Plasmodium vivax infection induces expansion of activated naïve/memory T cells and differentiation into a central memory profile

Abstract Immunity to malaria is widely believed to wane in the absence of reinfection, but direct evidence for the presence or absence of durable immunological memory to malaria is limited. Here, we characterized the profile of circulating naive and memory (including central and effector) CD4 + T cells responses of individuals naturally infected by Plasmodium vivax . In the current study, we demonstrated that acute P. vivax infection induces a significant increase in the absolute number of both naive and memory cells, which were responsible for the production of anti-inflammatory (IL-10) and pro-inflammatory (IFN-γ) cytokines. Finally, we described the profile of memory cell subtypes (T CM -CD45RO high CCR7 + and T EM -CD45RO high CCR7 − ), as well as the pattern of cell migration based on CD62L selectin expression, demonstrating that P. vivax -infected donors presented with a predominantly central memory cell profile. Our results indicate that the expansion of both naive and memory T cells, responsible for the production of both pro-inflammatory and regulatory cytokines, which might also contribute to the modulation of immune responses during P. vivax infection.