中文摘要：

目的探讨阻断BTLA-HVEM（B／T淋巴细胞弱化因子．疱疹病毒进入介质）通路对树突状细胞功能的影响和相关免疫学机制。方法构建小鼠BTLA胞外功能区的真核表达载体psBTLA，转染CHO细胞；HSP70-TC-1肿瘤抗原肽刺激小鼠骨髓来源DCs，流式细胞仪检测处理后DCs表面BTLA、HVEM的表达，同时给予转染了psBTLA质粒的CHO细胞的培养上清处理后，检测DCs表面B7-1的表达，ELISA检测上清中IL-12的分泌；处理后的DCs刺激脾细胞，检测淋巴细胞增殖和细胞因子分泌；检测psBTLA体内转染对宫颈癌细胞系TC-1成瘤小鼠DCs表达B7—1和肿瘤生长的影响。结果成功构建小鼠BTLA胞外段的真核表达载体psBTLA，获得了稳定转染psBTLA的CHO细胞，在其培养上清检测到BTLA胞外段（sBTLA）的表达。DCs经抗原肽刺激后BTLA、HVEM表达均上调，加入含sBTLA的上清处理后上调B7—1，上清中分泌的IL-12增加，与脾细胞共培养时促进细胞增殖和IL-2、IFN-γ的分泌；体内基因转染psBTLA促进DCs表达B7-1以及抑制肿瘤生长。结论通过sBTLA阻断BTLA—HVEM共抑制通路，可以进一步促进DCs的功能，更好地激活淋巴细胞，促进抗肿瘤免疫应答。

英文摘要：

Objective To explore the effect of blocking BTLA-HVEM （herpesvirus entry mediator-B and T lymphocyte attenuator） pathway on dendritic cell function and the related immunological mechanisms. Methods Murine BTLA extracellular domain eukaryotic expression vector psBTLA was constructed by gene recombination and transfected CHO by Lipofection method. Mouse bone marrow cells were induced to differentiate into DCs by GM-CSF plus IL-4. Expression of BTLA and HVEM on DCs was detected after HSPT0-TC-1 peptide complex stimulation by FACS. Expression of B7-1 and secretion of IL-12 were detected after HSP70-TC-1 peptide complex plus psBTLA transfected CHO culture supernatant stimulation on DCs. Pretreated DCs co-cultured with the same genetic background mouse splenocytes and lymphocytes proliferation and cytokine secretion were detected. Effect of psBTLA gene transfer in vivo on B7-1 expression of DCs and tumor growth on tumor-bearing mice was detected. Results Extracellular domain of murine BTLA was successfully constructed, psBTLA stable transfection CHO cells were obtained and expression of BTLA extracellular domain（sBTLA） was detected the in its culture supernatant. BTLA and HVEM expression of DCs were increased after stimulation by the antigen pep- tide complex. When DCs were treated with antigen peptide complex plus culture supernatant containing sBTLA, B7-1 expression and IL-12 secretion were increased. Co-cultured with splenocytes, lymphocytes proliferation and cytokine secretion, such as IL-2 and IFN-γ were also increased. Gene transfection with psBTLA in vivo promoted B7-1 expression on DCs and inhibited cervical cancer cells growth. Conclusion Blockade of BTLA-HVEM inhibitory pathway with sBTLA can further improve DCs function, activation of lymphocytes and promote antitumor immune response.