The monoclonal antibodies consist of an innovative form of immunotherapy,capable of defeating several diseases,such as cancer.It is an emergent and important theme,that advances evaluation,challenges,and future perspe...The monoclonal antibodies consist of an innovative form of immunotherapy,capable of defeating several diseases,such as cancer.It is an emergent and important theme,that advances evaluation,challenges,and future perspectives with high relevance to identify gaps in recent studies and to consolidate this general theme in only one research.Its action in Chronic and Acute Lymphoid Leukemia has been evaluated in several clinical trials,which were selected between 2022 and 2023,in order to understand better the monoclonal antibodies that were most studied.The biopharmaceutical compounds Ibrutinib,Obinutuzumab,Rituximab,Venetoclax,and Inotuzumab Ozogamicin were the ones that most appeared in the most recent publications,indicating the importance of amplifying the studies.The action mechanisms that are used imply that their combined use has more success in the disease remission,showing a lower recurrence,adverse effects,and toxicity.Besides the adverse effects and overwhelming prices of the treatment,these immunotherapies results are promising,amplifying the survival rates,improving the patient’s life quality,and resulting in a precision medicine,aiming a custom treatment.The future perspectives on this therapy consist of its application in the public health system,with patients being able to be submitted to this treatment without any costs and receive a better life quality.展开更多
Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and...Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and treatment(Wang et al. 2023). Due to its enormous economic and social impact, it is listed as a notifiable animal disease by the World Organization for Animal Health(Costard et al. 2013). Although ASF has been present in Sub-Saharan Africa since its first discovery in Kenya.展开更多
Porcine deltacoronavirus(PDCoV)is an emerging swine enteropathogenic coronavirus that can cause acute diarrhea and vomiting in newborn piglets and poses a potential risk for cross-species transmission.It is necessary ...Porcine deltacoronavirus(PDCoV)is an emerging swine enteropathogenic coronavirus that can cause acute diarrhea and vomiting in newborn piglets and poses a potential risk for cross-species transmission.It is necessary to develop an effective serological diagnostic tool for the surveillance of PDCoV infection and vaccine immunity effects.In this study,we developed a monoclonal antibody-based competitive ELISA(cELISA)that selected the purified recombinant PDCoV nucleocapsid(N)protein as the coating antigen to detect PDCoV antibodies.To evaluate the diagnostic performance of the cELISA,122 swine serum samples(39 positive and 83 negative)were tested and the results were compared with an indirect immunofluorescence assay(IFA)as the reference method.By receiver operating characteristic(ROC)curve analysis,the optimum cutoff value of percent inhibition(PI)was determined to be 26.8%,which showed excellent diagnostic performance,with an area under the curve(AUC)of 0.9919,a diagnostic sensitivity of 97.44%and a diagnostic specificity of 96.34%.Furthermore,there was good agreement between the cELISA and virus neutralization test(VNT)for the detection of PDCoV antibodies,with a coincidence rate of 92.7%,and theκanalysis showed almost perfect agreement(κ=0.851).Overall,the established cELISA showed good diagnostic performance,including sensitivity,specificity and repeatability,and can be used for diagnostic assistance,evaluating the response to vaccination and assessing swine herd immunity.展开更多
[Objective] This study was conducted to find out an approach for determining trimethoprim residues in water. [Method] Trimethoprim antigen was prepared through a series of reactions from trimethoprim hapten which was ...[Objective] This study was conducted to find out an approach for determining trimethoprim residues in water. [Method] Trimethoprim antigen was prepared through a series of reactions from trimethoprim hapten which was generated through the reaction between trimethoprim and maleic anhydride. And trimethoprim monoclonal antibodies were prepared by animal immune, and used to prepare ELISA kit to detect trimethoprim residues in water. Finally, the limit of detection （LED） of the ELISA kit was determined. [Result] The standard curve covered a concentration range of 0-80 μg/L. The LeD of trimethoprim in water using the ELISA kit was 2.34 μg/kg; the IC50 （half maximal inhibitory concentration） was 4.8 μg/L; the recovery rate of added trimethoprim standard ranged from 60.5% to 79.7%; within-and among-batches RSD was less than 10%. The trimethoprim monoclonal antibody was specific, as the cross-reactivity rate of trimethoprim antibody and diaveridine was less than 1%. The stability tests revealed that the ELISA kit was stable after being stored at 4 ℃ for 12 months. [Conclusion] The results will provide references for controlling the abuse of trimethoprim.展开更多
