Establishment of Monoclonal Antibody Competitive ELISA Using Monoclonal Antibody Against VP1 Protein of Asia 1 Type Foot-and-Mouth Disease Virus

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.

Analysis of Specific Th1/Th2 Helper Cell Responses and IgG Subtype Antibodies in Anti-CD4 Monoclonal Antibody Treated Mice with Autoimmune Cardiomyopathy

The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice treated with anti-CD4 monoclonal antibody. Eighteen male BALB/c mice （6–8 weeks old） were randomized into 3 groups： dilated cardiomyopathy （DCM） group, DCM-tolerance （Tol） group and control group. The mice in DCM group were immunized with the peptides derived from human ADP/ATP carrier protein for 6 months and mice in the control group were sham-immunized, while the mice in DCM-Tol group were immunized with ADP/ATP carrier protein and anti-CD4 McAb simultaneously. Serum autoantibody against ADP/ATP carrier and IgG subclasses were measured by ELISA, intracellular cytokines IFN-γ and IL-4 of Th cells were moni- tored with flow cytometry, and splenic T cell cytokines IFN-γ, IL-2, IL-4 and IL-6 were detected by using real-time fluorescent quantitative PCR. The results showed that the autoantibody against ADP/ATP carrier was found in all mice in DCM group, and the antibody level, serum IgG1 and IgG2a subclasses, cytokines in T cells and Th cells were all elevated in DCM group, as compared with those in control group （P〈0.01）. On the other hand, in DCM-Tol group, the autoantibody level and contents of all the cytokines were significantly different from those in DCM group （P〈0.01）, and were close to those in control group. And the levels of IgG1, IgG2a, IgG2b and IgG3 were influenced, to varying degrees, by anti-CD4 McAb as compared with those in DCM group. All these four types of IgG subclasses were substantially decreased in DCM-Tol group as compared with DCM group. It is concluded that the treatment with anti-CD4 McAb could prevent the activation of T cells, reverse the abnormal secretion of cytokines and the imbalance between Th1/Th2 cell subsets and abnormal production of autoantibody against ADP/ATP carrier, and eventually avoid myocardial injuries.

Application of VP1 Protein to Develop Monoclonal Antibody against Foot-and-mouth Disease Virus Asia1 Type

In order to develop an anti-FMDV Asial type monoclonal antibody （mAb）, BABL/c mice were immunized with recombinant FMDV VP1 protein. Three mAbs, 1B8, 5El and 5E2, were then further optimized. The result indicated that prepared anti-FMDV Asial mAbs had no cross-reactivity with Swine vesicular disease （SVD） and FMDV O, A and C type antigen. Their titers in abdomen liquor were 1：5×10^6, 1：2×10^6 and 1：5×10^6, respectively. 1B8 was found to be of IgG1 subtype, 5El and 5E2 belonged to IgG2b subtype. In this study, the prepared mAbs are specific for detecting FMDV type Asia1, and is potentially useful for pen-side diagnosis.

Effects of monoclonal antibodies against human stathmin 1 combined paclitaxel on proliferation of human hepatocellular carcinoma cell lines

Objective： We investigated the effects of monoclonal antibodies against stathmin 1 combined paclitaxel on the proliferation of HCC cells. Methods： HepG2 cells were treated with monoclonal antibodies against stathmin 1, paclitaxel alone or their combination, with the untreated cells used as the control, 24, 48, 72, 96 h later, the cell growth condition was observed by invert microscope and inhabitation rate was studied by MTT assay; The apoptosis was analyzed by flow cytometry with Annexin V/PI. Results： The population decreased and shape, size changed after treating with different concentration of experimental groups. Monoclonal antibodies against stathmin 1 and paclitaxel used alone or in combination both inhibited the proliferation of HepG2 cells, the inhibition ratio of their combination was more higher （P 〈 0.05）, and a synergistic effect of the two agents was noted in their combined action （P 〈 0.05）. Combined treatment of the cells resulted in significantly higher apoptosis rate than that in the other groups （P 〈 0.05）. Conclusion： Monoclonal antibodies against stathmin 1 and paclitaxel used alone or in combination both can inhibit proliferation of HepG2 cells and induce apoptosis. A synergistic effect is obsewed between the monoclonal antibodies against stathmin 1 and paclitaxel in their inhibition of HepG2 cell proliferation.

