Fig. 6.

Quantitative analysis of the expression of MHCII molecules after siRNA-mediated specific knockdown of the CIITA-PIV isoform. Cytofluorometric analysis of Me10538, M14 and U87 cells transiently transfected with siRNAs specific for HLA-DRA, CIITA, CIITA-PIV, and a negative control siRNA. The density of HLA-DR and HLA-DQ molecules on the cell surface was measured as fluorescence from cells stained with specific antibodies and was expressed as MFI. The results are plotted as the mean ± SEM of fold change of MFI value relative to sham-transfected cells as a control in three independent experiments. The method of Student was used to evaluate the statistical significance of the differences between mean fold change of the MFI values. The asterisks (*) indicate a p-value less than 0.05 using a two-tailed t test.