Effect of blood type on anti-α-Gal immunity and the incidence of infectious diseases

The identification of factors affecting the susceptibility to infectious diseases is essential toward reducing their burden on the human population. The ABO blood type correlates with susceptibility to malaria and other infectious diseases. Due to the structural similarity between blood antigen B and Gal alpha 1-3Gal beta 1-(3)4GlcNAc-R (alpha-Gal), we hypothesized that self-tolerance to antigen B affects the immune response to alpha-Gal, which in turn affects the susceptibility to infectious diseases caused by pathogens carrying alpha-Gal on their surface. Here we found that the incidence of malaria and tuberculosis, caused by pathogens with alpha-Gal on their surface, positively correlates with the frequency of blood type B in endemic regions. However, the incidence of dengue fever, caused by a pathogen without alpha-Gal, was not related to the frequency of blood type B in these populations. Furthermore, the incidence of malaria and tuberculosis was negatively correlated with the anti-alpha-Gal antibody protective response. These results have implications for disease control and prevention.