Effects of SV40 infection on expression of surface markers on human B cells.

<p>Surface expression levels of lymphocyte activation markers (A) CD69 and (D) CD25, and of costimulation molecules (B) CD80 and (C) CD86, were examined by flow cytometry. BJAB, DG75, and CEM cells were either mock-infected or infected with SV40 strains 776-1E, 776-2E, or 776-2E-SM1 and were harvested and analyzed at various d.p.i. Harvest times shown are indicated by the number on each histogram. The cells were stained with anti-CD69-PE, anti-CD80, anti-CD86, or anti-CD25-PE antibodies (BD Pharmingen) and were analyzed by flow cytometry. These results show that SV40 infection affects the expression of lymphocyte surface markers on human B cells by up-regulating CD69 and CD25 and by down-regulating CD80 and CD86. These effects were most pronounced following infections by the miRNA mutant 776-2E-SM1. CEM T cells showed no change in surface expression of CD69, CD80, or CD86 at any day after SV40 infection.