Therapeutic monoclonal antibodies have become one of the central components of the healthcare system and continuous efforts are made to bring innovative antibody therapeutics to patients in need.It is equally critical...Therapeutic monoclonal antibodies have become one of the central components of the healthcare system and continuous efforts are made to bring innovative antibody therapeutics to patients in need.It is equally critical to acquire sufficient knowledge of their molecular structure and biological functions to ensure the efficacy and safety by incorporating new detection approaches since new challenges like individual differences and resistance are presented.Conventional techniques for determining antibody disposition including plasma drug concentration measurements using LC-MS or ELISA,and tissue distribution using immunohistochemistry and immunofluorescence are now complemented with molecular imaging modalities like positron emission tomography and near-infrared fluorescence imaging to obtain more dynamic information,while methods for characterization of antibody’s interaction with the target antigen as well as visualization of its cellular and intercellular behavior are still under development.Recent progress in detecting therapeutic antibodies,in particular,the development of methods suitable for illustrating the molecular dynamics,is described here.展开更多
Murine monoclonal antibody (MoAb) BB4.3, raised against the human gastric cancer cell line BGC823, was puriffied with Protein A-Sepharose CL-4B affinity chromatography and identified as IgG2a. It was then conjugated w...Murine monoclonal antibody (MoAb) BB4.3, raised against the human gastric cancer cell line BGC823, was puriffied with Protein A-Sepharose CL-4B affinity chromatography and identified as IgG2a. It was then conjugated with a hematoporphyrin derivative (HPD) by using carbodiimide. The qualitative analysis of this conjugate showed that the amount of free HPD was negligible and there were no IgG aggregates among the conjugates. The conjugate retained both the antibody and photochemical activity of HPD.In vitro, the phototoxic effect of this HPD-BB4.3 conjugate on target cells was about 15 times higher than that of free HPD. The quality of selective photocytotoxicity was proven by the greater cytotoxi-city this conjugate showed than that of corresponding normal mouse IgG (NIgG) conjugated with HPD. It showed less cytotoxicity to colon cancer cell line B-80 (negative reaction to MoAb BB4.3) than to BGC825. Moreover, its cytotoxicity to BGC823 cells could be blocked specifically by excess BB4.3 antibody, but not by another MoAb 3G9, which combines with BGC823 at different binding sites from MoAb BB4.3.Nude mice inoculated with 2 × 10- BGC823 cells were given HPD-BB4.3, HPD, HPD-NIgG, HPD plus BB4.3 and PBS, respectively then exposed to light. Four out of six animals treated with the HPD-BB4.3 conjugate remained tumor-free for a long period. Although two developed tumors, there was a significant difference between the HPD-BB4.3-treated group and all the control groups in tumor induction time, tumor growth rate, and survival time (p<0.001). The HPD-BB4.3 conjugate inhibited the growth of established tumors by more than 40% in comparison with control groups (p<0.05).展开更多
Thirty-five hybridoma cell lines against cytoke-ratins, isolated from Hela cells and human cellus respectively, were generated by fusion of immunized spleen cells of BALB/C mice with P3×63-Ag8.653, a mouse myelom...Thirty-five hybridoma cell lines against cytoke-ratins, isolated from Hela cells and human cellus respectively, were generated by fusion of immunized spleen cells of BALB/C mice with P3×63-Ag8.653, a mouse myeloma cell line. Two of them (HI and C53) were characterized by indirect immu-nofluorescence, ABC immunostaining and immuno-blotting. The results of immunofluorescence and ABC immunostaining suggested that both monoclonal antibodies were specific for keratin-type intermediate filaments. However, the two monoclonal antibodies showed different specificities in normal tissues and neoplasms as observed on both frozen and deparaf-finized sections. In normal tissues, H1 stained transitional epithelium and all types of simple epithelium except endothelium and mesothelium but did not stain stratified squamous epithelium. In contrast, C35 recognized only stratified squamous epithelium, but failing to react with simple epithelium. Both monoclonal antibodies did not react with nonepithelia cells and tissues. In neoplasms, H1 stained varieties of adenocaroinomas and C35 recognized merely squamous cell carcinomas. Therefore, all the epithelial tissues can nearly be recognized by combination of the two monoclonal antibodies. All the results indicated that H1 and C35 can be used in cell biology and histology studies, and can be used in differential diagnosis of adenocarcinoma and squamous cell carcinoma in pathology.展开更多
In the present study, an indirect assay was employed to investigate 5 anti-gastric cancer monoclonal antibodies for their cytotoxic potential as ricin A chain-containing immunotoxins. The tumor cell, were treated with...In the present study, an indirect assay was employed to investigate 5 anti-gastric cancer monoclonal antibodies for their cytotoxic potential as ricin A chain-containing immunotoxins. The tumor cell, were treated with dilutions of tested antibody followed by ricin A chain coupled to goat anti-mouse immunoglobulin. The cytotoxic effect was determined with tetrazolium colorimetric assay. The results showed that among the 5 antibodies chosen, MGb2 and MG7 could be well used for preparation of effective A chain immunotoxins.展开更多
