Analysis of CXCR4 expression in UT-7 and UT-7/fus cells. Northern blot (A and B) and RT-PCR (C and D) were performed on total RNA obtained from human peripheral blood lymphocytes and parental UT-7 and UT-7/fus cells. Northern blot was hybridized with CXCR4 c-DNA (A) or GAPDH (B) probes. RT-PCR products were hybridized with an end-labeled oligoprimer internal to CXCR4 c-DNA (C). As control, RT-PCR for β2-microglobulin19 was performed (D).