Study on the expression of B7 molecule on DC inhibited by special siRNA

Objective To investigate the expression of CD80 and CD86 costimulatory molecule on dendritic Cells(DC) inhibited by small interfering RNA(siRNA).Methods Three different siRNA(siRNA1-targeted against CD80,siRNA2-targeted against CD86 and siRNAc) were designed and synthesized and transfected into DC with liposome.At 24,48 and 72h after transfection,the expression of CD80 and CD86 gene were detected by semi-quantitative RT-PCR,and the protein of CD80 and CD86 were assayed by Western blot.Results The results of semi-quantitative RT-PCR showed the mRNA of CD80 and CD86 were inhibited.The rate of suppression of CD80 were(50.0±3.63)%,(66.8±4.12)% and(76.6±4.87)% by siRNA1 at 24,48 and 72h after transfection,respectively.The rate of suppression of CD86 were(53.0±3.70)%,(60.5±3.92)% and(73.4±4.46)% by siRNA2 at the same time.At 48 and 72h after transfection,the degrees of reduction with siRNA1 and siRNA2 were(67.3±4.80)%,(80.9±5.23)%,(60.7±4.15)% and(74.7±4.63)%,respectively.Conclusion The siRNA could reduce the expression of B7 protein and B7 mRNA level.The silencing effect on B7 mRNA by siRNA may contribute to costimulatory blockade.