FIGURE 4.

IFN-γ can reduce EBV-induced enrichment of IgD⁻CD27⁺ B cells. PBMC from 2-y-old CMV⁻ children (n = 3) were subjected to in vitro EBV infection and cultured for 14 d. Recombinant human IFN-γ was added either once at 10,000 pg/ml after 24 h, or at 1,000 or 500 pg/ml after 24 h and subsequently every 72 h. (A) One representative example of CD19⁺ B cell subset frequencies in control and EBV-infected PBMC cultures after addition of rIFN-γ. (B) Combined data from all three independent experiments shown as percentage IFN-γ–mediated restriction (EBV only cultures represent 0% restriction) on frequencies of CD19⁺IgD⁻CD27⁺ cells in EBV-infected cultures.