Novel monoclonal antibody against beta 1 integrin enhances cisplatin efficacy in human lung adenocarcinoma cells

The use of anti-beta 1 integrin monoclonal antibody in lung cancer treatment has proven beneficial. Here, we developed a novel monoclonal antibody （mAb）, called P5, by immunizing mice with human peripheral blood mononuclear cells （PBMC）. Its anti-tumor effect is now being tested, in a clinical phase Ⅲ trial, in combinato- rial treatments with various chemical drugs. To confirm that P5 indeed binds to beta 1 integrin, cell lysates were immunoprecipitated with commercial anti-beta 1 integrin mAb （TS2/16） and immunoblotted against P5 to reveal a 140 kDa molecular weight band, as expected. Immunoprecipitation with P5 followed by LC/MS protein sequence analysis further verified P5 antigen to be beta 1 integrin. Cisplatin treatment upregulated cell surface expression of beta 1 integrin in A549 cells, while causing inhibition of cell growth. When cells were co-treated with different concentrations of P5 mAb, the cisplatin-mediated inhibitory effect was enhanced in a dose-dependent manner. Our findings show that a combinatorial treatment of P5 mAb and cisplatin in A549 cells resulted in a 30% increase in apoptosis, compared to baseline, and significantly more when compared to either the cisplatin or P5 alone group. The entire peptide sequences in CDR from variable region of Ig heavy and light chain gene for P5 mAb are also disclosed. Together, these results provide evidence of the beneficial effect of P5 mAb in combinatorial treatment of human lung adenocarcinoma.

Induction of specific immunosuppression of cardiac allograft rejection withmonoclonal antibodies to CD44, LFA-1 and ICAM-1

Objective:To evaluate the immunosuppressive effect of monoclonal antibodies (McAb) against cell surface adhesion molecules on transplant rejection. Methods: C57BL/6 (H-2b) mouse cardiac grafts were transplanted into BALB/c(H- 2d) mice. This model was used to investigate the possibility of immunosuppressive induction with CD44 McAb, leukocyte function associated antigen (LFA-1) and intercellular adhesion molecule (ICAM-1). Results: Treatment of the allograft recipients with CD44 McAb alone, or both LFA-1 and ICAM-1 or combination of these 3 McAb significantly prolonged the cardiac allografts survival as compared with PBS controls (P<0.01). The combination of anti-CD44 and ICAM-1 and LFA-1 McAb was shown to produce more significant prolongation of grafts survival than anti-CD44 McAb alone or both anti-ICAM- 1 and LFA-1 McAb (P < 0.01). Histological examination of the grafts treated with the McAb displayed greatly reduced mononuclear cell infiltration. The proliferation of spleen cells from recipient BALB/c with McAb treatment was significantly inhibited in response to the stimulators of C57BL/6 spleen cells, but increased upon the stimulation of C3H/He (H-2k) spleen cells, as demonstrated by mixed lymphocyte reaction. Similarly, the cytotoxic activity against donor H-2-compatible (H-2b) target cells, EL-4 cells, was significantly suppressed. The spleen cells from allografted recipient BALB/c mice with McAb treatment induced specific tolerance for C57BL/6 cardiac grafts in allografted recipients, whereas those from allografted BALB/c mice without McAb treatment induced acute rejection. Conclusion: These results indicate that antiadhesion therapy using a combination of McAb to adhesion molecules can induce specific immunosuppression of transplant rejection.