Serum ALD-A of 57 patients with HCC and 43 of other diseases were measured by ALD-A-McAb linked with 425I-staphylococcus A protein. The results showed that the ALD-A in patient with HCC was significantly elevated as c...Serum ALD-A of 57 patients with HCC and 43 of other diseases were measured by ALD-A-McAb linked with 425I-staphylococcus A protein. The results showed that the ALD-A in patient with HCC was significantly elevated as compared with controls and that in patients with cholangiocarcinoma, gastrointestinal cancer without hepatic metastasis, cirrhosis. CAH and benign GI diseases. There was no statistical difference between ALD-A in patients with HCC and that in cases of cirrhosis with liver failure and that in cases of metastatic liver carcinoma. It was noted that diagnostic sensitivity of ALD-A in AFP (+) HCC was 73.9% and that in AFP (-) HCC was 81.8% 1-6 patients with HCC were treated by hepatic arterial embolization combined with chemotherapy. ALD-A in patients after the treatment decreased significantly than that before treatment, furthermore, advantages of the method are discussed.展开更多
The localization of three monoclonal antibodies (MAb) against gastric cancer was studied on two human gastric cancer cell lines by immunoelectron microscopic technique. It has shown that the corresponding antigens of ...The localization of three monoclonal antibodies (MAb) against gastric cancer was studied on two human gastric cancer cell lines by immunoelectron microscopic technique. It has shown that the corresponding antigens of MAb 3G9 and 3H11 were distributed on the microvilli (M) and non-microvillus (NM) plasma membrane of target cells, with various M to NM ratios depending on the MAbs and target cells used. However, the corresponding antigens of MAb PD4 was only localized on the surface of round or finger-like bulges of target cells and never on the microvilli and non-microvillous plasma membrane. Since the nature and function of these tumor antigens have not been identified yet, the implication of the different distributions of these antigens remians to be clarifated.展开更多
We developed two complement-fixing MoAbsHIMand HIM(murine)that were specifically reac-tive with chronic myelogenous leukemia (CML) cells.They were capable of fixing human or rabbit com-plement and suitable for CML cel...We developed two complement-fixing MoAbsHIMand HIM(murine)that were specifically reac-tive with chronic myelogenous leukemia (CML) cells.They were capable of fixing human or rabbit com-plement and suitable for CML cells purging of re-mission marrow from CML patients.HIMreactedwith majority leukemic cells form 7 out of 10 CMLpatients by complement-mediated cytotoxicity(C’MC)assay(positive cells 80%—90%),HIMreacted withmajority CML cells from 4 out of 5 CML by C’MCassay(positive cells 80%—90%).Treatment withHIMor HIMand human C’was capable of lysing97% of K562,U937,HL-60 and CML cells in a 20fold excess of unrelated cells by indirect FITC+EBstain.Using limited dilution culture,incubation withHIMand C’produced 1.5 logs inhibition of growthin K562 cells,and 1.9 logs in U937 cells,and withHIMand C’produced 2.9 logs inhibition in HL-60cells and 3.0 logs in U937 cells.Both MoAbs cocktailwas shown 1.8 logs in K562 cells and 3.2 logs in U937cells.They were no suppression on the growth o展开更多
α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment ...α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2 of anti-gastric tumor monoclonal antibody 3G9.The radiolabelled antibody was satisfactorily stable and immunoreactive.展开更多
This paper described T cell proliferative response by an alternative pathway in normal subjects and In patients with malignant diseases. Two McAbs, Anti-CCTl and Lo-CD2-act recognizing two distinct epitopes on E-recep...This paper described T cell proliferative response by an alternative pathway in normal subjects and In patients with malignant diseases. Two McAbs, Anti-CCTl and Lo-CD2-act recognizing two distinct epitopes on E-receptor (CD2) were used to costimulate PBMC. Proliferative responsiveness was measured by 3H-thymidine incorporation. It was found that 82% of 72 nonnal subjects gave proliferative response whereas only 23% of the 93 patients did. The average cpm±SD in patients with bladder cancer (118±2314), kidney cancer (1619±2719) or lymphoma (2518±4057) was significantly lower than that in normal subjects (4935±2314), (P<0.001). These results indicate that T cell proliferation through the alternative pathway was significantly depressed in patients with cancer, and this can be used as a new parameter to monitor the immune status of cancer patients.展开更多
Immunoconjugates are antibody-drug hybrid molecules which combine the exquisite selectivity or monoclonal antibodies with the potent toxicity of anticancer agents. A monoclonal antibody SZ39 against human brain glioma...Immunoconjugates are antibody-drug hybrid molecules which combine the exquisite selectivity or monoclonal antibodies with the potent toxicity of anticancer agents. A monoclonal antibody SZ39 against human brain gliomas was used as a drug carrier. Adriamycin (ADR) was bound covalently to SZ39 to form a SZ39-ADR conjugate. The cytotoxic activity of the SZ39-ADR conjugate was tested in vitro and demonstrated potent and specific killing of cells derived from a human malignant glioma. 50% inhibitory concentration (IC50) for SZ39-ADR to 'target' cells was 8.14×10-9 M. An index of specificity between 'target' and 'non-target' cells was calculated to be 88-fold. These data suggest that the SZ39-ADR may use as a potent and cell type-specific agent and is a likely candidate for the targeting chemotherapy of malignant gliotnas.展开更多
