Transcriptional memory-like imprints and enhanced functional activity in γδ T cells following resolution of malaria infection

Abstract

{gamma}{delta} T cells play an essential role in the immune response to malaria infection. However, long-lasting effects of malaria infection on the {gamma}{delta} T cell population still remain inadequately understood. This study investigated transcriptional changes and memory-like functional capacity of malaria pre-exposed {gamma}{delta} T cells using a Plasmodium chabaudi infection model. We show that multiple genes associated with effector function (chemokines, cytokines and cytotoxicity) and antigen-presentation were upregulated in P. chabaudi-exposed {gamma}{delta} T cells compared to {gamma}{delta} T cells from naive mice. This transcriptional profile was positively correlated with profiles observed in conventional memory CD8+ T cells and was accompanied by enhanced reactivation upon secondary encounter with Plasmodium-infected red blood cells in vitro. Collectively our data demonstrate that Plasmodium exposure result in "memory-like imprints" in the {gamma}{delta} T cell population and also promotes {gamma}{delta} T cells that can support antigen-presentation during subsequent infections.