Preparation and Characterization of Monoclonal Antibodies against VP1 Protein of Foot-and-mouth Disease Virus O/China99

Monoclonal antibodies (McAbs) 1A9 and 9F12 against Foot-and-mouth disease virus (FMDV) serotype O were produced by fusing SP2/0 myeloma cells with splenocyte from the mouse immunized with O/China99. Both McAbs reacted with O/China99 but not with Asia 1, as determined by immunohistochemistry assay. The microneutralization titer of the McAbs 1A9 and 9F12 were 640 and 1 280, respectively. Both McAbs contain kappa light chains, but the McAbs 1A9 and 9F12 were IgG1 and IgM, respectively. In order to define the McAbs binding epitopes, the reactivity of these McAbs against VP1, P20 and P14 were examined using indirect ELISA, the result showed that both McAbs reacted with VP1 and P20. McAbs may be used for further studies of vaccine, diagnostic methods, prophylaxis, etiological and immunological researches on FMDV.

Effects of anti-CXCR_4 monoclonal antibody 12G5 on proliferation and apoptosis of human acute myelocytic leukemia cell line HL-60

Objective：To investigate the expression of CXCR4 on HL-60 cell line and the proliferation, apoptosis of HL-60 cell line cocultured with bone marrow stromal cells, so as to assess the possibility of 12G5, an anti-CXCR4 monoclonal antibody, in eradicating the minimal residual disease. Methods：The activity of SDF-1 was inhibited by 10 μg/ml 12G5. After treatment with 12G5, the status of adhesion was observed, and the adhesion rates, apoptosis and cell cycles were detected after 24 h of treatment. Cell growth rates were measured by trypan blue exclusion. Cell growth curve was plotted, and the expression of PCNA and apoptosis related protein including PCNA, Bcl-2 and Fas were detected with immunohistochemical technique. Results：（1） There was middling degree expression of CXCR4 on HL-B0 membrane. From 0 h to 6 h, as the time of 12G5 incubation along, the expression of CXCR4 decreased gradually. （2） After treatment for 24 h, the adhesion rates in the experiment group and the control were （39.4±7.9）% and （51.4±5.9）%, respectively. （3）After treatment for 24 h, the percentage of HL-60 cells in G0/G1 phase were （55.21±4.9）%, and that in S phase and G2/M phase were （30.40±4.1）% and （14.39± 5.2）%, respectively, with the corresponding proportions being （44. 67±2.2）%, （45.30±3.7）%, and （10. 03±2.6）% in the control. （4） The percentage of apoptotic HL-60 cells was （8.95±1.7）% in the experiment group, compared to （3. 97±2. 4）% in the control. （5）The survival rates of HL-60 cells decreased markedly at 48 h to 96 h, and the proliferation slowed down at this time duration. （6）The expression of PCNA and Bcl-2 down-regulated significantly, but the Fas protein expression was up-regulated. Conclusion：12G5 could inhibit the capability of adhesion and proliferation of HL-60 cells and it can induce more cells to enter G0/G1 phase and promote apoptosis. It may be helpful by inhibiting the bioactivity of SDF-1 with 12G5 in the therapy of marrow residual disease.

