CEA-rV对小鼠巨噬细胞抗原呈递功能的影响

The effect of CEA-rV on antigen-presenting ability of mouse macrophages

目的 探讨癌胚抗原重组痘苗病毒 (CEA rV)对巨噬细胞 (MΦ)抗原呈递功能的影响。方法 采用混合淋巴细胞反应 (MLR) ,检测接种CEA rV小鼠MΦ的抗原呈递功能。采用流式细胞术 (FCM )检测MΦMHC Ⅰ (H 2Kb)、MHC Ⅱ (I Ab)及B7(B7 2 )分子的表达。采用荧光抗体直接染色法 ,检测CEA+肿瘤细胞H 2Kb和I Ab分子的表达。结果 腹腔接种CEA rV小鼠MΦ组 (CEA rVMΦ组 )T细胞分泌IL 2的水平较接种W VV株及NS组显著增强(P <0 .0 1)。小鼠腹腔MΦ上I Ab和B7 2分子的固有表达较低 (分别为 41.7%和 13.7% )。接种W VV株后 ,I Ab 及B7 2分子的表达改变不明显 (分别为 44 .3%和 15 .1% ) ;而接种CEA rV后 ,I Ab及B7 2分子的表达明显增强 (分别为87.2 %和 39.5 % )。各组CEA+肿瘤细胞MHC Ⅰ分子呈强表达 ,但却无MHC Ⅱ分子。结论 腹腔接种CEA rV小鼠的MΦ ,可使MΦ其抗原呈递功能显著增强。MΦ的MHC Ⅱ与B7 2分子表达的增强 ,可能是其抗原呈递功能增强的主要原因 ,提示MHC Ⅱ与B7 2分子可能与CEA

Aim To explore the effect of recombinant vaccinia virus containing CEA(CEA-rV) on antigen-presenting ability of MΦs. Methods The antigen-presenting ability of CEA-rV inoculated mouse MΦs was detected by MLR. Expression of MHC-Ⅰ, Ⅱand B7 molecules on murine MΦs were detected using FCM. Expression of H-2K band I-A bon CEA-positive tumor cells were tested by direct fluorescence staining. Results IL-2 level secreted by T cells in CEA-rV inoculated group was significantly higher than those in W-VV-inoculated and NS-inoculated groups (P<0.01). Constitutive expressions of I-A band B7-2 molecules on murine peritoneal MΦs were lower, being 41.7% and 13.7%, respectively. After inoculation of W-VV, the changes of expressions of I-A b and B7-2 molecules on MΦs were unremarkable (44.3% and 15.1%, respectively), but after inoculation of CEA-rV, expressions of I-A b and B7-2 molecules on MΦs were markedly enhanced (87.2% and 39.5 %, respectively). Ⅰ molecule was strongly expressed on CEA-positive tumor cells in 3 groups, but MHC Ⅱ molecule was not expressed. Conclusion CEA-rV may enhance antigen-presenting ability of CEA-rV inoculated mouse MΦs. The upregulaion of I-A band B7-2 expressions on CEA-rV inoculated mouse MΦs may be the main reason for enhancement of antigen-presenting ability induced by CEA-rV, suggesting that I-A band B7-2 molecules may play an important role in antitumor immune response of CEA-rV.