Supplementary MaterialsSupplementary Information 41467_2017_1728_MOESM1_ESM. heterogeneity of Compact disc4 TEMRA cells and provides insights into T-cell responses against DENV and other viral pathogens. Introduction ABT-492 (Delafloxacin) ABT-492 (Delafloxacin) T cells have important functions in conferring immunological protection against infectious pathogens by generating effector cells that mediate antigen control and by forming memory cells that provide long-term protective immunity against recurring infections. Effector and memory T cells are diversified into distinct subsets with specialized functions, and numerous molecules have been used to help identify those subsets and characterize the heterogeneity of both CD4 and CD8 T cells1. On the basis of the expression of two surface molecules, CD45RA and CCR7, human T cells can be divided into four subsets, including CD45RA+CCR7+ naive (TN), CD45RA?CCR7+ central memory (TCM), CD45RA?CCR7? ABT-492 (Delafloxacin) effector memory (TEM), and CD45RA+CCR7? effector memory re-expressing CD45RA (TEMRA) T cells1,2. TEMRA cells have been studied in the CD8 T-cell area mainly, where they are located at appreciable frequencies generally in most people2C5. In comparison, the frequency of CD4 TEMRA cells varies between individuals which range from 0 drastically.3% to nearly ABT-492 (Delafloxacin) 18% of total CD4 T cells within an apparently healthy human population6, and their functional part is much less clear. Accumulating research possess indicated that attacks with pathogens such as for example human being cytomegalovirus (CMV) and dengue disease (DENV) are connected with an development of Compact disc4 TEMRA cells7C9. Furthermore to exhibiting a Compact disc45RA+CCR7? phenotype, Compact disc4 TEMRA cells have already been seen as a reduced manifestation of Compact disc27 and Compact disc28 also, aswell as improved expressions of Compact disc57 and effector substances such as for example perforin and granzyme B that resemble even more terminally differentiated condition5,9,10. Research of DENV-infected people suggested an operating significance of Compact disc4 TEMRA cells9. It had been shown how the rate of recurrence of Compact disc4 TEMRA cells expands like a function of DENV disease history9 progressively. Compact disc4 TEMRA cells connected with this development possess a cytotoxic phenotype and show increased expression from the chemokine receptor CX3CR1, which can be connected with both Compact disc4 and Compact disc8 T cells that have cytotoxic potentials9,11C13. Furthermore, improved magnitude and features of Compact disc4 TEMRA cells correlate with HLA allelic variations that are ABT-492 (Delafloxacin) connected with comparative resistance to severe DENV diseases, suggesting that CD4 TEMRA cells may have a Itgax protective function in this setting9,14. Nevertheless, how CD4 TEMRA cells differ from other memory-phenotype CD4 T cells such as TCM and TEM cells at the global level is less well defined. Lastly, it remains to be addressed whether CD4 TEMRA cells represent a homogenous population, or heterogeneity exists within this subset. In this study, we set out to comprehensively define the immune signatures of CD4 TEMRA cells. We find that CD4 TEMRA cells have highly diverse gene expression profiles in different donors. In some donors, TEMRA cells are similar to conventional TEM cells. However, in other donors, by comparison with their TCM and TEM counterparts, TEMRA cells display a unique gene expression profile, which is characterized by the upregulation of cytotoxic molecules such as GPR56, CD244, perforin and granzyme B, as well as transcription factors such as Runx3, T-bet and Hobit. We show that this variability between donors is due to the presence of two primary sub-populations of TEMRA cells, with the TEM-like GPR56? TEMRA subpopulation being present in all donors with similar frequency, while the cytotoxic GPR56+ TEMRA subpopulation have high variability from donor to donor with evidence for clonal expansion. Furthermore, the majority of DENV-specific, as well as CMV- and EpsteinCBarr virus (EBV)-specific CD4 TEMRA cells are found in the GPR56+ TEMRA subset. Thus, GPR56+ TEMRA.