【摘要】 为探讨两个口腔鳞癌细胞系 (KB和Tca81 1 3)中HLAI类抗原的表达水平及其异常的分子机制。利用流式细胞术、Westernblot检测细胞系中HLAI类抗原在蛋白水平的表达 ;RT PCR检测细胞系在转录水平的表达。结果两个口腔鳞癌细胞系中HLAI类抗原蛋白水平的表达下调 ;RT PCR结果显示Tca81 1 3细胞系中A、B、C、LMP2、LMP7、LMP1 0基因的mRNA表达下调 ;在KB细胞系中除了A、B、C、LMP7、LMP1 0基因的mRNA表达下调 ,LMP2、PA2 8α基因的mRNA表达显著减少或缺失 ;而TAP1、TAP2、Tapasin基因在mRNA水平的表达无改变。IFN γ诱导后纠正了多个基因在mRNA水平的异常表达。两个口腔鳞癌细胞系中HLAI类抗原表达下调 ,且多基因在转录水平的异常也即转录效率的低下很可能是该下调的重要原因更多还原

【Abstract】 To investigate the mechanism of down regulation of HLA class I molecules on two cell lines of oral squamous cell carcinoma,the expressions of HLA class I molecules were determined by flow cytometry and Western blotting assay using a panel of antibodies To characterize the down regulation of HLA molecule,the analysis was extended to RNA level by RT PCR by using the specific primers It was found that the expression of HLA class I molecules of these two tumor cell lines was reduced in comparison with those of the normal epithelial cell line (Hacat) as determined with flow cytometry and Western blotting The results by using RT PCR showed that the expressions of HLA A,B,C,LMP2,LMP7 and LMP10 gene mRNA were down regulated in case of the Tca8113 cell line,but in case of KB cell line,the expressions of HLA A,B,C,LMP7,LMP10 gene mRNA were down regulated with marked reduction or deletion of the LMP2 and PA28α gene mRNA,yet,those of the TAP1,TAP2,Tapasin gene mRNA showed no any changes Treatment with IFN γ could enhance the expressions of HLA A,B,C,LMP7,LMP10 transcripts and restore those of LMP2 and PA28 transcripts It concludes that the abnormal expressions of HLA class I molecules in oral squamaous cell carcinoma cell lines may be presumably due to the low efficiency of HLA gene transcription更多还原