Using the purified VP1 protein of Asia 1 type foot-and-mouth disease virus as the antigen, the purified monoclonal antibody was labeled by the sodium periodate method and the monoclonal antibody competitive ELISA was ...Using the purified VP1 protein of Asia 1 type foot-and-mouth disease virus as the antigen, the purified monoclonal antibody was labeled by the sodium periodate method and the monoclonal antibody competitive ELISA was established in this study. Ten positive porcine foot-and-mouth disease serums and more than two hundreds negative serum were tested, and the results were the same as the background of samples. The sensitivity test and replicate test indicated that this method was stable and sensitive, which was suitable for monitoring Asia 1 type porcine foot-and-mouth disease virus antibody.展开更多
Recently, serum Golgi protein 73 （GP73） levels have been found to be elevated in patients with hepatocellu- lar carcinoma （HCC）, and GP73 has been proposed as a novel marker for HCC. However, GP73 levels in patien...Recently, serum Golgi protein 73 （GP73） levels have been found to be elevated in patients with hepatocellu- lar carcinoma （HCC）, and GP73 has been proposed as a novel marker for HCC. However, GP73 levels in patients remain controversial due to the specificity of the anti-GP73 antibody-based enzyme linked immunosorbent as- say （ELISA）. Therefore, an anti-GP73 antibody with high specificity was highly demanded. In the present study, by hybridoma screening, we generated an anti-GP73 monoclonal antibody （mAb） designated as 6A2 using recom- binant GP73 protein produced by prokaryotic expression. The specificity of 6A2 was evaluated by Western blot- ting, immunohistochemistry and immunoprecipitation. The results showed that 6A2 recognized GP73 in both native and denatured forms. In addition, we have developed a sandwich ELISA using 6A2 and GP73 polyclonal antibody generated in New Zealand white rabbits according to standard procedures, and measured the serum GP73 level of patients using this assay. Our results showed that serum GP73 levels of HCC patients were significantly higher than those of healthy controls （P = 0.0036）. Furthermore, for the first time, GP73 serum level was found to be elevated in patients with breast cancer compared with healthy controls （P = 0.0172）.展开更多
A monoclonal antibody (MAb) specific for the bluetongue virus (BTV) group specific antigen (VP7) was characterized for its reactivity with purified virus and recombinant BTV VP7 (rVP7) protein and its suitability for ...A monoclonal antibody (MAb) specific for the bluetongue virus (BTV) group specific antigen (VP7) was characterized for its reactivity with purified virus and recombinant BTV VP7 (rVP7) protein and its suitability for use in the sandwich ELISA.The MAb,designated as 5B5 was specific to VP7 and belongs to IgG2a subclass and was selected for the development of the sELISA in this study.The MAb had a titer of 1:25 with BTV and 1:2 with the rVP7 protein.The sELISA is based on capturing of BTV antigen with VP7 specific MAb followed by detection using BTV polyclonal antiserum raised in rabbits.The assay was evaluated with six cell culture adapted serotypes of BTV that have been isolated from India,1,2,15,17,18 and 23.The assay could detect BTV antigen as early as day 8 in blood.It was also successfully applied for the detection of BTV group specific antigen in clinical samples of blood,washed RBCs,buffy coat and plasma.A total of 102 field samples from animals,suspected of being infected with BTV,were tested and 29.42% were positive.The blood samples were also amplified in cell culture which improved the sensitivity of the assay.Results confirmed that the sELISA is rapid and specific.展开更多
A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybrid...A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybridoma cell line producing antibody specific for spermidine was cultured in vitro and after i. p. into mice, the ascitic fluid gave suitably high dilution titres (1: 106) by enzyme immunoassay. This monoclonal antibody is of IgG1 class and the bimolecular compleex with molecular weight of 52KD and 27 KD. The monoclonal antibody was clearly specific to spermidine comparing with spermine or putriscine. Monclonal antibody may prove to be useful in the rapid diagnosis and evaluation of patients with cancer.展开更多
