Vaccine
http://www.sciencedirect.com/science/journal/0264410X/32/17
Volume 32, Issue 17, Pages 1897-2016 (7 April 2014)

Associations between race, sex and immune response variations to rubella vaccination in two independent cohorts
Original Research Article
Pages 1946-1953
Iana H. Haralambieva, Hannah M. Salk, Nathaniel D. Lambert, Inna G. Ovsyannikova, Richard B. Kennedy, Nathaniel D. Warner, V.Shane Pankratz, Gregory A. Poland

Abstract
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 (IFNγ, 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.