Phenotypic characterization of NKT-like cells and evaluation of specifically related cytokines for the prediction of unexplained recurrent miscarriage

A preliminary study unveils CISD2 as a ferroptosis-related therapeutic target for recurrent spontaneous abortion through immunological analysis and two-sample mendelian randomization

Recurrent spontaneous abortion (RSA) affects approximately 1 % of women striving for conception, posing a significant clinical challenge. This study aimed to identify a prognostic signature in RSA and elucidate its molecular mechanisms. Prognostic gene impacts were further assessed in HTR-8/SVneo and human primary extravillous trophoblast (EVT) cells in vitro experiments. A total of 6168 differentially expressed genes (DEGs) were identified, including 3035 upregulated and 3133 downregulated genes. WGCNA pinpointed 8 significant modules and 31 ferroptosis-related DEGs in RSA. Optimal clustering classified RSA patients into three distinct subgroups, showing notable differences in immune cell composition. Six feature genes (AEBP2, CISD2, PML, RGS4, SRSF9, STK11) were identified. The diagnostic model showed high predictive capabilities (AUC: 0.966). Mendelian randomization indicated a significant association between CISD2 levels and RSA (OR: 1.069, P-value: 0.049). Furthermore, the downregulation of CISD2 promotes ferroptosis in HTR-8/SVneo and human primary EVT cells. CISD2 emerged as a pivotal gene in RSA, serving as a ferroptosis-related therapeutic target. The diagnostic model based on gene expression and Mendelian randomization provides novel insights into the pathogenesis of RSA.

Baicalin ameliorates deficient decidualization in URSA by regulating mitochondrial fission induced necroptosis

Unexplained recurrent spontaneous abortion (URSA) is a common complication of pregnancy that affects the health of pregnant women. Deficient endometrial decidualization has been associated with URSA. However, the underlying mechanism is poorly understood. This study aims to explore the mechanisms of mitochondrial fission induced necroptosis in deficient decidualization in URSA, and explore the regulation of baicalin on this mechanism. Initially, decidual tissues were collected from patients with URSA and health controls. Subsequently, in vitro induced decidualization model of Telomerase-Immortalized Human Endometrial Stromal Cells (T-hESCs) was constructed. Additionally, murine models of URSA (CBA/J × DBA/2) and normal pregnancy (CBA/J × BALB/c) were established, respectively. The level of decidualization, necroptosis, and mitochondrial fission of decidual tissues from clinical samples were detected. The function of mitochondrial fission on necroptosis during decidualization in T-hESCs was assessed by enhancing or inhibiting mitochondrial fission or necroptosis. Finally, CBA/J × DBA/2 pregnant mice were administrated with different doses of baicalin or saline, and the expression of mitochondrial fission, necroptosis, and decidualization markers were verified. The results of the study demonstrated a significant decrease in decidualization markers in the decidual tissues of URSA patients (P < 0.05), along with an increase in the incidence of cell necroptosis (P < 0.05) and hyperactive mitochondrial fission (P < 0.05). In vitro experiments, LPS was induced to trigger necroptosis of T-hESCs during induced decidualization, and decidualization markers IGFBP1 and PRL were subsequently decreased (P < 0.05). Besides, the mitochondrial fission agonist Tyrphostin A9 was found to promote the level of necroptosis (P < 0.05) and induced deficient decidualization (P < 0.05), which could be rescued by mitochondrial fission inhibitor Mdivi-1 and necroptosis inhibitor Nec-1 (P < 0.05). In addition, baicalin was shown to reduce hyperactive mitochondrial fission (P < 0.05), necroptosis (P < 0.05) and ameliorate deficient decidualization in vitro and in URSA murine models (P < 0.05). Collectively, baicalin shows potential in ameliorating deficient decidualization in URSA by inhibiting mitochondrial fission-triggered necroptosis.

