MDSCs in pregnancy and pregnancy-related complications: an update†.

Maternal-fetal immune tolerance is a process that involves complex interactions of the immune system, and myeloid-derived suppressor cells have emerged as one of the novel immunomodulator in the maintenance of maternal-fetal immune tolerance. Myeloid-derived suppressor cells are myeloid progenitor cells with immunosuppressive activities on both innate and adaptive cells through various mechanisms. Emerging evidence demonstrates the accumulation of myeloid-derived suppressor cells during healthy pregnancy to establish maternal-fetal immune tolerance, placentation, and fetal-growth process. By contrast, the absence or decreased myeloid-derived suppressor cells in pregnancy complications like preeclampsia, preterm birth, stillbirth, and recurrent spontaneous abortion have been reported. Here, we have summarized the origin, mechanisms, and functions of myeloid-derived suppressor cells during pregnancy along with the recent advancements in this dynamic field. We also shed light on the immunomodulatory activity of myeloid-derived suppressor cells, which can be a foundation for potential therapeutic manipulation in immunological pregnancy complications.

Meta-analysis for the relationship between circulating pregnancy-associated plasma protein A and placenta accreta spectrum.

BACKGROUND: Changes in circulating pregnancy-associated plasma protein A (PAPP-A) have been observed in women with a placenta accreta spectrum (PAS). However, no consensus has been reached according to the previous studies. Our study investigated the relationship between circulating PAPP-A and PAS risk through a systematic review and meta-analysis. METHODS: Studies comparing the circulating level of PAPP-A between pregnant women with and without PAS were obtained by searching the Medline, Cochrane Library, Embase, CNKI, and Wanfang databases from the inception of the databases until February 12, 2023. Heterogeneity was considered in the pooling of results via a random-effects model. RESULTS: Eight observational studies were obtained for the meta-analysis, which included 243 pregnant women with PAS and 1599 pregnant women without PAS. For all these women, the first-trimester circulating level of PAPP-A was measured by immunoassay and reported as multiples of the median (MoM) values. The pooled results showed that compared to those who did not develop PAS, women with PAS had significantly higher first-trimester serum level PAPP-A (mean difference: 0.43 MoM, 95% confidence interval [CI]: 0.30 to 0.56, P < .001; I2 = 32%). Furthermore, a high first-trimester serum PAPP-A level was related to a high PAS risk (odds ratio: 2.89, 95% CI: 2.13 to 3.92, P < .001; I2 = 0%). Sensitivity analysis which excluded one study at a time, also obtained similar results (p all < 0.05). CONCLUSION: Pregnant women with a high serum PAPP-A level in the first trimester may be at an increased risk for PAS.

Uterine Natural Killer Cells: A Rising Star in Human Pregnancy Regulation.

Uterine natural killer (uNK) cells are an immune subset located in the uterus. uNK cells have distinct tissue-specific characteristics compared to their counterparts in peripheral blood and lymphoid organs. Based on their location and the pregnancy status of the host, uNK cells are classified as endometrial NK (eNK) cells or decidua NK (dNK) cells. uNK cells are important in protecting the host from pathogen invasion and contribute to a series of physiological processes that affect successful pregnancy, including uterine spiral artery remodeling, fetal development, and immunity tolerance. Abnormal alterations in uNK cell numbers and/or impaired function may cause pregnancy complications, such as recurrent miscarriage, preeclampsia, or even infertility. In this review, we introduce recent advances in human uNK cell research under normal physiological or pathological conditions, and summarize their unique influences on the process of pregnancy complications or uterine diseases. Finally, we propose the potential clinical use of uNK cells as a novel cellular immunotherapeutic approach for reproductive disorders.

A case of impetigo herpetiformis in which termination of pregnancy was required.

Impetigo herpetiformis is a rare variant of generalized pustular psoriasis that occurs during pregnancy or is triggered by pregnancy, often in association with hypocalcemia. This condition is associated with increased maternal and fetal morbidity and mortality. We report a 29-year-old pregnant woman who presented to hospital at the gestational age of 20 weeks with widespread erythema covered with pustules that coalesced to form lakes of pus. She did not respond to corticosteroids, immunosuppressants, or phototherapy. Finally, intra-amniotic injection of ethacridine lactate was administered to terminate the pregnancy, and the patient showed complete recovery in 3 months. Insight from this case report may facilitate optimal management of this relatively rare entity.