摘要
目的 探讨转染人细胞毒性T淋巴细胞相关抗原4免疫球蛋白（CTLA4Ig）基因的树突状细胞（DCsRev）对反应性T细胞的作用。方法 通过重组逆转录病毒将目的基因CTLA4Ig转染到大鼠骨髓来源的树突状细胞（DCs）中。采用逆转录聚合酶链反应（RT-PCR）和斑点酶联免疫吸附试验（Dot-ELISA）检测CTLA4Ig在DCs中的表达；采用混合淋巴细胞反应（MLR）检测DCsRev对反应性T细胞的作用。结果 检测结果证实CTLA4Ig基因成功转染至DCs。DCsRev的数量以及用DCsRev预处理反应性T细胞的时间长短与抑制MLR中T细胞增殖有一定的效应关系。当DCsRev数量在10^3～10^4。之间时，其抑制率最高，抑制率可达到为69．12％；用DCsRev预处理反应性T细胞12 h时，其对MLR中T细胞增殖的抑制率最高，为98．3％，12 h以后，随着预处理时间的延长，抑制率却不断下降。经DCsRev诱导的大鼠体内脾淋巴细胞在MLR中增殖低下。结论 转染CT-LA4Ig基因的DCs不但丧失了刺激MLR的能力，并且能够抑制MLR中反应性T细胞的增殖，提示DCsRev可能诱导抗原特异性T细胞的免疫耐受。
Objective To investigate the possibility of DCs transfected with CTLA4Ig cDNA by retrovirus vector to induce antigen specific hyporesponsiveness. Methods The modified DCs （CTLA4Ig-DCs） were prepared by transferring the DCs from cultured rat BM cells with the constructed retro-virus CTLA4Ig vector. The CTLA4Ig gene expression was detected on the prepared DCs by RT-PCR and Dot-ELISA methods. The influence of the modified DCs on mixed lymphocyte reaction （MLR） intensity was determined by T cell proliferation. Results The CTLA4Ig gene could be transferred successfully to DCs by retrovirus vector, which was confirmed by RT-PCR and Dot-ELISA methods. As compared with control group, DCsRev could significantly and antigen-specifically inhibit MLR in vitro in a dose- and time-dependent manner. The number of DCRev from 10^3 to 10^4 could reach the maximal inhibition by 69.12 %. On the other hand, the inhibition capacity of DCsRev was increased from 48 h to 12 h prior to adding stimulating cells and the maximal inhibition was 98. 3% at 12 h. Analysis of T cell proliferation revealed that donor-specific inhibition could be induced by DCsRev in an ex vivo model. But this kind of inhibition was not lifetime. Conclusions The CTLA4Ig gene could be transferred successfully to DCs by retrovirus vector. This kind of DCs lost capacity of stimulating MLR, and could inhibit T cell proliferation, which might be responsible for the antigen specific suppression induced by DCsRev.
出处
《中华器官移植杂志》
CAS
CSCD
北大核心
2006年第6期327-329,共3页
Chinese Journal of Organ Transplantation
关键词
转基因
树突细胞
T淋巴细胞
抑制效应
Transgenes
Dendritic cell
T-lymphocytes, suppressor-effector