PD-1单抗后线辅助治疗晚期结直肠癌患者对胃肠功能、肿瘤标志物的影响

目的分析程序性死亡受体-1(PD-1)单抗后线辅助治疗晚期结直肠癌患者对胃肠功能、肿瘤标志物的影响。方法前瞻性选取2020年1月至2023年1月海口市人民医院收治的105例晚期结直肠癌患者为研究对象,按照随机数字表法将患者分为对照组(n=50)、研究组(n=55)。对照组采用阿帕替尼治疗,研究组在对照组的基础上联合PD-1单抗后线治疗,3周为1个疗程,共治疗4个疗程。比较两组的临床疗效、胃肠功能改善时间,治疗前、治疗12周后的肿瘤标志物[癌胚抗原、糖类抗原(CA)72-4、CA199]、免疫功能(CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))指标以及不良反应发生情况。结果治疗12周后,研究组的客观缓解率(ORR)、病情控制率(DCR)分别为78.33%、90.91%,均高于对照组(58.00%、70.00%),差异均有统计学意义(P<0.05)。研究组患者的首次排便时间、首次排气时间、肠鸣音消退时间分别为(51.50±5.02)、(35.52±4.25)、(44.28±4.80)d,均短于对照组[(69.37±6.40)、(50.63±5.10)、(53.50±6.15)d],差异均有统计学意义(P<0.05)。治疗12周后,研究组癌胚抗原、CA72-4、CA199水平分别为(12.57±1.64)ng/mL、(17.60±3.45)U/mL、(58.29±8.70)kU/L,均低于对照组[(17.24±2.50)ng/mL、(27.59±4.67)U/mL、(82.65±12.29)kU/L],差异均有统计学意义(P<0.05)。治疗12周后,研究组CD4^(+)、CD4^(+)/CD8^(+)水平分别为(21.42±3.54)%、0.73±0.30,均低于对照组[(28.39±4.38)%、1.12±0.41],CD8^(+)水平为(30.36±4.52)%,高于对照组[(25.71±3.30)%],差异均有统计学意义(P<0.05)。研究组的不良反应发生率为9.09%,稍低于对照组(16.00%),但两组比较差异无统计学意义(P>0.05)。结论通过PD-1单抗后线辅助治疗可有效改善晚期结直肠癌患者的临床疗效,效果明显,改善胃肠功能,降低肿瘤标志物指标水平,调节机体免疫功能,可为临床干预此病提供参考。

口蹄疫病毒Asia1型猪源中和抗体的筛选与抗原表位鉴定

Asia1型口蹄疫病毒(FMDV)仍然在我国周边国家存在,对我国畜牧业造成长期威胁。本研究旨在利用单个B细胞抗体技术研制Asia1型FMDV的中和性单克隆抗体,以此为工具,鉴定Asia1型FMDV的保护性抗原位点。以FMDV Asia1/JS/05为诱饵抗原,通过流式细胞术分选免疫猪PBMCs中的抗原特异性B细胞,通过巢式PCR扩增单个B细胞IgG抗体重链与轻链可变区基因序列,分别构建IgG抗体重链与轻链表达质粒,将其共转染CHO-S细胞进行抗体表达;通过间接ELISA、间接免疫荧光试验(IFA)、病毒中和试验(VNT)验证抗体反应性和中和活性,利用免疫印迹、中和抗体逃逸突变株筛选鉴定中和抗体所识别的抗原表位类型和抗原表位关键氨基酸。结果显示:获得了5株反应性良好的Asia1型FMDV特异性抗体,其中PD3和PD7为中和抗体,两株中和抗体识别相同表位,关键氨基酸为VP2蛋白72位残基(D)。本研究首次获得Asia1型FMDV特异性猪源中和抗体,鉴定VP272D是中和表位的关键氨基酸,进一步丰富了Asia1型FMDV抗原位点信息,为FMDV Asia1型分子疫苗和新诊断检测技术研究的奠定了基础。

犬PD-1单克隆抗体的筛选与鉴定

为筛选犬程序性死亡受体1(cPD-1)单克隆抗体,以原核表达并纯化复性的cPD-1胞外区蛋白为靶抗原免疫BALB/c小鼠,应用单克隆抗体杂交瘤细胞技术和间接ELISA方法,经3轮轮筛选和克隆化,获得1株能稳定分泌抗cPD-1单克隆抗体的杂交瘤细胞株1F9。间接ELISA检测显示1F9杂交瘤细胞株连续传代培养能稳定分泌单克隆抗体,效价达到1∶2048,亚型鉴定重链为IgG1,轻链为κ;以HEK293细胞表达cPD-1胞外区蛋白为检测抗原,Western-blot和间接免疫荧光试验进行鉴定,结果显示1F9单克隆抗体能特异性结合cPD-1胞外区蛋白。本研究通过小鼠杂交瘤技术成功筛选到1株鼠源cPD-1单克隆抗体。

