GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE304nnn/GSE304421/primaryOK200OtherMus musculus Expression profiling by high throughput sequencingOtherhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE304421GEOGSEfalseSingle-cell multiomics reveals a CD4+ TH1 driven response to Pneumocystis in immunocompetent hostsUnderstanding immune mechanisms by which Pneumocystis is cleared in immunocompetent hosts can inform strategies for preventing and treating Pneumocystis pneumonia. We used a co-housing exposure model of mouse Pneumocystis (P. murina) infection to characterize the roles of pulmonary immune cell populations in immunocompetent (C57BL/6) mice at single-cell level. CD4+ TH1 cells showed the greatest increase and clonal expansion following P. murina infection, with less pronounced increases in TH17 and TfH cells. We also observed reduced TCR diversity post-P. murina infection, and identified expanded clonotypes with limited overlap between animals, suggesting antigenic variation. Infected mice showed differential expression of pro-inflammatory cytokines IL-21, Cxcl9, Ly6a, co-stimulatory molecule Ox-40 (CD134), and regulatory genes Lag3 and Ctla4, indicating a regulated immune response. Pathway analyses predicted IFN‐γ centered cytokine interactions which presumably enhance killing of P. murina organisms by macrophages. Thus, we demonstrate a predominant CD4+ TH1 cell response in immunocompetent hosts, and delineate expanded TCR clonotypes in Pneumocystis infected mice, providing insights for development of immunomodulatory therapies.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 musculus