Maternal and Fetal Factors that Contribute to the Localization of T Regulatory Cells During Pregnancy

• Published in: American journal of reproductive immunology (1989) 2014-05, Vol.71 (5), p.391-400
• Main Authors: Wambach, Carrie M., Patel, Sonal N., Kahn, Daniel A.
• Format: Article
• Language: English
• Subjects: Allogeneic; Animals; Cell Movement; cervix; Cervix Uteri - cytology; Cervix Uteri - immunology; Female; Fetus - immunology; Humans; Immune Tolerance; interleukin-6; Interleukin-6 - immunology; Male; Maternal-Fetal Exchange - immunology; Mice; Mice, Inbred C57BL; Pregnancy; T regulatory; T-Lymphocytes, Regulatory - cytology; T-Lymphocytes, Regulatory - immunology; uteroplacental interface; Uterus - cytology; Uterus - immunology
• ISSN: 1046-7408; 1600-0897
• DOI: 10.1111/aji.12223

Problem To determine the interplay between fetal antigenicity and local maternal factors in determining reproductive tract T regulatory (Treg) cell accumulation during pregnancy. Method of study Examination of maternal Treg composition in the uterus, cervix, and uteroplacental interface (UPI) of murine syngeneic and allogeneic pregnancies and non‐pregnant controls by flow cytometry. The impact of fetal antigenicity was defined by either fetal gender in syngeneic pregnancies or by allogeneic paternity. Impact of IL‐6 on local Treg composition was determined using syngeneic pregnancies in IL‐6−/− females. Results An increased fraction of CD4+ T cells in the pregnant uterine lymphocytic infiltrate and draining pelvic lymph nodes are Tregs. Maternal IL‐6 decreases Treg accumulation within the uterus and to a greater extent in the cervix in syngeneic pregnancy. Fetal antigenicity is matched by accumulation of Tregs to the UPI. Treg accumulation at the UPI of non‐antigenic female fetuses is determined by the intrauterine position relative to male siblings. Conclusion Reproductive tract tissue Treg composition during pregnancy is influenced by maternal IL‐6 and fetal antigenicity.