%A Chen,Pengfei %A Zhou,Liying %A Chen,Jiying %A Lu,Ying %A Cao,Chaoxia %A Lv,Shuangli %A Wei,Zhihong %A Wang,Liping %A Chen,Jiao %A Hu,Xinglin %A Wu,Zijing %A Zhou,Xiaohua %A Su,Danna %A Deng,Xuefeng %A Zeng,Changchun %A Wang,Huiyun %A Pu,Zuhui %A Diao,Ruiying %A Mou,Lisha %D 2021 %J Frontiers in Immunology %C %F %G English %K unexplained recurrent pregnancy loss,Human decidua,immune heterogeneity,single-cell RNA sequencing,decidual natural killer cell,ScRNA,the immune atlas %Q %R 10.3389/fimmu.2021.689019 %W %L %M %P %7 %8 2021-June-07 %9 Original Research %+ Zuhui Pu,Department of Radiology, First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital,China,lishamou@email.szu.edu.cn %+ Ruiying Diao,Centre of Reproductive Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital,China,lishamou@email.szu.edu.cn %+ Lisha Mou,Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital,China,lishamou@email.szu.edu.cn %# %! Unexplained recurrent pregnancy loss %* %< %T The Immune Atlas of Human Deciduas With Unexplained Recurrent Pregnancy Loss %U https://www.frontiersin.org/articles/10.3389/fimmu.2021.689019 %V 12 %0 JOURNAL ARTICLE %@ 1664-3224 %X Recurrent pregnancy loss (RPL) is a common fertility problem that affects 1%-2% of couples all over the world. Despite exciting discoveries regarding the important roles of the decidual natural killer cell (dNK) and regulatory T cell in pregnancy, the immune heterogeneity in patients with unexplained recurrent pregnancy loss (URPL) remains elusive. Here, we profiled the transcriptomes of 13,953 CD45+ cells from three normal and three URPL deciduas. Based on our data, the cellular composition revealed three major populations of immune cells including dNK cell, T cell, and macrophage, and four minor populations including monocytes, dendritic cell (DC), mast cell, and B cell. Especially, we identified a subpopulation of CSF1+ CD59+ KIRs-expressing dNK cells in normal deciduas, while the proportion of this subpopulation was decreased in URPL deciduas. We also identified a small subpopulation of activated dDCs that were accumulated mainly in URPL deciduas. Furthermore, our data revealed that in decidua at early pregnancy, CD8+ T cells exhibited cytotoxic properties. The decidual macrophages expressed high levels of both M1 and M2 feature genes, which made them unique to the conventional M1/M2 classification. Our single-cell data revealed the immune heterogeneity in decidua and the potentially pathogenic immune variations in URPL.