Human Cytomegalovirus Infection Elicits New Decidual Natural Killer Cell Effector Functions

PLoS Pathogens

Hicham El Costa¹  Nabila Jabrane-Ferrat¹  Alain Berrebi²  Julie Tabiasco³  Johan Siewiera⁴  Philippe Bouteiller⁴  Géraldine Cartron⁵ 

[1] UMR 1043, Toulouse, France;UMR 5282, Toulouse, France;Centre National Recherche Scientifique;Institut National de la Santé et de la Recherche Médicale;Université Toulouse III Paul Sabatier, Toulouse, France

关键词: Fibroblasts;    Cytotoxicity;    Cytomegalovirus infection;    NK cells;    Trophoblasts;    Human cytomegalovirus;    Cytokines;    Pregnancy;   

DOI  :  10.1371/journal.ppat.1003257

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

During the first trimester of pregnancy the uterus is massively infiltrated by decidual natural killer cells (dNK). These cells are not killers, but they rather provide a microenvironment that is propitious to healthy placentation. Human cytomegalovirus (HCMV) is the most common cause of intrauterine viral infections and a known cause of severe birth defects or fetal death. The rate of HCMV congenital infection is often low in the first trimester of pregnancy. The mechanisms controlling HCMV spreading during pregnancy are not yet fully revealed, but evidence indicating that the innate immune system plays a role in controlling HCMV infection in healthy adults exists. In this study, we investigated whether dNK cells could be involved in controlling viral spreading and in protecting the fetus against congenital HCMV infection. We found that freshly isolated dNK cells acquire major functional and phenotypic changes when they are exposed to HCMV-infected decidual autologous fibroblasts. Functional studies revealed that dNK cells, which are mainly cytokines and chemokines producers during normal pregnancy, become cytotoxic effectors upon their exposure to HCMV-infected autologous decidual fibroblasts. Both the NKG2D and the CD94/NKG2C or 2E activating receptors are involved in the acquired cytotoxic function. Moreover, we demonstrate that CD56pos dNK cells are able to infiltrate HCMV-infected trophoblast organ culture ex-vivo and to co-localize with infected cells in situ in HCMV-infected placenta. Taken together, our results present the first evidence suggesting the involvement of dNK cells in controlling HCMV intrauterine infection and provide insights into the mechanisms through which these cells may operate to limit the spreading of viral infection to fetal tissues.

【 授权许可】

CC BY