Aggregate amyloid beta protein1-42 (Aβ1-42) can typically be found in the early stage of Alzheimer’s disease (AD). Aβ1-42 self-assembles and is highly toxic to neurons. Thus, recognizing aggregated Aβ1-42 is very ...Aggregate amyloid beta protein1-42 (Aβ1-42) can typically be found in the early stage of Alzheimer’s disease (AD). Aβ1-42 self-assembles and is highly toxic to neurons. Thus, recognizing aggregated Aβ1-42 is very important for elucidation of Aβ1-42 structure and for the diagnosis of AD. In this study, the specificity of the 79-3 monoclonal antibody against soluble aggre- gate Aβ1-42 was measured by sandwich Enzyme-Linked Immuno Sorbent Assay (ELISA). Eight monoclonal antibodies against both soluble aggregates and amorphous aggregates were used as primary antibodies. Soluble aggregates and amorphous aggregates were used as antigen. As secondary antibody, HRP was labeled with the 79-3 monoclonal antibody. The reactivity of the 79-3 monoclonal antibody against soluble aggregates was confirmed in all combinations, but little reactivity against amorphous aggregates was found. Furthermore, we performed the above sandwich ELISA using the 37-11 antibody, which is reactive against large oval aggregates (LOA) that occur in micro aggregates, instead of the 79-3 antibody. The 77-3 antibody is 1 of the 8 monoclonal antibodies against soluble aggregates;amorphous aggregates also reacted with the 37-11 antibody. These results indicated that soluble aggregates are specifically recognized by a combination of different antibodies. The combined use of these antibodies can be applied to the diagnosis of AD and to defining the structure of the Aβ1-42.展开更多
The anti-CCA McAb Dot-was performedfor the henosis of schisto-somiasis after the further investigation on the Md.it shows high specificity and sensitivity.The detections in the different endemic areas show that all fo...The anti-CCA McAb Dot-was performedfor the henosis of schisto-somiasis after the further investigation on the Md.it shows high specificity and sensitivity.The detections in the different endemic areas show that all foe results coincide withlaw of epidemiology,in hyperendemic area with schistosomiasis the pesitive rate is over90%,in the maine enhac area is 80%,in the area with schistosomiasis basicolly eli-minated its peitive rate is Only 8.8%.Furthermore in cohort with pet history the po-sitive rate Of Dot-ELISA is significantly lower than that of IHA, and in cohort withoutpet history there is no signifort difference between Dot-ELISA the IHA. Dot-ELISAis suitable for field detections.It appears to be a simple,quick and cheap method whichis avt to be mastered.展开更多
Five monoclonal antibodies（Mabs） to nuclear protein of avain influenza virus（AIV） were developed by syncretizing SP 2/0 and the spleen cells from BALB of mice immuized with H9 subtype AIV. Specificity of these Mab...Five monoclonal antibodies（Mabs） to nuclear protein of avain influenza virus（AIV） were developed by syncretizing SP 2/0 and the spleen cells from BALB of mice immuized with H9 subtype AIV. Specificity of these Mabs were identified by immunofluorescent assay（IFA） and enzyme linked immunosorbent assay （ELISA）. These five Mabs which were named as AIV-NP-2C3, AIV-NP-6A5, AIV-NP-3 H9, AIV-NP-7B4, AIV-NP-2H4 could react with all viruses of AIV-H9 strains in tests. The result of Western blotting showed that only the 60 ku protein antigen of AIV-H9 could be recognized by the Mabs but never recognized by New castle disease virus, REV and infectious bursa disease virus. The result of preliminary application showed that avian influenza viruses could be deetected bv Mabs in IFA and ELISA. All these Mabs will probably play important roles in preventing and monitoring avian influenza viruses.展开更多
To prepare monoclonal antibodies （MAb） and antisera specific for Escherichia coli （E.coli） O157, and to develop a sandwich enzyme-linked immunosorbent assay （ELISA） to detect Eocoli O157 in foods. Methods Spleen...To prepare monoclonal antibodies （MAb） and antisera specific for Escherichia coli （E.coli） O157, and to develop a sandwich enzyme-linked immunosorbent assay （ELISA） to detect Eocoli O157 in foods. Methods Spleen cells from BALB/c mice immunized with the somatic antigen of E.coli O157：H7 were fused with routine Sp2/0 myeloma cells. The hybridoma cell line specific for E.coli O157 was established after having been subcloned. Antisera specific for E.coli O157 was prepared by intravenous injection into New Zealand rabbits with a stain of E.coli O157：H7. The sandwich ELISA was developed with the polyclonal antibody as the capture