Athymic nude mice bearing subcutaneous and intracerebral human glioma xenografts were used to assess the therapeutic efficacy of monoclonal anti-body-adriamycin immunoconjugates against malignant gliomas in vivo. Immu...Athymic nude mice bearing subcutaneous and intracerebral human glioma xenografts were used to assess the therapeutic efficacy of monoclonal anti-body-adriamycin immunoconjugates against malignant gliomas in vivo. Immunoconjugates showed a significantly stronger antitumor effect with a T/C (treated/ control tumor volume) of 30% as compared with free drug (T/C of 84%). The targeting treatment with immunoconjugates significantly prolonged 54% of median survival time of nude mice. Side effects of immunoconjugates on the normal bone marrow and small intestines were much slighter than those of the free drug. The results of this study indicate that the use of monoclonal antibodies as carriers of anti-tumor agents may have many therapeutic advantages and potential for the treatment of brain gliomas.展开更多
Monoclonal antibodies against colon and pancreatic cancer, CL-2, CL-3, PS-9, PS-10, were used to detect the associated antigens in feces of patients with gastrointestinal carcinoma and non-cancer diseases. Binding inh...Monoclonal antibodies against colon and pancreatic cancer, CL-2, CL-3, PS-9, PS-10, were used to detect the associated antigens in feces of patients with gastrointestinal carcinoma and non-cancer diseases. Binding inhibition test by SABC-ELISA method were performed for the measurement of the antigen level. Results showed that the associated antigen detected in feces of patients with colon cancer were significantly higher than that of non-cancer disease or normal subjects. The positive rates were 61.1% as detected with CL-2; 53.4% with CL-3; 55.0%, PS-9; and 53.3% PS-10 in cancer patients while that in normal subjects were 7%; 9%; 8%; and 8% respectively. When 'cocktail' of CL-2, PS-9 and PS-10 were used, the positive rates were 92.5% in colon cancer and 14% in normal subjects. In seven out of the sixty patients with colon cancer studied who were graded as Dukes A, the results were all positive. The results seem superior to the serologic detection and may provide a promising new approach in the early diagnosis of colon cancer.展开更多
A convenient competitive enzyme-linked immunosorbent assay(ELISA) for ciprofloxacin(CPFX) was developed by using rabbit monoclonal antibodies(RabMAbs) against a hapten-protein conjugate of CPFX-bovine serum albumin(BS...A convenient competitive enzyme-linked immunosorbent assay(ELISA) for ciprofloxacin(CPFX) was developed by using rabbit monoclonal antibodies(RabMAbs) against a hapten-protein conjugate of CPFX-bovine serum albumin(BSA).The indirect competitive ELISA of CPFX had a concentration at 50% inhibition(IC50) of 1.47 ng/ml and a limit of detection(LOD) of 0.095 ng/ml.The mAb exhibited some cross-reactivity,however,not so high with enrofloxacin(28.8%),ofloxacin(13.1%),norfloxacin(11.0%),fleroxacin(22.6%),and pefloxacin(20.4%).And it showed almost no cross-reactivity with other antibiotics or sulfonamides evaluated in this study.The competitive ELISA kit developed here could be used as a screening tool to detect and control illegal addition of CPFX in food products.This kit had been applied to milk detection and the recovery rates from samples spiked by CPFX were in a range of 63.02%-84.60%,with coefficients of variation of less than 12.2%.展开更多
Since the approval of rituximab in 1997, monoclonal antibodies(mAbs) have become an increasingly important component of therapeutic regimens in oncology. The success of mAbs as a therapeutic class is a result of great...Since the approval of rituximab in 1997, monoclonal antibodies(mAbs) have become an increasingly important component of therapeutic regimens in oncology. The success of mAbs as a therapeutic class is a result of great strides that have been made in molecular biology and in biotechnology over the past several decades. Currently, there are 14 approved mAb products for oncology indications, and there are ten additional mAbs in late stages of clinical trials. Compared to traditional chemotherapeutic agents, mAbs have several advantages, including a long circulating half-life and high target specificity. Antibodies can serve as cytotoxic agents when administered alone, exerting a pharmacologic effect through several mechanisms involving the antigen binding(Fab) and/or Fc domains of the molecule, and mAbs may also be utilized as drug carriers, targeting a toxic payload to cancer cells. The extremely high affinity of mAbs for their targets, which is desirable with respect to pharmacodynamics(i.e., contributing to the high therapeutic selectivity of mAb), often leads to complex, non-linear, target-mediated pharmacokinetics. In this report, we summarize the pharmacokinetic and pharmacodynamics of mAbs that have been approved and of mAbs that are nearing approval for oncology indications, with particular focus on the molecular and cellular mechanisms responsible for their disposition and efficacy.展开更多