PD-1单抗治疗一例dMMR/MSI-H/TMB-H型结肠癌伴颅内转移瘤患者临床完全缓解

一例70岁男性患者,在接受右半肠癌根治性手术1年后出现了记忆丧失和认知功能下降的症状,头颅磁共振成像检查发现脑部肿块,手术后经病理检查确诊为结肠腺癌转移。原发灶及颅内转移瘤免疫组织化学检测均提示为错配修复缺陷。原发结肠肿瘤组织基因检测证实为微卫星高度不稳定伴有高肿瘤突变负荷,肿瘤突变负荷为77.7 muts/Mb。患者结肠癌根治术和颅内转移瘤术后均接受了辅助化疗,但在颅内转移瘤切除术和化疗结束后1个月颅内转移复发。患者接受帕博利珠单抗治疗后结果颅内转移瘤消退并达到临床完全缓解。

血清IL-17、INF-γ水平与肝细胞癌患者PD-1单抗治疗效果的关系

目的探究血清IL-17、INF-γ水平与肝细胞癌患者PD-1单抗治疗效果的关系。方法选取2023年1月至2023年8月收治的60例肝细胞癌患者作为研究对象,均接受PD-1单抗治疗。比较观察治疗有效患者与无效患者IL-17、INF-γ水平情况,IL-17、INF-γ水平与肝癌细胞患者各临床特征的关系,ROC曲线分析IL-17、INF-γ表达水平对肝癌细胞患者PD-1单抗治疗效果的预测价值关系。结果治疗有效组患者IL-17水平(14.17±2.08)pg/ml低于治疗无效组的(21.28±3.69)pg/ml,INF-γ(37.45±4.52)pg/ml高于对照组的(22.36±3.27)pg/ml(P<0.05)。在临床分期、肝外转移、血管侵犯等方面,分期越高、有肝外转移、有血管侵犯患者的IL-17水平高于分期越低、无肝转移、无血管侵犯患者(P<0.05)。分期越高、有肝外转移、有血管侵犯患者的INF-γ水平低于分期越低、无肝外转移、无血管侵犯患者(P<0.05)。通过ROC曲线的绘制可以得出:(1)IL-17、INF-γ的曲线下面积分别是0.753、0.764,均具有良好的诊断效能,但与2项联合相比,2项联合的曲线下面积0.877均高于各单一指标的曲线下面积(P<0.05);(2)IL-17、INF-γ的cut-off值是6.21 pg/ml、36.52 pg/ml;(3)2项联合的灵敏度(0.935)、特异度(0.952)均明显高于IL-17的(0.552、0.801)和INF-γ的(0.457、0.824)(P<0.05)。结论血清IL-17、INF-γ水平可对细胞癌患者PD-1单抗治疗效果进行预测评估,且两者联合预测的效能更高,具有显著的临床应用价值。

IMpower210:A phase Ⅲ study of second-line atezolizumab vs. docetaxel in East Asian patients with non-small cell lung cancer