antibody and the MAb 3A5 as the detection antibody. The inoculated ground poultry meat and pasteurized miLk were tested to confirm efficiency of the method. Results MAb 3A5 specific for E.coli O157 and O 113：H21 belonged to subtype IgM. The ascetic titers of the antibody was 1：1× 10^6. No cross-reactivity of the MAb was observed with strains of Salmonella spp, Yersinia enterocolitica, Shigella dysenteriae, etc. The purified polyclonal antibody had a titer of 1： 1× 10^5 with E.coli O 157. The detection limit of this sandwich ELISA was 10^3- 10^4 cfu E.coli O157/mL in pure culture with a high specificity, which was characterized by every non-O157 strain with negative response. With 10h enrichment procedure, E.coli O157：H7 recovered well from inoculated ground poultry meat and pasteurized milk at levels of 0.1 cfu/g and 0.1 cfu/mL. Conclusion MAb 3A5 specific for E.coli O 157 and O 113：H21 can be produced by immunizing BALB/c mice with a strain of E.coli O157：H7. Then a sandwich ELISA can be developed with the polyclonal antibody as the capture antibody and the MAb 3A5 as the detection antibody. The method is proved to be a sensitive and specific technique to detect low number of E.coli O157 in food.展开更多
为给猫传染性腹膜炎病毒(FIPV)的流行和地理分布提供有价值的检测手段,以FIPV S蛋白为包被抗原,利用FIPV的特异性单克隆抗体(FIPV MAb 3D8)为竞争抗体,经条件优化,建立一种快速检测FIPV抗体的竞争ELISA法。优化结果表明最佳条件为:包被...为给猫传染性腹膜炎病毒(FIPV)的流行和地理分布提供有价值的检测手段,以FIPV S蛋白为包被抗原,利用FIPV的特异性单克隆抗体(FIPV MAb 3D8)为竞争抗体,经条件优化,建立一种快速检测FIPV抗体的竞争ELISA法。优化结果表明最佳条件为:包被抗原质量浓度10μg/mL,血清稀释度1∶4;FIPV MAb 3D8稀释倍数1∶100,酶标二抗稀释倍数1∶5000;CBS在37℃包被1 h,5%BSA在37℃封闭2 h,FIPV MAb 3D8在37℃孵育1 h,TMD底物显色液37℃避光5 min。临界值PI≥25.76%时为阳性,PI<20.22%为阴性。该方法特异性较强,重复性较好。利用该方法和已发表的其他方法同时对来自宠物医院的62份临床血清样本进行检测,总体符合率为85.5%,表明该方法准确性较高。本研究建立了快速准确测定FIPV抗体的竞争ELISA方法,适用于临床样本检测,为猫传染性腹膜炎的鉴定、防控和流行病学调查提供支持。展开更多
Rice ragged stunt virus（RRSV） is a serious rice disease in Asia, causing serious yield losses on rice. The capsid protein（CP） gene of the major outer capsid protein of RRSV was expressed in Escherichia coli BL21（...Rice ragged stunt virus（RRSV） is a serious rice disease in Asia, causing serious yield losses on rice. The capsid protein（CP） gene of the major outer capsid protein of RRSV was expressed in Escherichia coli BL21（DE3） using the pMAL-C2 X expression vector. The recombinant protein was used as the immunogen to immunize BALB/c mice. A hybridoma cell line 8A12 secreting monoclonal antibody（MAb） against RRSV was obtained by fusing mouse myeloma cells（Sp 2/0） with spleen cells from the immunized BALB/c mice. Western blot analysis showed that the MAb 8A12 can specifically react with RRSV CP. Using the MAb, an antigen-coated-plate enzyme-linked immunosorbent assay（ACP-ELISA）, a dot enzyme-linked immunosorbent assay（dot-ELISA）, and immunocapture-RT-PCR（IC-RT-PCR） assay were developed to detect RRSV. The established ACP-ELISA, dot-blot ELISA and IC-RT-PCR methods could detect RRSV in infected rice tissue crude extracts with dilutions of 1：40 960, 1：1 280 and 1：655 360（w/v, g mL-1）, respectively. The ACP-ELISA and dot-blot ELISA methods could detect RRSV in infected insect vector crude extracts with dilutions of 1：12 800 and 1：1 600（an individual planthopper μL-1）, respectively. The field survey revealed that Rice ragged stunt disease occurs on rice in Hainan, Yunnan, Guangxi, Sichuan, Guizhou, Fujian, Hunan, Jiangxi and Zhejiang in China.展开更多
Aphid-borne Zucchini yellow mosaic virus （ZYMV） is one of the most economically important viruses of cucurbitaceous plants. To survey and control this virus, it is necessary to develop an efficient detection techniq...Aphid-borne Zucchini yellow mosaic virus （ZYMV） is one of the most economically important viruses of cucurbitaceous plants. To survey and control this virus, it is necessary to develop an efficient detection technique. Using purified ZYMV virion and the conventional hybridoma technology, three hybridoma cell lines （16A11, 5A7 and 3B8） secreting monoclonal antibodies （MAbs） against ZYMV Zhejiang isolate were obtained. The working titers of the ascitic fluids secreted by the three hybridoma cell lines were up to 10^-7 by indirect enzyme-linked immunosorbent assay （ELISA）. All MAbs were isotyped as IgG1, kappa light chain. Western blot analysis indicated that the MAb 3B8 could specifically react with the coat protein of ZYMV while MAbs 5A7 and 16A11 reacted strongly with a protein of approximately 51 kDa from the ZYMV-infected leaf tissues. According to this molecular weight, we consider this reactive protein As