HIV remains a significant cause of morbidity and mortality around the world. The human body produces more IgA than any other immunoglobulin, especially in mucosal secretions. However, the importance of IgA in both protection from HIV-1 and control of HIV-1 disease progression is highly controversial. Results from the only protective human HIV vaccine trial associated plasma IgA with reducedvaccine efficacy. In contrast, recent studies suggest that mucosal HIV-specific IgA may be protective. We are exploring the mechanisms behind both the protective and immunomodulatory role of IgA in the control of HIV-1 and other infectious diseases.
Schematic diagram of immunoglobulin A (IgA) subclasses IgA1 and IgA2, glycosylation patterns and their respective heterogenous molecular forms. In blood and tissue compartments (a) monomeric IgA (mIgA) and to a lesser extent (b) dimeric IgA (dIgA) [two IgA monomer Fc portions connected via a joining (J) chain] are present. dIgA is secreted through epithelial cells via the polymeric immunoglobulin receptor (pIgR) into the mucosal lumen with secretory component (SC) to form (c) secretory IgA (sIgA).
Davis, S. K., et al. (2019). "Serum IgA Fc effector functions in infectious disease and cancer." Immunology and cell biology.