Decidual and peripheral CD4⁺T cells show different surface phenotypes and function. Flow cytometry was used to investigate the surface phenotype and cytokine production of the decidual and peripheral CD4⁺ T cells (A-D). The decidual CD4⁺ T cells constitute 77.57% ± 11.92% of CD45RO⁺ memory T cells, 3.64% ± 0.62% of CD45RO⁺CCR7⁺CD4⁺ T cells, and 1.24% ± 0.13% of dCD4⁺CRTH2⁺ T cells (A,C). The CD45RO⁺ memory T cells include approximately 25.14% ± 4.22% of the pCD4⁺ T cells, the CCR7⁺CD45RO⁺ Tcm are 10.75% ± 4.35%, and pCD4⁺CRTH2⁺ T cells are approximately 3.18% ± 2.42% (B-C). Cytokine production by decidual CD45RO⁺CCR7⁺CD4⁺ T cells and CD4⁺CRTH2⁺ T cells was determined by flow cytometry (D). Data are the means ± SD from 4 independently conducted experiments with 4 samples, and compared in the histogram (C-D).