likely to be the HC-Pro protein. Using these three MAbs, we have now developed five detection assays, i.e., antigen-coated-plate ELISA （ACP-ELISA）, dot-ELISA, tissue blot-ELISA, double-antibody sandwich ELISA （DAS-ELISA）, and immunocapture-RT-PCR （IC-RT-PCR）, for the sensitive, specific, and easy detection of ZYMV. The sensitivity test revealed that ZYMV could be readily detected respectively by ACP-ELISA, dot-ELISA, DAS-ELISA and IC-RT-PCR in 1：163840, 1：2560, 1：327680 and 1：1 310720 （w/v, g mL-1） diluted crude extracts from the ZYMV-infected plants. We demonstrated in this study that the dot-ELISA could also be used to detect ZYMV in individual viruliferous aphids. A total of 275 cucurbitaceous plant samples collected from the Zhejiang, Jiangsu, Shandong and Hainan provinces, China, were screened for the presence of ZYMV with the described assays. Our results showed that 163 of the 275 samples （59%） were infected with ZYMV. This finding indicates that ZYMV As now widely present in cucurbitaceous crops in China. RT-PCR followed by DNA sequencing and sequence analyses confirmed the accuracy of the five assays. We consider that these detection assays can significantly benefit the control of ZYMV in China.展开更多
In the present study,a total of 24 MAbs were produced against bluetongue virus (BTV) by polyethyleneglycol (PEG) mediated fusion method using sensitized lymphocytes and myeloma cells. All these clones were characteriz...In the present study,a total of 24 MAbs were produced against bluetongue virus (BTV) by polyethyleneglycol (PEG) mediated fusion method using sensitized lymphocytes and myeloma cells. All these clones were characterized for their reactivity to whole virus and recombinant BTV-VP7 protein,titres,isotypes and their reactivity with 24 BTV-serotype specific sera in cELISA. Out of 24 clones,a majority of them (n = 18) belong to various IgG subclasses and the remaining (n = 6) to the IgM class. A panel of eight clones reactive to both whole BTV and purified rVP7 protein were identified based on their reactivity in iELISA. For competitive ELISA,the clone designated as 4A10 showed better inhibition to hyperimmune serum of BTV serotype 23. However,this clone showed a variable percent of inhibition ranging from16.6% with BTV 12 serotype to 78.9% with BTV16 serotype using 24 serotype specific sera of BTV originating from guinea pig at their lowest dilutions. From the available panel of clones,only 4A10 was found to have a possible diagnostic application.展开更多
Tomato yellow leaf curl virus（TYLCV）is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein（CP）gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21（...Tomato yellow leaf curl virus（TYLCV）is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein（CP）gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21（DE3）using pET-32a as the expression vector.The recombinant protein was purified through Ni＋-NTA affinity column and used to immunize BALB/c mice.Three hybridoma cell lines（2B2,2E3 and 3E10）secreting monoclonal antibodies（MAbs）against TYLCV CP were obtained by fusing mouse myeloma cells（Sp 2/0）with spleen cells from the immunized BALB/c mouse.The titers of ascitic fluids of three MAbs ranged from 10-6 to 10-7 in indirect-ELISA.Isotypes and subclasses of all the MAbs belonged to IgG1,κ light chain.Triple antibody sandwich enzyme-linked immunosorbent assay（TAS-ELISA）showed that the MAb 3E10 could react with five begomoviruses infecting tomato,while the other two（2B2 and 2E3）mainly reacted with TYLCV.TAS-ELISA was set up using the MAb 3E10,and the established method could successfully detect virus in plant sap at 1：2 560（w/v,g mL-1）.Detection of field samples showed that begomoviruses were common in tomato crops in Zhejiang Province,China.展开更多
Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strain...Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strains prevalent in China.Methods：Monoclonal antibodies（MAbs）specific to rabies virus were produced and characterized by enzyme linked immunosorbent assay（ELISA）,isotyping,affinity assay,immunofluorescence assay（IFA）,and immunocytochemistry.The MAb,whose affinity was higher for antigen,was used to establish an antigen captureELISA（AC-ELISA）detection system and test the efficiency by using clinical samples.Results：The heavy chain subclasses of two MAbs were all determined to be IgG2a.The 3C7 MAb showed stronger reactivity with rabies virus protein than the 2C5 MAb in an ELISA analysis,whereas the 3C7 MAb showed the highest affinity for antigen.IFA and immunocytochemistry results also indicated that the two MAbs could recognize rabies virus protein in its native form in cell samples.Data obtained using clinical samples showed that rabies virus could be detected by AC-ELISA detection system using the 3C7 MAb.Conclusion：It was potentially useful for the further development of highly sensitive,easily handled,and relatively rapid detection kits/tools for rabies surveillance in those areas where rabies is endemic,especially in China.展开更多
