Fig 1: Phenotypic and clonal diversity of decidual T cells at term(A) Frequencies of naive and memory CD4 and CD8 T cell subsets in blood (n = 55) and decidua (n = 6) at T3 using flow cytometry. Error bars represent the mean and standard error of the mean (SEM).(B) UMAP of matched decidual and blood memory T cells at term (n = 4), annotated by surface- and gene expression markers.(C) Stacked violin plots of key gene markers of memory T cell subsets within clusters using normalized transcript counts. Red font indicates clusters shared between blood and decidual leukocytes.(D) Frequencies of CD4 (top) and CD8 T cells (bottom) in blood (n = 3) and decidua (n = 9) expressing CD69 and CD103. Error bars represent the mean and standard error of the mean (SEM).(E and F) Frequencies of (E) PD-1+ CD4 and CD8 T cells (n = 3/group) and (F) Tregs within CD4 (n = 3 for blood and n = 9 for decidua). Error bars represent the mean and standard error of the mean (SEM).(G) Th1 cytokine responses of blood (n = 3) vs. decidual (n = 9) CD4 (left) and CD8 (right) T cells in response to 4 h PMA/ionomycin stimulation.(H) Treg and Th17 cytokine responses of blood (n = 3) vs. decidual (n = 3) CD4 T cells following 4 h PMA/ionomycin stimulation.(I) T cell clone sizes in blood and decidua at term.(J) Chao diversity of T cell clones from blood and decidua within each donor.(K) Clonal tracking of the 10 most abundant blood T cell clones in the decidua (top panel) and blood (bottom panel) in each donor. ****p < 0.0001, ***p < 0.001, **p < 0.01, and *p < 0.05.