Functional and transcriptional heterogeneity within the massively expanding HLADRCD38 CD8 T cell population in acute febrile dengue patients.

CD8 T cells play a crucial role in protecting against intracellular pathogens such as viruses by eliminating infected cells and releasing anti-viral cytokines such as interferon gamma (IFNγ). Consequently, there is significant interest in comprehensively characterizing CD8 T cell responses in acute dengue febrile patients. Previous studies, including our own, have demonstrated that a discrete population of CD8 T cells with HLADR CD38 phenotype undergoes massive expansion during the acute febrile phase of natural dengue virus infection. Although about a third of these massively expanding HLADR CD38 CD8 T cells were also CD69 when examined , only a small fraction of them produced IFNγ upon peptide stimulation. Therefore, to better understand such functional diversity of CD8 T cells responding to dengue virus infection, it is important to know the cytokines/chemokines expressed by these peptide-stimulated HLADRCD38 CD8 T cells and the transcriptional profiles that distinguish the CD69IFNγ, CD69IFNγ, and CD69IFNγ subsets.