基金Supported by National High-tech R&D Program (863) Subsidized Project(2006AA10A204)Special Fund for Basic Scientific Research-related Subsidy of State-level and Public-welfare Scientific Research Institutes~~
文摘Using the purified VP1 protein of Asia 1 type foot-and-mouth disease virus as the antigen, the purified monoclonal antibody was labeled by the sodium periodate method and the monoclonal antibody competitive ELISA was established in this study. Ten positive porcine foot-and-mouth disease serums and more than two hundreds negative serum were tested, and the results were the same as the background of samples. The sensitivity test and replicate test indicated that this method was stable and sensitive, which was suitable for monitoring Asia 1 type porcine foot-and-mouth disease virus antibody.
基金supported by the Science and Technology Foundation of Nanjing Medical University (No. 07NMUZ005).
文摘Recently, serum Golgi protein 73 （GP73） levels have been found to be elevated in patients with hepatocellu- lar carcinoma （HCC）, and GP73 has been proposed as a novel marker for HCC. However, GP73 levels in patients remain controversial due to the specificity of the anti-GP73 antibody-based enzyme linked immunosorbent as- say （ELISA）. Therefore, an anti-GP73 antibody with high specificity was highly demanded. In the present study, by hybridoma screening, we generated an anti-GP73 monoclonal antibody （mAb） designated as 6A2 using recom- binant GP73 protein produced by prokaryotic expression. The specificity of 6A2 was evaluated by Western blot- ting, immunohistochemistry and immunoprecipitation. The results showed that 6A2 recognized GP73 in both native and denatured forms. In addition, we have developed a sandwich ELISA using 6A2 and GP73 polyclonal antibody generated in New Zealand white rabbits according to standard procedures, and measured the serum GP73 level of patients using this assay. Our results showed that serum GP73 levels of HCC patients were significantly higher than those of healthy controls （P = 0.0036）. Furthermore, for the first time, GP73 serum level was found to be elevated in patients with breast cancer compared with healthy controls （P = 0.0172）.
文摘A monoclonal antibody (MAb) specific for the bluetongue virus (BTV) group specific antigen (VP7) was characterized for its reactivity with purified virus and recombinant BTV VP7 (rVP7) protein and its suitability for use in the sandwich ELISA.The MAb,designated as 5B5 was specific to VP7 and belongs to IgG2a subclass and was selected for the development of the sELISA in this study.The MAb had a titer of 1:25 with BTV and 1:2 with the rVP7 protein.The sELISA is based on capturing of BTV antigen with VP7 specific MAb followed by detection using BTV polyclonal antiserum raised in rabbits.The assay was evaluated with six cell culture adapted serotypes of BTV that have been isolated from India,1,2,15,17,18 and 23.The assay could detect BTV antigen as early as day 8 in blood.It was also successfully applied for the detection of BTV group specific antigen in clinical samples of blood,washed RBCs,buffy coat and plasma.A total of 102 field samples from animals,suspected of being infected with BTV,were tested and 29.42% were positive.The blood samples were also amplified in cell culture which improved the sensitivity of the assay.Results confirmed that the sELISA is rapid and specific.
文摘A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybridoma cell line producing antibody specific for spermidine was cultured in vitro and after i. p. into mice, the ascitic fluid gave suitably high dilution titres (1: 106) by enzyme immunoassay. This monoclonal antibody is of IgG1 class and the bimolecular compleex with molecular weight of 52KD and 27 KD. The monoclonal antibody was clearly specific to spermidine comparing with spermine or putriscine. Monclonal antibody may prove to be useful in the rapid diagnosis and evaluation of patients with cancer.
