The role of lymphocytic cells in infertility and reproductive failures in women with antiphospholipid antibodies

An update on the endocrine manifestations of antiphospholipid syndrome

Antiphospholipid Syndrome (APS), characterized by hypercoagulability and pregnancy morbidity, poses a significant clinical challenge when involving organ systems, such as the endocrine system. APS can directly and indirectly influence the anterior and posterior lobes of the pituitary gland. The thyroid gland exhibits involvement, especially in patients with positive anticardiolipin antibodies, yet the clinical significance of the relationship with APS remains elusive. The pancreas, often overlooked, manifests in diverse ways, from pancreatitis to implications in diabetes. Adrenal insufficiency emerges as a common endocrine manifestation of APS, with adrenal hemorrhage or infarction being a presenting manifestation. Adrenal gland involvement has also been reported in the context of catastrophic APS. Pregnancy complications and infertility might be effects of APS on the female ovaries, while testicular torsion and decreased sperm concentration and total sperm count have been reported as rare effects of APS on male testes.

Inflammatory markers are associated with infertility prevalence: a cross-sectional analysis of the NHANES 2013-2020

BACKGROUND

Inflammation exerts a critical role in the pathogenesis of infertility. The relationship between inflammatory parameters from peripheral blood and infertility remains unclear. Aim of this study was to investigate the association between inflammatory markers and infertility among women of reproductive age in the United States.

METHODS

Women aged 20-45 were included from the National Health and Nutrition Examination Survey (NHANES) 2013-2020 for the present cross-sectional study. Data of reproductive status was collected from the Reproductive Health Questionnaire. Six inflammatory markers, systemic immune inflammation index (SII), lymphocyte count (LC), product of platelet and neutrophil count (PPN), platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR) and lymphocyte-monocyte ratio (LMR) were calculated from complete blood counts in mobile examination center. Survey-weighted multivariable logistic regression was employed to assess the association between inflammatory markers and infertility in four different models, then restricted cubic spline (RCS) plot was used to explore non-linearity association between inflammatory markers and infertility. Subgroup analyses were performed to further clarify effects of other covariates on association between inflammatory markers and infertility.

RESULTS

A total of 3,105 women aged 20-45 was included in the final analysis, with 431 (13.88%) self-reported infertility. A negative association was found between log2-SII, log2-PLR and infertility, with an OR of 0.95 (95% CI: 0.78,1.15; p = 0.60), 0.80 (95% CI:0.60,1.05; p = 0.10), respectively. The results were similar in model 1, model 2, and model 3. Compared with the lowest quartile (Q1), the third quartile (Q3) of log2-SII was negatively correlation with infertility, with an OR (95% CI) of 0.56 (95% CI: 0.37,0.85; p = 0.01) in model 3. Similarly, the third quartile (Q3) of log2-PLR was negatively correlation with infertility, with an OR (95% CI) of 0.61 (95% CI: 0.43,0.88; p = 0.01) in model 3. No significant association was observed between log2-LC, log2-PPN, log2-NLR, log2-LMR and infertility in model 3. A similar U-shaped relationship between log2-SII and infertility was found (p for non-linear < 0.05). The results of subgroup analyses revealed that associations between the third quartile (Q3) of log2-SII, log2-PLR and infertility were nearly consistent.

CONCLUSION

The findings showed that SII and PLR were negatively associated with infertility. Further studies are needed to explore their association better and the underlying mechanisms.

Energy metabolism and maternal-fetal tolerance working in decidualization

One pivotal aspect of early pregnancy is decidualization. The decidualization process includes two components: the differentiation of endometrial stromal cells to decidual stromal cells (DSCs), as well as the recruitment and education of decidual immune cells (DICs). At the maternal-fetal interface, stromal cells undergo morphological and phenotypic changes and interact with trophoblasts and DICs to provide an appropriate decidual bed and tolerogenic immune environment to maintain the survival of the semi-allogeneic fetus without causing immunological rejection. Despite classic endocrine mechanism by 17 β-estradiol and progesterone, metabolic regulations do take part in this process according to recent studies. And based on our previous research in maternal-fetal crosstalk, in this review, we elaborate mechanisms of decidualization, with a special focus on DSC profiles from aspects of metabolism and maternal-fetal tolerance to provide some new insights into endometrial decidualization in early pregnancy.

The Role of Immune Cells in Recurrent Spontaneous Abortion

Recurrent spontaneous abortion affects approximately 1–2% of women of childbearing, and describes a condition in which women suffer from three or more continuous spontaneous miscarriages. However, the origin of recurrent spontaneous abortion (RSA) remains unknown, preventing effective treatment and placing stress upon patients. It has been acknowledged that successful pregnancy necessitates balanced immune responses. Therefore, immunological aberrancy may be considered a root cause of poor pregnancy outcomes. Considerable published studies have investigated the relationship between various immune cells and RSA. Here, we review current knowledge on this area, and discuss the five main categories of immune cells involved in RSA; these include innate lymphocytes (ILC), macrophages, decidual dendritic cells (DCs), and T cells. Furthermore, we sought to summarize the impact of the multiple interactions of various immune cells on the emergence of RSA. A good understanding of pregnancy-induced immunological alterations could reveal new therapeutic strategies for favorable pregnancy outcomes.

Anti-phospholipid antibody may reduce endometrial receptivity during the window of embryo implantation

BACKGROUND

Anti-phospholipid antibodies (aPL) have been reported to be associated with repeated implantation failure (RIF), but the mechanism remains controversial. Endometrial receptivity is well known to be crucial for embryo implantation. This study aims to investigate the effect of aPL on endometrial receptivity in RIF women with positive aPL.

METHODS

Sixty-four infertile women with normal menstrual cycles were enrolled. The control group comprised 32 pregnant women with negative aPL who conceived successfully after their first in vitro fertilization-embryo transfer (IVF-ET) cycle, and the RIF group comprised 32 women with positive aPL. Endometrial biopsy samples were collected seven days after the luteinizing hormone surge (LH + 7). The expression of LIF and HOXA10 was evaluated by immunohistochemistry, qRT-PCR and Western blot. Endometrial pinopode development was examined by scanning electron microscopy.

RESULTS

The mRNA expression of LIF and HOXA10 in the RIF group was significantly decreased compared with that in the control group during the implantation window. The immunohistochemistry and Western blot results confirmed these findings. Then, ultrastructural analyses of endometrial cells showed fewer pinopode processes, a more atypical morphology and increased atrophy in the RIF group compared with the control group, and these results were statistically significant.

CONCLUSION

aPL positivity may inhibit the expression of LIF and HOXA10 in the endometrium and influence pinopode development. Our findings suggest that positivity for aPL is associated with impaired endometrial receptivity, which results in the development of RIF.