Understanding the regulation of immune responses is central for control of autoimmune and infectious disease. In murine models of autoimmunity and chronic inflammatory disease, potent regulatory T lymphocytes have recently been characterized. Despite an explosion of interest in these cells, their relevance to human disease has been uncertain. In a longitudinal study of malaria sporozoite infection via the natural route, we provide evidence that regulatory T cells have modifying effects on blood-stage infection in vivo in humans. Cells with the characteristics of regulatory T cells are rapidly induced following blood-stage infection and are associated with a burst of TGF-β production, decreased proinflammatory cytokine production, and decreased antigen-specific immune responses. Both the production of TGF-β and the presence of CD4 +CD25+FOXP3+ regulatory T cells are associated with higher rates of parasite growth in vivo. P. falciparum-mediated induction of regulatory T cells may represent a parasite-specific virulence factor. Copyright © 2005 Elsevier Inc.
Walther, M., Tongren, J. E., Andrews, L., Korbel, D., King, E., Fletcher, H., … Hill, A. V. S. (2005). Upregulation of TGF-β, FOXP3, and CD4+CD25+ regulatory T cells correlates with more rapid parasite growth in human malaria infection. Immunity, 23(3), 287–296. https://doi.org/10.1016/j.immuni.2005.08.006