文摘Aggregate amyloid beta protein1-42 (Aβ1-42) can typically be found in the early stage of Alzheimer’s disease (AD). Aβ1-42 self-assembles and is highly toxic to neurons. Thus, recognizing aggregated Aβ1-42 is very important for elucidation of Aβ1-42 structure and for the diagnosis of AD. In this study, the specificity of the 79-3 monoclonal antibody against soluble aggre- gate Aβ1-42 was measured by sandwich Enzyme-Linked Immuno Sorbent Assay (ELISA). Eight monoclonal antibodies against both soluble aggregates and amorphous aggregates were used as primary antibodies. Soluble aggregates and amorphous aggregates were used as antigen. As secondary antibody, HRP was labeled with the 79-3 monoclonal antibody. The reactivity of the 79-3 monoclonal antibody against soluble aggregates was confirmed in all combinations, but little reactivity against amorphous aggregates was found. Furthermore, we performed the above sandwich ELISA using the 37-11 antibody, which is reactive against large oval aggregates (LOA) that occur in micro aggregates, instead of the 79-3 antibody. The 77-3 antibody is 1 of the 8 monoclonal antibodies against soluble aggregates;amorphous aggregates also reacted with the 37-11 antibody. These results indicated that soluble aggregates are specifically recognized by a combination of different antibodies. The combined use of these antibodies can be applied to the diagnosis of AD and to defining the structure of the Aβ1-42.
文摘The anti-CCA McAb Dot-was performedfor the henosis of schisto-somiasis after the further investigation on the Md.it shows high specificity and sensitivity.The detections in the different endemic areas show that all foe results coincide withlaw of epidemiology,in hyperendemic area with schistosomiasis the pesitive rate is over90%,in the maine enhac area is 80%,in the area with schistosomiasis basicolly eli-minated its peitive rate is Only 8.8%.Furthermore in cohort with pet history the po-sitive rate Of Dot-ELISA is significantly lower than that of IHA, and in cohort withoutpet history there is no signifort difference between Dot-ELISA the IHA. Dot-ELISAis suitable for field detections.It appears to be a simple,quick and cheap method whichis avt to be mastered.
基金Supported by the National Key Technologies Research and Develop-ment Program of China during the 10th Five-Year Plan Period(2004BA519A05)Technologies Research and Development Program of China during the 10th Five-Year Plan Period in Jiangsu Province(BE2002346).~~
文摘Five monoclonal antibodies（Mabs） to nuclear protein of avain influenza virus（AIV） were developed by syncretizing SP 2/0 and the spleen cells from BALB of mice immuized with H9 subtype AIV. Specificity of these Mabs were identified by immunofluorescent assay（IFA） and enzyme linked immunosorbent assay （ELISA）. These five Mabs which were named as AIV-NP-2C3, AIV-NP-6A5, AIV-NP-3 H9, AIV-NP-7B4, AIV-NP-2H4 could react with all viruses of AIV-H9 strains in tests. The result of Western blotting showed that only the 60 ku protein antigen of AIV-H9 could be recognized by the Mabs but never recognized by New castle disease virus, REV and infectious bursa disease virus. The result of preliminary application showed that avian influenza viruses could be deetected bv Mabs in IFA and ELISA. All these Mabs will probably play important roles in preventing and monitoring avian influenza viruses.
文摘To prepare monoclonal antibodies （MAb） and antisera specific for Escherichia coli （E.coli） O157, and to develop a sandwich enzyme-linked immunosorbent assay （ELISA） to detect Eocoli O157 in foods. Methods Spleen cells from BALB/c mice immunized with the somatic antigen of E.coli O157：H7 were fused with routine Sp2/0 myeloma cells. The hybridoma cell line specific for E.coli O157 was established after having been subcloned. Antisera specific for E.coli O157 was prepared by intravenous injection into New Zealand rabbits with a stain of E.coli O157：H7. The sandwich ELISA was developed with the polyclonal antibody as the capture antibody and the MAb 3A5 as the detection antibody. The inoculated ground poultry meat and pasteurized miLk were tested to confirm efficiency of the method. Results MAb 3A5 specific for E.coli O157 and O 113：H21 belonged to subtype IgM. The ascetic titers of the antibody was 1：1× 10^6. No cross-reactivity of the MAb was observed with strains of Salmonella spp, Yersinia enterocolitica, Shigella dysenteriae, etc. The purified polyclonal antibody had a titer of 1： 1× 10^5 with E.coli O 157. The detection limit of this sandwich ELISA was 10^3- 10^4 cfu E.coli O157/mL in pure culture with a high specificity, which was characterized by every non-O157 strain with negative response. With 10h enrichment procedure, E.coli O157：H7 recovered well from inoculated ground poultry meat and pasteurized milk at levels of 0.1 cfu/g and 0.1 cfu/mL. Conclusion MAb 3A5 specific for E.coli O 157 and O 113：H21 can be produced by immunizing BALB/c mice with a strain of E.coli O157：H7. Then a sandwich ELISA can be developed with the polyclonal antibody as the capture antibody and the MAb 3A5 as the detection antibody. The method is proved to be a sensitive and specific technique to detect low number of E.coli O157 in food.