Objective: IMpower210(NCT02813785) explored the efficacy and safety of single-agent atezolizumab vs.docetaxel as second-line treatment for advanced non-small cell lung cancer(NSCLC) in East Asian patients.Methods: Key eligibility criteria for this phase Ⅲ, open-label, randomized study included age ≥18 years;histologically documented advanced NSCLC per the Union for International Cancer Control/American Joint Committee on Cancer staging system(7th edition);Eastern Cooperative Oncology Group performance status of 0 or 1;and disease progression following platinum-based chemotherapy for advanced or metastatic NSCLC. Patients were randomized 2:1 to receive either atezolizumab(1,200 mg) or docetaxel(75 mg/m^(2)). The primary study endpoint was overall survival(OS) in the intention-to-treat(ITT) population with wild-type epidermal growth factor receptor expression(ITT EGFR-WT) and in the overall ITT population.Results: Median OS in the ITT EGFR-WT population(n=467) was 12.3 [95% confidence interval(95% CI),10.3-13.8] months in the atezolizumab arm(n=312) and 9.9(95% CI, 7.8-13.9) months in the docetaxel arm[n=155;stratified hazard ratio(HR), 0.82;95% CI, 0.66-1.03]. Median OS in the overall ITT population was 12.5(95% CI, 10.8-13.8) months with atezolizumab treatment and 11.1(95% CI, 8.4-14.2) months(n=377) with docetaxel treatment(n=188;stratified HR, 0.87;95% CI, 0.71-1.08). Grade 3/4 treatment-related adverse events(TRAEs) occurred in 18.4% of patients in the atezolizumab arm and 50.0% of patients in the docetaxel arm.Conclusions: IMpower210 did not meet its primary efficacy endpoint of OS in the ITT EGFR-WT or overall ITT populations. Atezolizumab was comparatively more tolerable than docetaxel, with a lower incidence of grade3/4 TRAEs.

Safety of teplizumab in patients with high-risk for diabetes mellitus type 1:A systematic review

BACKGROUND The incidence of diabetes mellitus type 1(DM1)has been rising worldwide because of improvements in diagnostic techniques and improved access to care in countries with lower socioeconomic status.A new anti-CD4 antibody,Teplizumab,has been shown to delay the progression of DM1 and is the only medication approved for this indication.However,more information is needed about the safety profile of this drug.AIM To identify the odds ratios(OR)of systems-based adverse effects for Teplizumab when compared to Placebo.METHODS An extensive systematic review was conducted from the inception of the medication until December 31,2023.All clinical trials and studies that evaluated Teplizumab vs placebo were included in the initial review.The study protocol was designed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines guidelines and was registered in PROSPERO(ID:CRD42024496169).Crude OR were generated using RevMan Software version 5.4.RESULTS After screening and review,5 studies were selected to determine the risk of adverse effects of teplizumab compared to placebo.A total of 561 patients were included in the study population.Total adverse effects and system-based adverse effects were studied and reported.We determined that patients receiving Teplizumab had a higher risk of developing gastrointestinal(GI)(OR=1.60,95%CI:1.01-2.52,P=0.04),dermatological(OR=6.33,95%CI:4.05-9.88,P<0.00001)and hematological adverse effects(OR=19.03,95%CI:11.09-32.66,P<0.00001).These patients were also significantly likely to have active Epstein-Barr Virus infection(OR=3.16,95%CI:1.51-6.64,P<0.002).While our data showed that patients receiving Teplizumab did have a higher incidence of total adverse effects vs placebo,this finding did not reach statistical significance(OR=2.25,95%CI:0.80-6.29,P=0.12).CONCLUSION Our systematic review suggests that Teplizumab patients are at risk for significant adverse effects,primarily related to GI,dermatological,and hematological systems.The total adverse effect data is limited as study populations are small.More studies should be conducted on this medication to better inform the target population of potential adverse effects.

Evaluation of teplizumab's efficacy and safety in treatment of type 1 diabetes mellitus:A systematic review and meta-analysis

