Characterization of a new subset of CD8+HLA-DR+ T cells in human decidua

ARIEL PODHORZER; MARIA E SOLANO; ANDRES P MACHICOTE; PETRA C ARCK; EVA TOLOSA; LEONARDO FAINBOIM

Congreso; 13th Congress of the International Society for Immunology of Reproduction; 2016

We previously showed that human peripheral blood CD8+HLA-DR+ T cells represent a natural regulatory T cell subset, which acts through cell contact involving CTLA-4. Hereby, our aim was to characterize this T cell subset in first trimester human decidua.CD45+ cells were sorted from elective pregnancy termination tissues (n=8) and stained for surface and intracellular markers. Intracellular staining was performed after PMA stimulation using fixed and permeabilized cells. Flow cytometry analysis revealed that 23±15% of gated lymphocytes were CD3+ cells, among which CD8+ and CD4+ T cell frequencies were 43±13% and 47±16% respectively. Whilst HLA-DR+ cells constituted 42±7% of CD8+ T cells, CD4+Foxp3+ Tregs represented 12.4±6.7% of CD4+ cells. CD8+HLA-DR- cells exhibited a more differentiated CD45RO+CD27-CD28- phenotype (p