文摘为给猫传染性腹膜炎病毒(FIPV)的流行和地理分布提供有价值的检测手段,以FIPV S蛋白为包被抗原,利用FIPV的特异性单克隆抗体(FIPV MAb 3D8)为竞争抗体,经条件优化,建立一种快速检测FIPV抗体的竞争ELISA法。优化结果表明最佳条件为:包被抗原质量浓度10μg/mL,血清稀释度1∶4;FIPV MAb 3D8稀释倍数1∶100,酶标二抗稀释倍数1∶5000;CBS在37℃包被1 h,5%BSA在37℃封闭2 h,FIPV MAb 3D8在37℃孵育1 h,TMD底物显色液37℃避光5 min。临界值PI≥25.76%时为阳性,PI<20.22%为阴性。该方法特异性较强,重复性较好。利用该方法和已发表的其他方法同时对来自宠物医院的62份临床血清样本进行检测,总体符合率为85.5%,表明该方法准确性较高。本研究建立了快速准确测定FIPV抗体的竞争ELISA方法,适用于临床样本检测,为猫传染性腹膜炎的鉴定、防控和流行病学调查提供支持。
基金supported by the National Basic Research Program of China(2010CB126203)the special fund for Agro-scientific Research in the Public Interest,China(201003031)+1 种基金Earmarked Funds for Modern Agro-industry Technology Research SystemZhejiang Provincial Natural Science Foundation of China(Z3090039)
文摘Rice ragged stunt virus（RRSV） is a serious rice disease in Asia, causing serious yield losses on rice. The capsid protein（CP） gene of the major outer capsid protein of RRSV was expressed in Escherichia coli BL21（DE3） using the pMAL-C2 X expression vector. The recombinant protein was used as the immunogen to immunize BALB/c mice. A hybridoma cell line 8A12 secreting monoclonal antibody（MAb） against RRSV was obtained by fusing mouse myeloma cells（Sp 2/0） with spleen cells from the immunized BALB/c mice. Western blot analysis showed that the MAb 8A12 can specifically react with RRSV CP. Using the MAb, an antigen-coated-plate enzyme-linked immunosorbent assay（ACP-ELISA）, a dot enzyme-linked immunosorbent assay（dot-ELISA）, and immunocapture-RT-PCR（IC-RT-PCR） assay were developed to detect RRSV. The established ACP-ELISA, dot-blot ELISA and IC-RT-PCR methods could detect RRSV in infected rice tissue crude extracts with dilutions of 1：40 960, 1：1 280 and 1：655 360（w/v, g mL-1）, respectively. The ACP-ELISA and dot-blot ELISA methods could detect RRSV in infected insect vector crude extracts with dilutions of 1：12 800 and 1：1 600（an individual planthopper μL-1）, respectively. The field survey revealed that Rice ragged stunt disease occurs on rice in Hainan, Yunnan, Guangxi, Sichuan, Guizhou, Fujian, Hunan, Jiangxi and Zhejiang in China.
