Expression of dNK cells and their cytokines in twin pregnancies with preeclampsia

Role of Decidual Natural Killer Cells in the Pathogenesis of Preeclampsia

Preeclampsia is one of the most severe obstetric complications, yet its pathogenesis remains unclear. Decidual natural killer (dNK) cells, the most abundant immune cells at the maternal-fetal interface, are closely associated with preeclampsia due to abnormalities in their quantity, phenotype, and function. This review summarizes the molecular mechanisms by which dNK cells regulate extravillous trophoblast (EVT) invasion, promote uterine spiral artery remodeling, and maintain immune tolerance. Furthermore, it explores how disruptions in these mechanisms and changes in the decidual microenvironment alter dNK cell properties, driving the progression of preeclampsia. Understanding the mechanisms of dNK cells and identifying potential therapeutic targets may provide new insights for clinical intervention.

The function of decidua natural killer cells in physiology and pathology of pregnancy

The role of decidual natural killer (dNK) cells in maintaining immune tolerance at the maternal-fetal interface during pregnancy is a significant topic in reproductive health. Immune tolerance is essential for a successful pregnancy and involves a complex immune response involving various immune cells and molecules. DNK cells comprise the largest population of lymphocyte subsets found in the decidua and play important roles in maintaining immune tolerance. These cells exert multiple functions to maintain homeostasis of the decidual microenvironment, including modulation of trophoblast invasion, promotion of fetal development, regulation of endometrial decidualization and spiral artery remodeling. DNK cells can also be divided into different subsets based on their functions as NKtolerant , NKcytotoxic , and NKregulatory cells. However, the relationship between dNK cells function and pregnancy outcomes is complex and poorly understood. In this review, we will focus on the physiological role of dNK cells during pregnancy and highlight the potential role in pathological pregnancies and therapeutic approaches.

Effect of IL-15-Mediating IFN-γ on HTR-8/SVneo Cells and a Preeclampsia Mouse Model Induced by Lipopolysaccharides

OBJECTIVE

Determine the effect of interleukin (IL)-15 on HTR-8/SVneo cells and a preeclampsia (PE) mouse model induced by LPS.

METHODS

Transwell and Annexin-V-FITC/PI assays were performed in HTR-8/SVneo cells transfected with IL-15 activation plasmid/siRNA prior to LPS treatment. Additionally, pregnant mice were injected with LPS and IL-15 siRNA followed by measurement of systolic blood pressure (SBP), urine protein, and serum NO. HE staining was used to observe the morphological changes of the placenta and kidney. Glycogen accumulation was detected using Best's carmine. qRT-PCR, Western blotting, and ELISA were performed to detect mRNA and protein expression.

RESULTS

LPS increased IL-15 and IFN-γ expression in HTR-8/SVneo cells, and IL-15 positively regulated IFN-γ expression in LPS-induced HTR-8/SVneo cells. Moreover, LPS promoted apoptosis and reduced the invasion and migration of HTR-8/SVneo cells, which was, further, promoted by IL-15 overexpression but attenuated by IL-15 inhibition. Furthermore, LPS increased SBP and urine protein but decreased serum NO in mice, and these factors were reversed by IL-15 siRNA. Downregulation of IL-15 also mitigated kidney injury and improved pregnancy outcomes in LPS-induced PE mice. A significantly thicker junctional zone (JZ) and thinner labyrinth layer were found in placentas of PE mice treated with IL-15 siRNA, along with increased glycogen trophoblast cells in the JZ. Moreover, decreased IFN-γ and NKp46 were found in placentas of PE mice treated with IL-15 siRNA.

CONCLUSION

IL-15 inhibition reduced cell apoptosis and increased the invasive and migratory abilities of LPS-induced HTR-8/SVneo cells, thereby alleviating the PE-like phenotype and improving pregnancy outcome.

Preeclampsia: inflammatory signature of decidual cells in early manifestation of disease

INTRODUCTION

Preeclampsia is a pregnancy-specific complication characterized by hypertension in combination with proteinuria and/or various manifestations of multiple organ failure. It is believed that etiology of preeclampsia lies in dysfunction of the placenta and disorder of the maternal-fetal interactions. In preeclampsia decidual membrane, the maternal part of the placenta which normally supports immunological tolerance of the maternal organism to the semi-allogeneic fetus, becomes a site of inflammation.

METHODS

The aim of our study was to characterize the phenotype of decidual macrophages and plasma profiles in patients with late- and early-onset preeclampsia as compared with controls (n = 43). Decidual cells were obtained by enzymatic digestion method and characterized by flow cytometry analysis, real-time PCR, bioinformatics analysis, immunohistochemistry, and Western blot. Plasma samples were analyzed by multiplex assay.

RESULTS

The number of inflammation-associated CD86+ and CX3CR1+ cells was significantly higher in the early-onset preeclampsia while the portion of CD163+ cells was significantly higher among studied groups. We observed significant increase of endothelin-1 gene expression and a significant decrease in eNOS and GNB3 expression and TGFβ relative protein level in decidual cells of the early-onset preeclampsia samples. We also revealed elevation of pro- and anti-inflammatory cytokines in plasma of preeclampsia groups.

DISCUSSION

Our findings reflect profound early-onset preeclampsia-associated alterations in the decidua and emphasize the importance of the decidua as a link in the development of preeclampsia.