Cardiac troponin I(cTnI) was separated and purified from human left ventricular tissue by affinity chromatographic method and used to immunize Balb/c mice by intraperitoneal injection and four hybridoma cell lines, wh...Cardiac troponin I(cTnI) was separated and purified from human left ventricular tissue by affinity chromatographic method and used to immunize Balb/c mice by intraperitoneal injection and four hybridoma cell lines, which secreted monoclonal antibody(mAb) against human cTnI, were obtained by cell fusion, identification and cloning twice. Three mAbs(9F5, 2F11, 8C12) were produced from the ascites of Balb/c mice injected intraperitoneally the hybridoma cells and characterized by means of a surface plasmon resonance(SPR) biosensor. An optimal and specific sensing membrane for troponin I was prepared with staphylococcal protein A(SPA) as the intermediate layer and mAb against human cTnI as the capture antibody. On the basis of the sensing membrane, two modes of operation of the SPR biosensor were developed, i.e ., a direct detection of antigen antibody affinity and a sandwich assay. In the sandwich assay detection mode, the mAbs competition was measured by monitoring whether the secondary antibody had been attached to the cTnI already captured by the first antibody on the sensor surface. The SPR biosensor was shown to be able to directly detect the antigen antibody affinity and the order of the affinity was found to be 9F5>2F11>8C12. In the sandwich detection mode, it was found that the different epitopes on the cTnI molecules were recognized by the three mAbs respectively, but the asymmetrical competition was shown between 2F11 and 8C12 and no competition was found between 9F5 and 2F11 or 8c12. Based on these results, a double monoclonal sandwich immunoassay for cTnI was developed by using the optimal antibody pair of 9F5 and 2F11 and the SPR biosensor with SPA substrate membrane, which showed an excellent sensitivity of 0.8 μg/L for both the buffer and the serum samples compared with the direct detection of cTnI for the buffer with the lowest detection limit of 4 μg/L and conventional ELISA with the sensitivity of 1.9 μg/L.展开更多
文摘The monoclonal antibodies consist of an innovative form of immunotherapy,capable of defeating several diseases,such as cancer.It is an emergent and important theme,that advances evaluation,challenges,and future perspectives with high relevance to identify gaps in recent studies and to consolidate this general theme in only one research.Its action in Chronic and Acute Lymphoid Leukemia has been evaluated in several clinical trials,which were selected between 2022 and 2023,in order to understand better the monoclonal antibodies that were most studied.The biopharmaceutical compounds Ibrutinib,Obinutuzumab,Rituximab,Venetoclax,and Inotuzumab Ozogamicin were the ones that most appeared in the most recent publications,indicating the importance of amplifying the studies.The action mechanisms that are used imply that their combined use has more success in the disease remission,showing a lower recurrence,adverse effects,and toxicity.Besides the adverse effects and overwhelming prices of the treatment,these immunotherapies results are promising,amplifying the survival rates,improving the patient’s life quality,and resulting in a precision medicine,aiming a custom treatment.The future perspectives on this therapy consist of its application in the public health system,with patients being able to be submitted to this treatment without any costs and receive a better life quality.
基金supported by the National Key Research and Development Program of China (2021YFD1800100)the earmarked fund for China Agriculture Research System (CARS-35)。
文摘Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and treatment(Wang et al. 2023). Due to its enormous economic and social impact, it is listed as a notifiable animal disease by the World Organization for Animal Health(Costard et al. 2013). Although ASF has been present in Sub-Saharan Africa since its first discovery in Kenya.
基金supported by the National Key Research and Development Program(2023YFD1800501)the National Natural Science Foundation of China(32373030,32202787)+5 种基金the S&T Program of Hebei(21322401D)the Jiangsu Province Natural Sciences Foundation(BK20221432,BK20210158)the Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)3028)the Special Project of Northern Jiangsu(SZ-LYG202109)the Open Fund of Shaoxing Academy of Biomedicine of Zhejiang Sci-Tech University(SXAB202215)the Open Fund of Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases,Ministry of Agriculture and Rural Affairs(YDWS202213).
文摘Porcine deltacoronavirus(PDCoV)is an emerging swine enteropathogenic coronavirus that can cause acute diarrhea and vomiting in newborn piglets and poses a potential risk for cross-species transmission.It is necessary to develop an effective serological diagnostic tool for the surveillance of PDCoV infection and vaccine immunity effects.In this study,we developed a monoclonal antibody-based competitive ELISA(cELISA)that selected the purified recombinant PDCoV nucleocapsid(N)protein as the coating antigen to detect PDCoV antibodies.To evaluate the diagnostic performance of the cELISA,122 swine serum samples(39 positive and 83 negative)were tested and the results were compared with an indirect immunofluorescence assay(IFA)as the reference method.By receiver operating characteristic(ROC)curve analysis,the optimum cutoff value of percent inhibition(PI)was determined to be 26.8%,which showed excellent diagnostic performance,with an area under the curve(AUC)of 0.9919,a diagnostic sensitivity of 97.44%and a diagnostic specificity of 96.34%.Furthermore,there was good agreement between the cELISA and virus neutralization test(VNT)for the detection of PDCoV antibodies,with a coincidence rate of 92.7%,and theκanalysis showed almost perfect agreement(κ=0.851).Overall,the established cELISA showed good diagnostic performance,including sensitivity,specificity and repeatability,and can be used for diagnostic assistance,evaluating the response to vaccination and assessing swine herd immunity.
