Associations between race, sex and immune response variations to rubella vaccination in two independent cohorts

Introduction: Immune response variations after vaccination are influenced by host genetic factors and demographic variables, such as race, ethnicity and sex. The latter have not been systematically studied in regard to live rubella vaccine, but are of interest for developing next generation vaccines for diverse populations, for predicting immune responses after vaccination, and for better understanding the variables that impact immune response. Methods: We assessed associations between demographic variables, including race, ethnicity and sex, and rubella-specific neutralizing antibody levels and secreted cytokines (IFN-gamma, IL-6) in two independent cohorts (1994 subjects), using linear and linear mixed models approaches, and genetically defined racial and ethnic categorizations. Results: Our replicated findings in two independent, large, racially diverse cohorts indicate that individuals of African descent have significantly higher rubella-specific neutralizing antibody levels compared to individuals of European descent and/or Hispanic ethnicity (p<0.001). Conclusion: Our study provides consistent evidence for racial/ethnic differences in humoral immune response following rubella vaccination. (C) 2014 Elsevier Ltd. All rights reserved.