Influence of host genetic variation on rubella-specific T cell cytokine responses following rubella vaccination

The variability of immune response modulated by immune response gene polymorphisms is a significant factor in the protective effect of vaccines. We studied the association between cellular (cytokine) immunity and HLA genes among 738 schoolchildren (396 males and 342 females) between the ages of 11 and 19 years, who received two doses of rubella vaccine (Merck). Cytokine secretion levels in response to rubella virus stimulation were determined in PBMC cultures by ELISA. Cell supernatants were assayed for Th1 (IFN-gamma, IL-2, and IL-12p40), Th2 (IL-4, IL-5, and IL-10), and innate/proinflammatory (TNF-alpha, GM-CSF, and IL-6) cytokines. We found a strong association between multiple alleles of the HLA-DQA1 (global p-value 0.022) and HLA-DQB1 (global p-value 0.007) loci and variations in rubella-specific IL-2 cytokine secretion. Additionally, the relationships between alleles of the HLA-A (global p-value 0.058), HLA-B (global p-value 0.035), and HLA-C (global p-value 0.023) loci and TNF-alpha secretion suggest the importance of HLA class I molecules in innate/inflammatory immune response. Better characterization of these genetic profiles could help to predict immune responses at the individual and population level, provide data on mechanisms of immune response development, and further inform vaccine development and vaccination policies.