Natural killer T cells in Preeclampsia: An updated review
Vida Hashemi a,b,d, Sanam Dolati a,c,d, Arezoo Hosseini a,c,d, Tohid Gharibi a,c,d, Shahla Danaiie ,Mehdi Yousefi c,d
a Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Ira
b Department of Basic Science, Faculty of Medicine, Maragheh University of Medical Sciences, Maragheh, Iran
c Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
d Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
e Gynecology Department, Eastern Azerbaijan ACECR ART Center, Eastern Azerbaijan Branch of ACECR, Tabriz, Iran
ABSTRACT
Preeclampsia (PE), as a pregnancy-specific syndrome, has become one of the main causes of maternal and fetal mortality worldwide and is known as a major risk factor for preterm birth. PE is typically characterized by hypertension, significant proteinuria, and an excessive maternal systemic inflammatory response. Recent evidences provide support for the notion that Natural killer T (NKT) cells (a small, but significant immunoregulatory T cell subset of human peripheral blood lymphocytes) play pivotal roles in pregnancy. NKT cells with unique transcriptional and cytokine profiles exist in different peripheral tissues acting as mediators between the innate and adaptive immune systems. NKT cells secrete Interleukin-4 (IL-4) and Interferon-γ (IFN-γ) which might regulate the balance between Type 1 T helper (Th1) and Type 2 T helper (Th2) responses. During pregnancy, maternal immunity is biased towards type II cytokine production to inhibit the function of type I cytokines that could be harmful for the developing fetus. This shift to type II cytokines does not occur in preeclamptic patients. In this review, we discuss the numbers, phenotype, changes, and the functional activity of Natural killer T (NKT) cells during normal pregnancy and preeclampsia