IκBα突变体基因修饰树突状细胞降低同种T细胞的反应性

Immune tolerance of allogeneic T cells induced by dendritic cells genetically en gineered to express IκBα mutant

目的观察IκBα突变体基因修饰的树突状细胞(IκBαM-DC)对同种T细胞的反应性。方法利用腺病毒载体将IκBαM基因转染WF大鼠骨髓树突状细胞(DC),Western-blot法检测DC中IκBα、IκBαM基因的表达;用流式细胞仪检测DC中共刺激分子MHCⅡ、CD80、CD86、CD40的表达;酶联免疫法(ELISA)分析DC分泌IL-12的含量。通过混合淋巴细胞反应(MLR)分析Lewis大鼠T细胞对IκBαM-DC刺激的增殖能力,二次MLR检测IκBαM-DC诱导的T细胞抗原特异性的低反应性。结果IκBαM抑制DC共刺激分子MHCⅡ、CD80、CD86、CD40的表达及IL-12分泌。同种T细胞对IκBαM-DC刺激的增殖能力较未转染的DC反应明显降低;T细胞低反应具有抗原特异性。结论表达IκBα突变体基因的DC能降低同种T细胞的反应性。

Objective To assess the immune tolerance of allogeneic T cells induced by dendritic cells genetically engineered to express IκBα mutant. Methods DCs were prepared from WF rat bone marrow cells and modified by IκBαM gene with adenovirus vector, and then the expression of IκBα and IκBαM was detected by Western-blot. The cell-surface expression of costimulatory molecules （CD80, CD86 and CD40） was detected by flow cytometry, and the production of IL-12 in DCs culture supermatant was determined by ELISA. The ability to stimulate the proliferation of Lewis rat T cells was analyzed by mixed leukocyte reactions （MLR）. The antigen-specific T cell hyporesponsiveness was tested by secondary MLR. Results IκBαM suppressed the cell-surface expression of costimulatory molecules and inhibited the production of IL 12. IκBαM-DC showed reduced ability to stimulate T cell sproliferation, and potential to induce antigen-specific T cell hyporesponsiveness. Conclusion Immune tolerance of T cells can be induced by dendritic cells genetically engineered to express IκBα mutant.