基金Supported by Beijing Municipal Science and Technology Project(Z151100002115059)~~
文摘[Objective] This study was conducted to find out an approach for determining trimethoprim residues in water. [Method] Trimethoprim antigen was prepared through a series of reactions from trimethoprim hapten which was generated through the reaction between trimethoprim and maleic anhydride. And trimethoprim monoclonal antibodies were prepared by animal immune, and used to prepare ELISA kit to detect trimethoprim residues in water. Finally, the limit of detection （LED） of the ELISA kit was determined. [Result] The standard curve covered a concentration range of 0-80 μg/L. The LeD of trimethoprim in water using the ELISA kit was 2.34 μg/kg; the IC50 （half maximal inhibitory concentration） was 4.8 μg/L; the recovery rate of added trimethoprim standard ranged from 60.5% to 79.7%; within-and among-batches RSD was less than 10%. The trimethoprim monoclonal antibody was specific, as the cross-reactivity rate of trimethoprim antibody and diaveridine was less than 1%. The stability tests revealed that the ELISA kit was stable after being stored at 4 ℃ for 12 months. [Conclusion] The results will provide references for controlling the abuse of trimethoprim.
基金We acknowledge financial support from the National Natural Science Foundation of China(81903574)the Fundamental Research Funds for the Central Universities(2019QNA7046,2020QNA7001).
文摘Therapeutic monoclonal antibodies have become one of the central components of the healthcare system and continuous efforts are made to bring innovative antibody therapeutics to patients in need.It is equally critical to acquire sufficient knowledge of their molecular structure and biological functions to ensure the efficacy and safety by incorporating new detection approaches since new challenges like individual differences and resistance are presented.Conventional techniques for determining antibody disposition including plasma drug concentration measurements using LC-MS or ELISA,and tissue distribution using immunohistochemistry and immunofluorescence are now complemented with molecular imaging modalities like positron emission tomography and near-infrared fluorescence imaging to obtain more dynamic information,while methods for characterization of antibody’s interaction with the target antigen as well as visualization of its cellular and intercellular behavior are still under development.Recent progress in detecting therapeutic antibodies,in particular,the development of methods suitable for illustrating the molecular dynamics,is described here.
文摘Murine monoclonal antibody (MoAb) BB4.3, raised against the human gastric cancer cell line BGC823, was puriffied with Protein A-Sepharose CL-4B affinity chromatography and identified as IgG2a. It was then conjugated with a hematoporphyrin derivative (HPD) by using carbodiimide. The qualitative analysis of this conjugate showed that the amount of free HPD was negligible and there were no IgG aggregates among the conjugates. The conjugate retained both the antibody and photochemical activity of HPD.In vitro, the phototoxic effect of this HPD-BB4.3 conjugate on target cells was about 15 times higher than that of free HPD. The quality of selective photocytotoxicity was proven by the greater cytotoxi-city this conjugate showed than that of corresponding normal mouse IgG (NIgG) conjugated with HPD. It showed less cytotoxicity to colon cancer cell line B-80 (negative reaction to MoAb BB4.3) than to BGC825. Moreover, its cytotoxicity to BGC823 cells could be blocked specifically by excess BB4.3 antibody, but not by another MoAb 3G9, which combines with BGC823 at different binding sites from MoAb BB4.3.Nude mice inoculated with 2 × 10- BGC823 cells were given HPD-BB4.3, HPD, HPD-NIgG, HPD plus BB4.3 and PBS, respectively then exposed to light. Four out of six animals treated with the HPD-BB4.3 conjugate remained tumor-free for a long period. Although two developed tumors, there was a significant difference between the HPD-BB4.3-treated group and all the control groups in tumor induction time, tumor growth rate, and survival time (p<0.001). The HPD-BB4.3 conjugate inhibited the growth of established tumors by more than 40% in comparison with control groups (p<0.05).
文摘Thirty-five hybridoma cell lines against cytoke-ratins, isolated from Hela cells and human cellus respectively, were generated by fusion of immunized spleen cells of BALB/C mice with P3×63-Ag8.653, a mouse myeloma cell line. Two of them (HI and C53) were characterized by indirect immu-nofluorescence, ABC immunostaining and immuno-blotting. The results of immunofluorescence and ABC immunostaining suggested that both monoclonal antibodies were specific for keratin-type intermediate filaments. However, the two monoclonal antibodies showed different specificities in normal tissues and neoplasms as observed on both frozen and deparaf-finized sections. In normal tissues, H1 stained transitional epithelium and all types of simple epithelium except endothelium and mesothelium but did not stain stratified squamous epithelium. In contrast, C35 recognized only stratified squamous epithelium, but failing to react with simple epithelium. Both monoclonal antibodies did not react with nonepithelia cells and tissues. In neoplasms, H1 stained varieties of adenocaroinomas and C35 recognized merely squamous cell carcinomas. Therefore, all the epithelial tissues can nearly be recognized by combination of the two monoclonal antibodies. All the results indicated that H1 and C35 can be used in cell biology and histology studies, and can be used in differential diagnosis of adenocarcinoma and squamous cell carcinoma in pathology.
文摘In the present study, an indirect assay was employed to investigate 5 anti-gastric cancer monoclonal antibodies for their cytotoxic potential as ricin A chain-containing immunotoxins. The tumor cell, were treated with dilutions of tested antibody followed by ricin A chain coupled to goat anti-mouse immunoglobulin. The cytotoxic effect was determined with tetrazolium colorimetric assay. The results showed that among the 5 antibodies chosen, MGb2 and MG7 could be well used for preparation of effective A chain immunotoxins.