Subchorionic hematoma: Research status and pathogenesis (Review)

Subchorionic hematoma (SCH) is a hematoma in which blood accumulates between the chorion and decidua basalis due to the separation of the chorion and decidua basalis. It is common in patients with threatened abortion in early pregnancy and is mainly detected by ultrasound. SCH mainly manifests as an hypoechoic or anechoic crescent-shaped fluid dark area on ultrasound images. Although there are numerous studies on SCH, its pathogenesis and etiology remain unclear, and its influence on pregnancy outcomes is also controversial; there are also no uniform clinical treatment guidelines. Current studies suggest that the occurrence of SCH may be related to several factors, such as abnormal coagulation function, autoimmune factors of pregnant women, assisted reproduction, drug use during pregnancy and reproductive tract infection; however, its exact etiology remains unclear. Some studies suggest that SCH is associated with adverse pregnancy outcomes such as miscarriage, preterm birth, preeclampsia and fetal growth restriction, although other studies have found that SCH does not increase the risk of adverse pregnancy outcomes. Therefore, the present review mainly discusses the pathogenesis, etiology and treatment of SCH in an aim to provide a reference for the clinical treatment of this condition in pregnant women.

Leptin regulates thymic plasmacytoid dendritic cell ability to influence the thymocyte distribution in vitro

Leptin, the adipocyte-derived hormone, involved in regulating food intake and body weight, plays an important role in immunity and reproduction. Leptin signals via the specific membrane receptors expressed in most types of immune cells including dendritic cells (DCs) and thymocytes. Leptin enhances thymopoiesis and modulates T-cell-mediated immunity. Thymic plasmacytoid DCs (pDCs) are predominated in the thymus. They play an important role in thymocyte differentiation. We have analyzed whether leptin mediates its effects on human thymocytes by influencing on pDCs. We used leptin at concentration corresponding to its level during II-III trimesters of physiological pregnancy. We cultivated leptin-primed pDCs with autologous thymocytes and estimated the main thymocyte subsets expressing αβ chains of the T-cell receptor (αβTCR), natural regulatory T-cells (tTreg), natural T-helpers producing interleukin-17 (nTh17) and invariant natural killer T-cells (iNKT) in vitro. We have shown that leptin augmented CD86, CD276 expressions and depressed IL-10 productions by pDCs. Leptin-primed pDCs decreased the percentage of CD4⁺CD8⁺αβTCR⁺ thymocytes, increased CD4^hiCD8^-/loαβTCR⁺ cells. pDCs cultivated with leptin decreased the number of iNKT precursors, and did not change the number of tTreg and nTh17 precursors. Thus, leptin's important role in regulation of thymic pDC abilities to influence on the thymocyte distribution was indicated in vitro.

Natural Killer T-like Cells: Immunobiology and Role in Disease

CD56+ T cells are generally recognized as a distinct population of T cells and are categorized as NKT-like cells. Although our understanding of NKT-like cells is far from satisfactory, it has been shown that aging and a number of disease situations have impacted these cells. To construct an overview of what is currently known, we reviewed the literature on human NKT-like cells. NKT-like cells are highly differentiated T cells with "CD1d-independent" antigen recognition and MHC-unrestricted cell killing. The genesis of NKT-like cells is unclear; however, it is proposed that the acquisition of innate characteristics by T cells could represent a remodeling process leading to successful aging. Additionally, it has been shown that NKT-like cells may play a significant role in several pathological conditions, making it necessary to comprehend whether these cells might function as prognostic markers. The quantification and characterization of these cells might serve as a cutting-edge indicator of individual immune health. Additionally, exploring the mechanisms that can control their killing activity in different contexts may therefore result in innovative therapeutic alternatives in a wide range of disease settings.

The peripheral and decidual immune cell profiles in women with recurrent pregnancy loss

Recurrent pregnancy loss (RPL) affects 1-2% of couples of reproductive age. Immunological analysis of the immune status in RPL patients might contribute to the diagnosis and treatment of RPL. However, the exact immune cell composition in RPL patients is still unclear. Here, we used flow cytometry to investigate the immune cell profiles of peripheral blood and decidual tissue of women who experienced RPL. We divided peripheral immune cells into 14 major subgroups, and the percentages of T, natural killer T (NKT)-like and B cells in peripheral blood were increased in RPL patients. The decidual immune cells were classified into 14 major subpopulations and the percentages of decidual T, NKT-like cells and CD11c^hi Mφ were increased, while those of CD56^hi decidual NK cells and CD11c^lo Mφ were decreased in RPL patients. The spearmen correlation analysis showed that the proportion of peripheral and decidual immune cells did not show significant correlations with occurrences of previous miscarriages. By using flow cytometry, we depicted the global peripheral and decidual immune landscape in RPL patients. The abnormalities of peripheral and decidual immune cells may be involved in RPL, but the correlations with the number of previous miscarriages need further verification.