Transcriptional signature of CD4hiCD38hi T cells from patients with Plasmodium falciparum or Plasmodium knowlesi malaria

We observed by flow cytometry a population of CD4 T cells expressing very high levels of the coreceptor CD4 and the ectoenzyme CD38 (termed CD4hiCD38hi) in the peripheral blood of patients from Sabah and Papua with Plasmodium falciparum or Plasmodium knowlesi malaria. CD4hiCD38 T cells express genes associated with type 1 regulatory T cells. PBMCs isolated from adult patients with P. falciparum or P. knowlesi malaria in Papua or Sabah were sorted by flow cytometry into populations of CD4hiCD38hi T cells or CD4norm T cell populations. Immediately following the sort, the cells were stimulated with PMA and Ionomycin for 3 hours and then lysed and gene expression was analysed using the nCounter Custom Codeset Watkins_1_c3950. CD4hiCD38hi T cells and CD4norm T cells were sorted from 6 patients with P. falciparum from Sabah and 6 from Papua, and also from 6 patients with P. knowlesi from Sabah.