 2所述的方法, 其特征在于步骤(5 ) 中所述 RE/PCR反应液组成如下: 0.2mmOl/L dNTP, lU/50ul Taq酶, PCR引物 0.2umol/L, 0.4xSYBR Green I, 2U/50ul BamHI, 50mmol/L KC1, 1.5mmol/L MgCl2, 0.05% Tween20, 溶剂为 10mmol/L、 pH9.0的 Tris- HC1 。
5. 一种免洗涤铺定延伸端粒亲和扩增检测端粒酶活性的试剂盒,主要包括固定有端粒酶引物的铺 定 PCR管, 模板探针、 抑制探针、 PCR引物, 端粒酶反应缓冲液、 RE/PCR反应缓冲液, 以 及 Taq酶和 BamHI酶;
其特征在于:
所述端粒酶引物序列如下:
5, -TCCGTCGAGC AGAGTTAGGGTTAG- 3,;
所述模板探针序列如下:
AGGATCGCTCGCGGCTCTT -3';
述抑制探针序列如下:
5'- TAGGGTTAGGGATCCTACA -3';
所述 PCR引物序列如下:
5 ' -CCGTC ACCCTGGATGCTGTAGG -3' ,
5 ' - AAGAGCCGCGAGCGATCCTT -3';
所述端粒酶反应缓冲液组成如下: 1.5mmol/L MgCl2, 63mmol/L KC1, lmmol/L EGTA-Na, O.lmg/ml BSA, 0.05% Tween20, 溶剂为 20mmol/L、 pH8.0 Tris- HC1。
所述 RE/PCR反应缓冲液组成如下: 50mmol/L KCl, 1.5mmol/L MgCl2, 0.05% Tween20, 溶 剂为 10mmol/L、 pH9.0的 Tris- HC1 。
6. 如权利要求 5所述的试剂盒,其特征在于所述试剂盒中还包括细胞裂解液,组成如下: lmmol/L MgCl2, lmmol/L EGTA-Na, 1%ΝΡ-40, 0.25mmol/L脱氧胆酸钠, 150mmol/L NaCl, 10% 甘 油, 5mmol/L 2-巯基乙醇, 0. lmmol/L AEBSF, 溶剂为 10mmol/L、 pH7.5 Tris- HC1。
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CN103343119B (zh) * 2013-06-07 2016-04-20 浙江今复康生物科技有限公司 端粒c序列单链dna的亲和介导扩增方法及检测试剂盒
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1108789A2 (en) * 1999-12-16 2001-06-20 F. Hoffmann-La Roche Ag Quantitation of hTERT mRNA Expression
CN102876792A (zh) * 2012-09-27 2013-01-16 浙江今复康生物科技有限公司 一种端粒酶的aetca检测试剂盒及检测方法
CN103333958A (zh) * 2013-06-07 2013-10-02 浙江今复康生物科技有限公司 免洗涤锚定延伸端粒亲和扩增检测端粒酶的方法及试剂盒
CN103343119A (zh) * 2013-06-07 2013-10-09 浙江今复康生物科技有限公司 端粒c序列单链dna的亲和介导扩增方法及检测试剂盒

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102443631A (zh) * 2011-11-13 2012-05-09 浙江理工大学 植物端粒酶活性的检测方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1108789A2 (en) * 1999-12-16 2001-06-20 F. Hoffmann-La Roche Ag Quantitation of hTERT mRNA Expression
CN102876792A (zh) * 2012-09-27 2013-01-16 浙江今复康生物科技有限公司 一种端粒酶的aetca检测试剂盒及检测方法
CN103333958A (zh) * 2013-06-07 2013-10-02 浙江今复康生物科技有限公司 免洗涤锚定延伸端粒亲和扩增检测端粒酶的方法及试剂盒
CN103343119A (zh) * 2013-06-07 2013-10-09 浙江今复康生物科技有限公司 端粒c序列单链dna的亲和介导扩增方法及检测试剂盒

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
LIN, ZIYU ET AL.: "Development in Mammalian Telomerase Activity Research", HEILONGJIANG ANIMAL SCIENCE AND VETERINARY MEDICINE, no. 7, 31 July 2012 (2012-07-31), pages 40 - 42 *
OHYASHIKI, K. ET AL.: "Cytological Detection of Telomerase Activity Using an in Situ Telomeric Repeat Amplification Protocol Assay", CANCER RES, vol. 57, no. 11, 31 December 1997 (1997-12-31), pages 2100 - 2103 *

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