目的:构建携带小鼠MHCII类分子反式激活因子(MHC class II molecule transactivator,CIITA)突变体基因的腺病毒,并观察腺病毒介导该基因的表达情况以及表达产物的体外功能。方法:采用常规分子生物学方法从IFN-γ诱导后的BALB/c小鼠腹腔...目的:构建携带小鼠MHCII类分子反式激活因子(MHC class II molecule transactivator,CIITA)突变体基因的腺病毒,并观察腺病毒介导该基因的表达情况以及表达产物的体外功能。方法:采用常规分子生物学方法从IFN-γ诱导后的BALB/c小鼠腹腔巨噬细胞中获得IV型CIITA cDNA;利用重叠延伸PCR法构建CIITA突变体基因,并克隆入表达载体pIRES;采用pAdEasy-1系统获得具有感染能力的、携带CIITA突变体基因的缺陷型重组腺病毒(Ad-CIITAm)和空载对照病毒(Ad-GFP),并经大量扩增、纯化及滴度测定;将Ad-CIITAm和Ad-GFP分别感染HeLa细胞和Raji细胞,流式细胞术观察对诱导型和组成型HLA-DR分子表达的影响。结果:成功克隆了小鼠CIITA突变体基因,并构建了携带小鼠CIITA突变体基因的重组腺病毒Ad-CIITAm;经流式细胞术证实感染Ad-CIITAm的Hela和Raji细胞较感染Ad-GFP的细胞,其表面HLA-DR分子的表达均受到明显的抑制。结论:本实验证实了重组腺病毒介导表达的小鼠CIITA突变体在体外能够有效地抑制MHCII类分子的表达。展开更多
评估IFN-γ调控型启动子(CIITA-pIV)驱动的MHC II类分子反式激活因子突变体(MHC class II transactivator mu-tant,CIITAm)重组腺病毒Ad-pIV-CIITAm对小鼠实验性自身免疫性甲状腺炎(experimental autoimmune thyroiditis,EAT)的治疗效果...评估IFN-γ调控型启动子(CIITA-pIV)驱动的MHC II类分子反式激活因子突变体(MHC class II transactivator mu-tant,CIITAm)重组腺病毒Ad-pIV-CIITAm对小鼠实验性自身免疫性甲状腺炎(experimental autoimmune thyroiditis,EAT)的治疗效果,并探讨其可能的作用机制。34只健康雌性CBA/J小鼠随机分成CIITAm治疗组(n=9)、GFP对照组(n=9)、EAT模型组(n=8)和正常对照组(n=8)共四组。正常对照组不做特殊处理,其余三组均以猪甲状腺球蛋白(porcinethyroglobulin,pTg)+弗氏佐剂(complete or incomplete Freund adjuvant,CFA/IFA)建立EAT小鼠模型,并分别静脉注射重组腺病毒Ad-pIV-CIITAm、Ad-GFP及等体积生理盐水。首次免疫后第29天处死小鼠,进行H-E染色观察甲状腺病理形态;免疫组织化学染色测定甲状腺MHC II类分子表达;分析pTg刺激下脾脏淋巴细胞的增殖及其上清液中IFN-γ的分泌水平;ELISA法检测血浆中抗-pTg自身抗体滴度;流式细胞术分析外周血和脾脏淋巴细胞中T细胞亚群。结果:H-E染色结果表明,CIITAm治疗组甲状腺淋巴细胞浸润指数(0.5±0.5)低于GFP对照组(1.5±0.2)和EAT模型组(1.4±0.4,P<0.01)。免疫组化结果显示,GFP对照组和EAT模型组甲状腺组织有弥漫性MHC II类分子表达,而CIITAm治疗组未见明显表达,正常对照组表达呈阴性。80μg/ml pTg刺激下,CIITAm治疗组小鼠淋巴细胞刺激指数(SI)明显低于GFP对照组或EAT模型组(P<0.01);培养上清各组IFN-γ分泌水平结果类似(P<0.01)。CIITAm治疗组血浆抗-pTg自身抗体滴度显著低于GFP对照组或EAT模型组(P<0.05);CIITAm治疗组外周血和脾脏CD4+T细胞百分率亦显著低于GFP对照组或EAT模型组(P<0.05)。重组腺病毒Ad-pIV-CIITAm能抑制EAT小鼠甲状腺组织MHC II类分子表达,抑制自身反应性T细胞增殖,减轻甲状腺炎性细胞浸润,降低自身抗体滴度,对EAT有一定的治疗作用。展开更多
Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to stu...Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to study the role of two molecules during S.aureus infection.However,the contribution of HLA DP to S.aureus infection is unknown yet.Methods:In this study,we have produced HLA DP401 and HLA DRA0101 humanized mice by microinjection of C57BL/6J zygotes.Neo-floxed IAβ+/-mice were crossbred with Ella-Cre and further crossbred with HLA DP401 or HLA-DRA0101 humanized mice.After several rounds of traditional crossbreeding,we finally obtained HLA DP401-IAβ-/-and HLA DRA-IAβ-/-humanized mice,in which human DP401 or DRA0101 molecule was introduced into IAβ-/-mice deficient in endogenous murine MHC classⅡmolecules.A transnasal infection murine model of S.aureus pneumonia was induced in the humanized mice by administering 2×108CFU of S.aureus Newman dropwise into the nasal cavity.The immune responses and histopathology changes were further assessed in lungs in these infected mice.Results:We evaluated the local and systemic effects of S.aureus delivered intranasally in HLA DP401-IAβ-/-and HLA DRA-IAβ-/-transgenic mice.S.aureus Newman infection significantly increased the m RNA level of IL 12p40 in lungs in humanized mice.An increase in IFN-γand IL-6 protein was observed in HLA DRA-IAβ-/-mice.We observed a declining trend in the percentage of F4/80+macrophages in lungs in HLA DP401-IAβ-/-mice and a decreasing ratio of CD4+to CD8+T cells in lungs in IAβ-/-mice and HLA DP401-IAβ-/-mice.A decreasing ratio of Vβ3+to Vβ8+T cells was also found in the lymph node of IAβ-/-mice and HLA DP401-IAβ-/-mice.S.aureus Newman infection resulted in a weaker pathological injury in lungs in IAβ-/-genetic background mice.Conclusion:These humanized mice will be an invaluable mouse model to resolve the pathological mechanism of S.aureus pneumonia and study what role DP molecule plays in S.aureus infection.展开更多