BACKGROUND Islets of Langerhans beta cells diminish in autoimmune type 1 diabetes mellitus(T1DM).Teplizumab,a humanized anti-CD3 monoclonal antibody,may help T1DM.Its long-term implications on clinical T1DM development,safety,and efficacy are unknown.AIM To assess the effectiveness and safety of teplizumab as a therapeutic intervention for individuals with T1DM.METHODS A systematic search was conducted using four electronic databases(PubMed,Embase,Scopus,and Cochrane Library)to select publications published in peerreviewed journals written in English.The odds ratio(OR)and risk ratio(RR)were calculated,along with their 95%CI.We assessed heterogeneity using Cochrane Q and I2 statistics and the appropriate P value.RESULTS There were 8 randomized controlled trials(RCTs)in the current meta-analysis with a total of 1908 T1DM patients from diverse age cohorts,with 1361 patients receiving Teplizumab and 547 patients receiving a placebo.Teplizumab was found to have a substantial link with a decrease in insulin consumption,with an OR of 4.13(95%CI:1.72 to 9.90).Teplizumab is associated with an improved Cpeptide response(OR 2.49;95%CI:1.62 to 3.81)and a significant change in Glycated haemoglobin A1c(HbA1c)levels in people with type 1 diabetes[OR 1.75(95%CI:1.03 to 2.98)],and it has a RR of 0.71(95%CI:0.53 to 0.95).CONCLUSION In type 1 diabetics,teplizumab decreased insulin consumption,improved C-peptide response,and significantly changed HbA1c levels with negligible side effects.Teplizumab appears to improve glycaemic control and diabetes management with good safety and efficacy.

靶向PD-1/PD-L1蛋白-蛋白相互作用小分子抑制剂研究进展

目的:阐述PD-1/PD-L1的相互作用机制及其在癌细胞免疫逃逸上的作用,并介绍近几年开发的靶向PD-1/PD-L1的新型小分子抑制剂。方法:检索国内外PD-1/PD-L1抑制剂的文献,整理和比较近几年开发的靶向PD-1/PD-L1的小分子抑制剂。结果:PD-1/PD-L1抑制剂主要包括单克降抗体、拟肽抑制剂和小分子抑制剂,主要通过阻断PD-1/PD-L相互作用,形成PD-L1二聚体发挥作用。意义:开发靶向PD-1/PD-L1的小分子药物是一个具有挑战性的过程,小分子抑制剂具有比抗体更好的抑制肿瘤生长和迁移的能力,近几年小分子抑制剂的设计思路为小分子抑制剂的设计提供了新的思路。

PD-1单抗联合顺铂或吉西他滨化疗对KRAS突变非小细胞肺癌A549细胞移植瘤小鼠模型的治疗作用

目的:探讨程序性死亡受体-1(PD-1)单抗联合顺铂或吉西他滨在KRAS基因突变非小细胞肺癌(NSCLC)A549细胞移植瘤小鼠模型治疗中的作用。方法:构建免疫系统-肿瘤双人源化A549细胞小鼠移植瘤模型,将60只小鼠按随机数字表法分成6组(10只/组),分别为对照组(200μL/kg PBS)、PD-1单抗组(20 mg/kg PD-1单抗)、顺铂组(3 mg/kg顺铂)、PD-1单抗+顺铂组(20 mg/kg PD-1单抗+3 mg/kg顺铂)、吉西他滨组(30 mg/kg吉西他滨)和PD-1单抗+吉西他滨组(20 mg/kg PD-1单抗+30 mg/kg吉西他滨)。TUNEL和DAPI双染色法检测移植瘤组织中细胞凋亡水平,测量移植瘤体积和质量并计算肿瘤生长抑制率,免疫组化法检测移植瘤微血管密度(MVD)。结果:成功构建免疫系统-肿瘤双人源化NSCLC A549细胞小鼠移植瘤模型,PD-1单抗+顺铂组移植瘤的细胞凋亡率、肿瘤生长抑制率均最高,移植瘤体积、质量和MVD均最小,与其他5组小鼠比较差异均有统计学意义(均P<0.05)。结论:顺铂与PD-1单抗具有协同活性,而吉西他滨拮抗PD-1单抗的治疗作用。提示PD-1单抗联合顺铂对KRAS突变NSCLC A549细胞移植瘤小鼠的疗效更好。

Combination of specific monoclonal antibodies allow identification of soluble aggregates of by sandwich ELISA

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.