Figure 1From: Phorbol esters and CAMP differentially regulate the expression of CD4 and CD8 in human thymocytesNorthern blot analysis of the effect of PMA and cAMP on CD4 and CD8 mRNA levels in human thymocytes. Cells were incubated for 4 h at 37°C in culture media as described in the methods, in the absence (lane 1) or in the presence of 10 nM PMA (lane 2) or 1 mM dibutyryl cAMP plus 1 mM IBMX (lane 3), and the combination of both (lane 4). RNA was subsequently extracted and analyzed. The expression of the proto-oncogene c-Ha-ras served as an internal control.Back to article page