基金supported by the National Natural Science Foundation of China(31272015)the National Basic Research Program(973)of China(2014CB138400)the Special Fund for Agro-scientific Research in the Public Interest,China(201303021,201303028)
文摘Aphid-borne Zucchini yellow mosaic virus （ZYMV） is one of the most economically important viruses of cucurbitaceous plants. To survey and control this virus, it is necessary to develop an efficient detection technique. Using purified ZYMV virion and the conventional hybridoma technology, three hybridoma cell lines （16A11, 5A7 and 3B8） secreting monoclonal antibodies （MAbs） against ZYMV Zhejiang isolate were obtained. The working titers of the ascitic fluids secreted by the three hybridoma cell lines were up to 10^-7 by indirect enzyme-linked immunosorbent assay （ELISA）. All MAbs were isotyped as IgG1, kappa light chain. Western blot analysis indicated that the MAb 3B8 could specifically react with the coat protein of ZYMV while MAbs 5A7 and 16A11 reacted strongly with a protein of approximately 51 kDa from the ZYMV-infected leaf tissues. According to this molecular weight, we consider this reactive protein As likely to be the HC-Pro protein. Using these three MAbs, we have now developed five detection assays, i.e., antigen-coated-plate ELISA （ACP-ELISA）, dot-ELISA, tissue blot-ELISA, double-antibody sandwich ELISA （DAS-ELISA）, and immunocapture-RT-PCR （IC-RT-PCR）, for the sensitive, specific, and easy detection of ZYMV. The sensitivity test revealed that ZYMV could be readily detected respectively by ACP-ELISA, dot-ELISA, DAS-ELISA and IC-RT-PCR in 1：163840, 1：2560, 1：327680 and 1：1 310720 （w/v, g mL-1） diluted crude extracts from the ZYMV-infected plants. We demonstrated in this study that the dot-ELISA could also be used to detect ZYMV in individual viruliferous aphids. A total of 275 cucurbitaceous plant samples collected from the Zhejiang, Jiangsu, Shandong and Hainan provinces, China, were screened for the presence of ZYMV with the described assays. Our results showed that 163 of the 275 samples （59%） were infected with ZYMV. This finding indicates that ZYMV As now widely present in cucurbitaceous crops in China. RT-PCR followed by DNA sequencing and sequence analyses confirmed the accuracy of the five assays. We consider that these detection assays can significantly benefit the control of ZYMV in China.
文摘In the present study,a total of 24 MAbs were produced against bluetongue virus (BTV) by polyethyleneglycol (PEG) mediated fusion method using sensitized lymphocytes and myeloma cells. All these clones were characterized for their reactivity to whole virus and recombinant BTV-VP7 protein,titres,isotypes and their reactivity with 24 BTV-serotype specific sera in cELISA. Out of 24 clones,a majority of them (n = 18) belong to various IgG subclasses and the remaining (n = 6) to the IgM class. A panel of eight clones reactive to both whole BTV and purified rVP7 protein were identified based on their reactivity in iELISA. For competitive ELISA,the clone designated as 4A10 showed better inhibition to hyperimmune serum of BTV serotype 23. However,this clone showed a variable percent of inhibition ranging from16.6% with BTV 12 serotype to 78.9% with BTV16 serotype using 24 serotype specific sera of BTV originating from guinea pig at their lowest dilutions. From the available panel of clones,only 4A10 was found to have a possible diagnostic application.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest from the Ministry of Agriculture,China(201003065)
文摘Tomato yellow leaf curl virus（TYLCV）is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein（CP）gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21（DE3）using pET-32a as the expression vector.The recombinant protein was purified through Ni＋-NTA affinity column and used to immunize BALB/c mice.Three hybridoma cell lines（2B2,2E3 and 3E10）secreting monoclonal antibodies（MAbs）against TYLCV CP were obtained by fusing mouse myeloma cells（Sp 2/0）with spleen cells from the immunized BALB/c mouse.The titers of ascitic fluids of three MAbs ranged from 10-6 to 10-7 in indirect-ELISA.Isotypes and subclasses of all the MAbs belonged to IgG1,κ light chain.Triple antibody sandwich enzyme-linked immunosorbent assay（TAS-ELISA）showed that the MAb 3E10 could react with five begomoviruses infecting tomato,while the other two（2B2 and 2E3）mainly reacted with TYLCV.TAS-ELISA was set up using the MAb 3E10,and the established method could successfully detect virus in plant sap at 1：2 560（w/v,g mL-1）.Detection of field samples showed that begomoviruses were common in tomato crops in Zhejiang Province,China.
基金supported by the National High Technology Research and Development Program of China(863 Program,No.2007AA02Z418)
文摘Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strains prevalent in China.Methods：Monoclonal antibodies（MAbs）specific to rabies virus were produced and characterized by enzyme linked immunosorbent assay（ELISA）,isotyping,affinity assay,immunofluorescence assay（IFA）,and immunocytochemistry.The MAb,whose affinity was higher for antigen,was used to establish an antigen captureELISA（AC-ELISA）detection system and test the efficiency by using clinical samples.Results：The heavy chain subclasses of two MAbs were all determined to be IgG2a.The 3C7 MAb showed stronger reactivity with rabies virus protein than the 2C5 MAb in an ELISA analysis,whereas the 3C7 MAb showed the highest affinity for antigen.IFA and immunocytochemistry results also indicated that the two MAbs could recognize rabies virus protein in its native form in cell samples.Data obtained using clinical samples showed that rabies virus could be detected by AC-ELISA detection system using the 3C7 MAb.Conclusion：It was potentially useful for the further development of highly sensitive,easily handled,and relatively rapid detection kits/tools for rabies surveillance in those areas where rabies is endemic,especially in China.
