TH1 AND TH2 CYTOKINE RESPONSES AFTER MEASLES ANTIGEN STIMULATION IN-VITRO IN BONE-MARROW TRANSPLANT PATIENTS - RESPONSE TO MEASLES VACCINATION

In seronegative autologous bone marrow transplanted (ABMT) patients, a sustained cell-mediated immunity (CMI) has been shown to impair the a ntibody response after measles vaccination, To investigate if this mig ht be caused by a preferential Th1 cytokine response, interferon (IFN) -gamma and interleukin (IL)-10 production of peripheral blood mononucl ear cells (PBMC) was analyzed after measles antigen (M-ag) stimulation in vitro. The non-specific immune response was measured by IFN-alpha, and IL-12 analyses, Fifty non-vaccinated patients following ABMT or a llogeneic bone marrow transplantation (BMT) were included, IFN-gamma p roduction was significantly higher in patients with a retained CMI to measles than in patients without (2.3 vs 0.8 IU/ml; P = 0.01), Only a non-significant tendency was seen in IL-10 production (48.6 vs 26.7 pg /ml; NS), whereas no difference was found in IFN-alpha or IL-12 produc tion, A positive correlation between IFN-gamma and IL-10 production wa s found (r(s) = 0.49; P < 0.001), After vaccination of 14 ABMT childre n, there was an increase in PBMC IFN-gamma production in vitro (2.5 vs <0.1 IU/ml; P < 0.05), whereas no changes were seen in the IL-10, IFN -alpha, or antibody levels, These results suggest that bath Th1 and Th 2 cytokine production are increased by hl-ag stimulation in patients w ith a retained CMI to measles, but the Th1 response seems to be strong er, The preferential Th1 stimulation and increase in IFN-gamma product ion after vaccination may lead to a reduction in the humoral immune re sponse which may explain the negative correlation between antibody pro duction and T cell reactivity prior to vaccination.