[ Objective] To prepare the monoclonal antibody against chicken major histocompatibility complex class II molecules （MHC II）. [ Method ] The prokaryotic expression of the gene fragments of exons 2 -6 encoding alpha ...[ Objective] To prepare the monoclonal antibody against chicken major histocompatibility complex class II molecules （MHC II）. [ Method ] The prokaryotic expression of the gene fragments of exons 2 -6 encoding alpha chain of MHC II and exons 3 -6 encoding beta chain of MHC II were performed based on its protein sequences. After BALB/c mice were immunized with the purified fusion proteins, the mouse spleen cells were fused with mouse myeloma cells SP2/0. Then the positive hybridoma cells were screened and detected by indirect enzyme-linked immunosorbent assay （ELISA）. [ Result] One hybridoma cell strain secreting monoclonal antibody against alpha chain and two strains secreting monoclonal antibody against beta chain were obtained. These three hybridoma cell strains were named as MHC II alpha-4, MHC II betas-2 and MCH II betas-31, respectively. Their titers of ascites in indirect ELISA were 1 ： 256 000, 1 ： 256 000 and 1 ： 1 280 000, respectively. These antibodies could specifically recog- nize MHC II alpha chain or beta chain in western blotting. [ Conclusion] Three obtained hybridoma stains can stably produce the monoclonal antibody against chicken MHC class II molecules.展开更多
In daily life,we are frequently attacked by infection organisms such as bacteria and viruses. Major Histocompatibility (MHC) molecules have an essential role in T-cell activation and initiating an adaptive immune resp...In daily life,we are frequently attacked by infection organisms such as bacteria and viruses. Major Histocompatibility (MHC) molecules have an essential role in T-cell activation and initiating an adaptive immune response. Development of methods for prediction of MHC-Peptide binding is important in vaccine design and immunotherapy. In this study, we try to predict the binding between peptides and MHC class II. Support vector machine (SVM) and Multi-Layer Percep-tron (MLP) are used for classification. These classifiers based on pseudo amino acid compositions of data that we ex-tracted from PseAAC server, classify the data. Since, the dataset, used in this work, is imbalanced, we apply a pre-processing step to over-sample the minority class and come over this problem. The results show that using the concept of pseudo amino acid composition and applying over-sampling method, increases the performance of predictor. Fur-thermore, the results demonstrate that using the concept of PseAAC and SVM is a successful method for the prediction of MHC class II molecules.展开更多
文摘目的:构建携带小鼠MHCII类分子反式激活因子(MHC class II molecule transactivator,CIITA)突变体基因的腺病毒,并观察腺病毒介导该基因的表达情况以及表达产物的体外功能。方法:采用常规分子生物学方法从IFN-γ诱导后的BALB/c小鼠腹腔巨噬细胞中获得IV型CIITA cDNA;利用重叠延伸PCR法构建CIITA突变体基因,并克隆入表达载体pIRES;采用pAdEasy-1系统获得具有感染能力的、携带CIITA突变体基因的缺陷型重组腺病毒(Ad-CIITAm)和空载对照病毒(Ad-GFP),并经大量扩增、纯化及滴度测定;将Ad-CIITAm和Ad-GFP分别感染HeLa细胞和Raji细胞,流式细胞术观察对诱导型和组成型HLA-DR分子表达的影响。结果:成功克隆了小鼠CIITA突变体基因,并构建了携带小鼠CIITA突变体基因的重组腺病毒Ad-CIITAm;经流式细胞术证实感染Ad-CIITAm的Hela和Raji细胞较感染Ad-GFP的细胞,其表面HLA-DR分子的表达均受到明显的抑制。结论:本实验证实了重组腺病毒介导表达的小鼠CIITA突变体在体外能够有效地抑制MHCII类分子的表达。
基金National Science and Technology Major Project,Grant/Award Number:2016YFD0500208,2017ZX10304402-001-012 and 2017ZX10304402-001-006Shanghai Science and Technology Commission“R&D public service platform and institutional capacity improvement project”,Grant/Award Number:21DZ2291300Shanghai Public Health Clinical Center projects,Grant/Award Number:KY-GW-2021-39,KY-GW-2019-19 and KY-GW-2019-11。
