Continuous human uterine NK cell differentiation in response to endometrial regeneration and pregnancy

• Published in: Science immunology 2021, Vol.6 (56)
• Main Authors: Strunz, Benedikt, Bister, Jonna, Jönsson, Hanna, Filipovic, Iva, Crona-Guterstam, Ylva, Kvedaraite, Egle, Sleiers, Natalie, Dumitrescu, Bogdan, Brännström, Mats, Lentini, Antonio, Reinius, Björn, Cornillet, Martin, Willinger, Tim, Gidlöf, Sebastian, Hamilton, Russell S, Ivarsson, Martin A, Björkström, Niklas K
• Format: Article
• Language: English
• Subjects: Animals; Antigens, Differentiation - genetics; Cell Differentiation - immunology; Endometrium - immunology; Endometrium - metabolism; Female; Gene Knock-In Techniques; Healthy Volunteers; Human Umbilical Vein Endothelial Cells; Humans; Immunology; Interleukin-15 - metabolism; Killer Cells, Natural - physiology; Killer Cells, Natural - transplantation; Longitudinal Studies; Lymphocyte Activation; Medicin och hälsovetenskap; Menstrual Cycle - immunology; Mice; Mice, Transgenic; Obstetrics, Gynecology and Reproductive Medicine; Pregnancy; Progesterone - metabolism; Receptors, Immunologic - genetics; Regeneration - immunology; Reproduktionsmedicin och gynekologi
• ISSN: 2470-9468; 2470-9468
• DOI: 10.1126/sciimmunol.abb7800

Immune cell differentiation is critical for adequate tissue-specific immune responses to occur. Here, we studied differentiation of human uterine natural killer cells (uNK cells). These cells reside in a tissue undergoing constant regeneration and represent the major leukocyte population at the maternal-fetal interface. However, their physiological response during the menstrual cycle and in pregnancy remains elusive. By surface proteome and transcriptome analysis as well as using humanized mice, we identify a differentiation pathway of uNK cells in vitro and in vivo with sequential acquisition of killer cell immunoglobulin-like receptors and CD39. uNK cell differentiation occurred continuously in response to the endometrial regeneration and was driven by interleukin-15. Differentiated uNK cells displayed reduced proliferative capacity and immunomodulatory function including enhanced angiogenic capacity. By studying human uterus transplantation and monozygotic twins, we found that the uNK cell niche could be replenished from circulation and that it was under genetic control. Together, our study uncovers a continuous differentiation pathway of human NK cells in the uterus that is coupled to profound functional changes in response to local tissue regeneration and pregnancy.