RFX and CIITA expression profiles in malignant T cells. (A) The presence of RFX5, RFXAP, RFXB, and CIITA mRNA was detected using RT-PCR analysis on cDNA from several T-ALL cell lines and the T-cell lymphoma HUT78. (B) The usage of CIITA promoters PI, PIII, and PIV was investigated on HLA-DR–negative and HLA-DR–positive malignant T cells using RT-PCR analysis. GAPDH was used as control for equal cDNA loading. DC indicates dendritic cells.