from these results it may be concluded that ( a ) lfa-1 expression can vary considerably according to the culture conditions , ( b ) the expression of this antigen on the surface of non-expressing variants can be induced by phorbol ester , and ( c ) in both cases , the change in expression can be reversed completely by replacing the culture medium or by removing phorbol myristate acetate from it .
C0031586
phorbol
C0039654
phorbol myristate