HLA class I expression in medulloblastoma cell lines. a Flow cytometry analysis of three medulloblastoma cell lines stained with W6/32 monoclonal antibody followed by FITC conjugated anti-mouse Ig (bold lines) or control samples with primary antibody omitted (plain lines). b RT-PCR analysis using TAP1, TAP2, β2m, HLA-A, HLA-B, and CD45 specific primers. cDNAs obtained from the DAOY, D283 medulloblastoma and U937 leukemia (positive control) cell lines were used as templates. Negative control consisted of samples with no cDNA (H2O)