文摘Serum ALD-A of 57 patients with HCC and 43 of other diseases were measured by ALD-A-McAb linked with 425I-staphylococcus A protein. The results showed that the ALD-A in patient with HCC was significantly elevated as compared with controls and that in patients with cholangiocarcinoma, gastrointestinal cancer without hepatic metastasis, cirrhosis. CAH and benign GI diseases. There was no statistical difference between ALD-A in patients with HCC and that in cases of cirrhosis with liver failure and that in cases of metastatic liver carcinoma. It was noted that diagnostic sensitivity of ALD-A in AFP (+) HCC was 73.9% and that in AFP (-) HCC was 81.8% 1-6 patients with HCC were treated by hepatic arterial embolization combined with chemotherapy. ALD-A in patients after the treatment decreased significantly than that before treatment, furthermore, advantages of the method are discussed.
文摘The localization of three monoclonal antibodies (MAb) against gastric cancer was studied on two human gastric cancer cell lines by immunoelectron microscopic technique. It has shown that the corresponding antigens of MAb 3G9 and 3H11 were distributed on the microvilli (M) and non-microvillus (NM) plasma membrane of target cells, with various M to NM ratios depending on the MAbs and target cells used. However, the corresponding antigens of MAb PD4 was only localized on the surface of round or finger-like bulges of target cells and never on the microvilli and non-microvillous plasma membrane. Since the nature and function of these tumor antigens have not been identified yet, the implication of the different distributions of these antigens remians to be clarifated.
文摘We developed two complement-fixing MoAbsHIMand HIM(murine)that were specifically reac-tive with chronic myelogenous leukemia (CML) cells.They were capable of fixing human or rabbit com-plement and suitable for CML cells purging of re-mission marrow from CML patients.HIMreactedwith majority leukemic cells form 7 out of 10 CMLpatients by complement-mediated cytotoxicity(C’MC)assay(positive cells 80%—90%),HIMreacted withmajority CML cells from 4 out of 5 CML by C’MCassay(positive cells 80%—90%).Treatment withHIMor HIMand human C’was capable of lysing97% of K562,U937,HL-60 and CML cells in a 20fold excess of unrelated cells by indirect FITC+EBstain.Using limited dilution culture,incubation withHIMand C’produced 1.5 logs inhibition of growthin K562 cells,and 1.9 logs in U937 cells,and withHIMand C’produced 2.9 logs inhibition in HL-60cells and 3.0 logs in U937 cells.Both MoAbs cocktailwas shown 1.8 logs in K562 cells and 3.2 logs in U937cells.They were no suppression on the growth o
文摘α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2 of anti-gastric tumor monoclonal antibody 3G9.The radiolabelled antibody was satisfactorily stable and immunoreactive.
文摘This paper described T cell proliferative response by an alternative pathway in normal subjects and In patients with malignant diseases. Two McAbs, Anti-CCTl and Lo-CD2-act recognizing two distinct epitopes on E-receptor (CD2) were used to costimulate PBMC. Proliferative responsiveness was measured by 3H-thymidine incorporation. It was found that 82% of 72 nonnal subjects gave proliferative response whereas only 23% of the 93 patients did. The average cpm±SD in patients with bladder cancer (118±2314), kidney cancer (1619±2719) or lymphoma (2518±4057) was significantly lower than that in normal subjects (4935±2314), (P<0.001). These results indicate that T cell proliferation through the alternative pathway was significantly depressed in patients with cancer, and this can be used as a new parameter to monitor the immune status of cancer patients.
文摘Immunoconjugates are antibody-drug hybrid molecules which combine the exquisite selectivity or monoclonal antibodies with the potent toxicity of anticancer agents. A monoclonal antibody SZ39 against human brain gliomas was used as a drug carrier. Adriamycin (ADR) was bound covalently to SZ39 to form a SZ39-ADR conjugate. The cytotoxic activity of the SZ39-ADR conjugate was tested in vitro and demonstrated potent and specific killing of cells derived from a human malignant glioma. 50% inhibitory concentration (IC50) for SZ39-ADR to 'target' cells was 8.14×10-9 M. An index of specificity between 'target' and 'non-target' cells was calculated to be 88-fold. These data suggest that the SZ39-ADR may use as a potent and cell type-specific agent and is a likely candidate for the targeting chemotherapy of malignant gliotnas.
文摘Athymic nude mice bearing subcutaneous and intracerebral human glioma xenografts were used to assess the therapeutic efficacy of monoclonal anti-body-adriamycin immunoconjugates against malignant gliomas in vivo. Immunoconjugates showed a significantly stronger antitumor effect with a T/C (treated/ control tumor volume) of 30% as compared with free drug (T/C of 84%). The targeting treatment with immunoconjugates significantly prolonged 54% of median survival time of nude mice. Side effects of immunoconjugates on the normal bone marrow and small intestines were much slighter than those of the free drug. The results of this study indicate that the use of monoclonal antibodies as carriers of anti-tumor agents may have many therapeutic advantages and potential for the treatment of brain gliomas.
