SPECIFIC INTERFERON-GAMMA PRODUCING CD4(-CELLS AFTER AUTOLOGOUS EBV-BSTIMULATION - THE NECESSITY OF RESTIMULATION() AND CD8(+) T)

The response of T cells to produce interferon-gamma, to proliferate an d to become cytotoxic after specific stimulation with low dose (2%) au tologous EBV-B cells was investigated in 15 EBV seropositive and five seronegative patients. A significantly higher number of interferon-gam ma producing cells (56 +/- 24 per 10(5) T cells) were found in a spot ELISA in EBV positive than in EBV negative patients (7 +/- 2 spots, P< 0.01) and it was only found with restimulation after 5-12 days of prim ary culture. No correlation was found between the extent of interferon -gamma production, cytotoxicity or profileration. Specificity of EBV-i nduced interferon-gamma production was demonstrated by comparison of t he response to allogeneic EBV-B cells or IL-2 in the restimulation pha se. The response was stronger in CD8(+) T cells than in CD4(+) T cells and could be blocked in the restimulation phase with HLA class I and class II antiserum, respectively.