Functional and transcriptional heterogeneity within the massively expanding HLADR + CD38 + CD8 T cell population in acute febrile dengue patients.

Importance: 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 ^high when examined ex vivo , only a small fraction of them produced IFNγ upon in vitro 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 HLADR ⁺ CD38 ⁺ CD8 T cells and the transcriptional profiles that distinguish the CD69 ⁺ IFNγ ⁺ , CD69 ⁺ IFNγ ^- , and CD69 ^- IFNγ ^- subsets.
Competing Interests: The authors declare no conflict of interest.