Greater ethnic diversity correlates with lower HIV prevalence in Africa: justification for an alloimmunity vaccine

Abstract

Christopher Zamani, Jared D Elzey, James EK Hildreth Center for AIDS Health Disparities Research at Meharry Medical College, Nashville, Tennessee, USA Purpose: After decades of research, AIDS continues to be a major pandemic and to date, adaptive immunity vaccine designs have had little to no success. Data indicate the alloimmune response is a potent mitigator of human immunodeficiency virus (HIV) infection, for which experiments of nature should be demonstrable to justify pursuit of an alloimmune vaccine strategy. We sought to determine if large-scale alloimmune diversity correlates with lower HIV infection rates. Methods: Using published data of African linguistic groups to determine sub-Saharan country ethnicity profiles as a proxy for human leukocyte antigen (HLA) diversity, a correlation analysis was performed against respective sub-Saharan country HIV infection rates. Ethnicity data from 37 sub-Saharan nations in 2003 and from 38 nations in 2005 were used to calculate the Meyers-Macintosh ethnic diversity score for each nation as the independent variable. World Health Organization data on HIV infection rates for the same countries were used as the dependent variable. The main outcome measure was the correlation coefficient of ethnic diversity versus HIV infection rate. Results: A significant negative correlation was shown between ethnic diversity and HIV infection: for 2003 data, -0.4586 (two-tailed P-value of 0.0043); and, for 2005 data, -0.3866 (two-tailed P-value of 0.0165). Conclusion: In conjunction with substantial evidence that alloimmunity confers protection against HIV transmission and recent work identifying specific anti-HIV mechanisms, this analysis strongly justifies an HLA-based alloimmune vaccine strategy against HIV. Keywords: AIDS, adaptive immunity, human leukocyte antigen (HLA)