文摘Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to study the role of two molecules during S.aureus infection.However,the contribution of HLA DP to S.aureus infection is unknown yet.Methods:In this study,we have produced HLA DP401 and HLA DRA0101 humanized mice by microinjection of C57BL/6J zygotes.Neo-floxed IAβ+/-mice were crossbred with Ella-Cre and further crossbred with HLA DP401 or HLA-DRA0101 humanized mice.After several rounds of traditional crossbreeding,we finally obtained HLA DP401-IAβ-/-and HLA DRA-IAβ-/-humanized mice,in which human DP401 or DRA0101 molecule was introduced into IAβ-/-mice deficient in endogenous murine MHC classⅡmolecules.A transnasal infection murine model of S.aureus pneumonia was induced in the humanized mice by administering 2×108CFU of S.aureus Newman dropwise into the nasal cavity.The immune responses and histopathology changes were further assessed in lungs in these infected mice.Results:We evaluated the local and systemic effects of S.aureus delivered intranasally in HLA DP401-IAβ-/-and HLA DRA-IAβ-/-transgenic mice.S.aureus Newman infection significantly increased the m RNA level of IL 12p40 in lungs in humanized mice.An increase in IFN-γand IL-6 protein was observed in HLA DRA-IAβ-/-mice.We observed a declining trend in the percentage of F4/80+macrophages in lungs in HLA DP401-IAβ-/-mice and a decreasing ratio of CD4+to CD8+T cells in lungs in IAβ-/-mice and HLA DP401-IAβ-/-mice.A decreasing ratio of Vβ3+to Vβ8+T cells was also found in the lymph node of IAβ-/-mice and HLA DP401-IAβ-/-mice.S.aureus Newman infection resulted in a weaker pathological injury in lungs in IAβ-/-genetic background mice.Conclusion:These humanized mice will be an invaluable mouse model to resolve the pathological mechanism of S.aureus pneumonia and study what role DP molecule plays in S.aureus infection.
基金supported by the National Natural Science Foundation (30671537)
文摘[ Objective] To prepare the monoclonal antibody against chicken major histocompatibility complex class II molecules （MHC II）. [ Method ] The prokaryotic expression of the gene fragments of exons 2 -6 encoding alpha chain of MHC II and exons 3 -6 encoding beta chain of MHC II were performed based on its protein sequences. After BALB/c mice were immunized with the purified fusion proteins, the mouse spleen cells were fused with mouse myeloma cells SP2/0. Then the positive hybridoma cells were screened and detected by indirect enzyme-linked immunosorbent assay （ELISA）. [ Result] One hybridoma cell strain secreting monoclonal antibody against alpha chain and two strains secreting monoclonal antibody against beta chain were obtained. These three hybridoma cell strains were named as MHC II alpha-4, MHC II betas-2 and MCH II betas-31, respectively. Their titers of ascites in indirect ELISA were 1 ： 256 000, 1 ： 256 000 and 1 ： 1 280 000, respectively. These antibodies could specifically recog- nize MHC II alpha chain or beta chain in western blotting. [ Conclusion] Three obtained hybridoma stains can stably produce the monoclonal antibody against chicken MHC class II molecules.
文摘In daily life,we are frequently attacked by infection organisms such as bacteria and viruses. Major Histocompatibility (MHC) molecules have an essential role in T-cell activation and initiating an adaptive immune response. Development of methods for prediction of MHC-Peptide binding is important in vaccine design and immunotherapy. In this study, we try to predict the binding between peptides and MHC class II. Support vector machine (SVM) and Multi-Layer Percep-tron (MLP) are used for classification. These classifiers based on pseudo amino acid compositions of data that we ex-tracted from PseAAC server, classify the data. Since, the dataset, used in this work, is imbalanced, we apply a pre-processing step to over-sample the minority class and come over this problem. The results show that using the concept of pseudo amino acid composition and applying over-sampling method, increases the performance of predictor. Fur-thermore, the results demonstrate that using the concept of PseAAC and SVM is a successful method for the prediction of MHC class II molecules.