文摘Monoclonal antibodies against colon and pancreatic cancer, CL-2, CL-3, PS-9, PS-10, were used to detect the associated antigens in feces of patients with gastrointestinal carcinoma and non-cancer diseases. Binding inhibition test by SABC-ELISA method were performed for the measurement of the antigen level. Results showed that the associated antigen detected in feces of patients with colon cancer were significantly higher than that of non-cancer disease or normal subjects. The positive rates were 61.1% as detected with CL-2; 53.4% with CL-3; 55.0%, PS-9; and 53.3% PS-10 in cancer patients while that in normal subjects were 7%; 9%; 8%; and 8% respectively. When 'cocktail' of CL-2, PS-9 and PS-10 were used, the positive rates were 92.5% in colon cancer and 14% in normal subjects. In seven out of the sixty patients with colon cancer studied who were graded as Dukes A, the results were all positive. The results seem superior to the serologic detection and may provide a promising new approach in the early diagnosis of colon cancer.
基金Project supported by the National High-Tech R&D Program (863) of China (No. 2007AA10Z436)the Important National Science and Technology Specific Projects of China (No. 2009ZX03012-010B)
文摘A convenient competitive enzyme-linked immunosorbent assay(ELISA) for ciprofloxacin(CPFX) was developed by using rabbit monoclonal antibodies(RabMAbs) against a hapten-protein conjugate of CPFX-bovine serum albumin(BSA).The indirect competitive ELISA of CPFX had a concentration at 50% inhibition(IC50) of 1.47 ng/ml and a limit of detection(LOD) of 0.095 ng/ml.The mAb exhibited some cross-reactivity,however,not so high with enrofloxacin(28.8%),ofloxacin(13.1%),norfloxacin(11.0%),fleroxacin(22.6%),and pefloxacin(20.4%).And it showed almost no cross-reactivity with other antibiotics or sulfonamides evaluated in this study.The competitive ELISA kit developed here could be used as a screening tool to detect and control illegal addition of CPFX in food products.This kit had been applied to milk detection and the recovery rates from samples spiked by CPFX were in a range of 63.02%-84.60%,with coefficients of variation of less than 12.2%.
文摘Since the approval of rituximab in 1997, monoclonal antibodies(mAbs) have become an increasingly important component of therapeutic regimens in oncology. The success of mAbs as a therapeutic class is a result of great strides that have been made in molecular biology and in biotechnology over the past several decades. Currently, there are 14 approved mAb products for oncology indications, and there are ten additional mAbs in late stages of clinical trials. Compared to traditional chemotherapeutic agents, mAbs have several advantages, including a long circulating half-life and high target specificity. Antibodies can serve as cytotoxic agents when administered alone, exerting a pharmacologic effect through several mechanisms involving the antigen binding(Fab) and/or Fc domains of the molecule, and mAbs may also be utilized as drug carriers, targeting a toxic payload to cancer cells. The extremely high affinity of mAbs for their targets, which is desirable with respect to pharmacodynamics(i.e., contributing to the high therapeutic selectivity of mAb), often leads to complex, non-linear, target-mediated pharmacokinetics. In this report, we summarize the pharmacokinetic and pharmacodynamics of mAbs that have been approved and of mAbs that are nearing approval for oncology indications, with particular focus on the molecular and cellular mechanisms responsible for their disposition and efficacy.
基金Supported by National Natural Science Fundation of China(Project No.2 9875 0 10 ) and the Health Department of JilinProvince(Project No.980 4 7) ,China
文摘Cardiac troponin I(cTnI) was separated and purified from human left ventricular tissue by affinity chromatographic method and used to immunize Balb/c mice by intraperitoneal injection and four hybridoma cell lines, which secreted monoclonal antibody(mAb) against human cTnI, were obtained by cell fusion, identification and cloning twice. Three mAbs(9F5, 2F11, 8C12) were produced from the ascites of Balb/c mice injected intraperitoneally the hybridoma cells and characterized by means of a surface plasmon resonance(SPR) biosensor. An optimal and specific sensing membrane for troponin I was prepared with staphylococcal protein A(SPA) as the intermediate layer and mAb against human cTnI as the capture antibody. On the basis of the sensing membrane, two modes of operation of the SPR biosensor were developed, i.e ., a direct detection of antigen antibody affinity and a sandwich assay. In the sandwich assay detection mode, the mAbs competition was measured by monitoring whether the secondary antibody had been attached to the cTnI already captured by the first antibody on the sensor surface. The SPR biosensor was shown to be able to directly detect the antigen antibody affinity and the order of the affinity was found to be 9F5>2F11>8C12. In the sandwich detection mode, it was found that the different epitopes on the cTnI molecules were recognized by the three mAbs respectively, but the asymmetrical competition was shown between 2F11 and 8C12 and no competition was found between 9F5 and 2F11 or 8c12. Based on these results, a double monoclonal sandwich immunoassay for cTnI was developed by using the optimal antibody pair of 9F5 and 2F11 and the SPR biosensor with SPA substrate membrane, which showed an excellent sensitivity of 0.8 μg/L for both the buffer and the serum samples compared with the direct detection of cTnI for the buffer with the lowest detection limit of 4 μg/L and conventional ELISA with the sensitivity of 1.9 μg/L.
