Antinuclear antibodies in patients with endometriosis: A cross-sectional study in 94 patients

Reproductive Effect by Rheumatoid Arthritis and Related Autoantibodies

Rheumatoid arthritis (RA) is a common inflammatory arthritis in women. The effects of RA on the reproductive system are usually overlooked, as RA is not diagnosed until later in reproductive age. Whether RA itself or its related rheumatoid antibodies have an impact on female reproductive function has long been a thought-provoking issue. In brief, relevant epidemiological evidence has shown that women affected by RA are more likely to have coexisting reproductive disorders, including infertility, endometriosis, and premature ovarian insufficiency (POI), or to subsequently develop them. Furthermore, linkage between RA and pregnancy loss (PL) as well as polycystic ovary syndrome (PCOS) is also well known, albeit controversial in available evidence. RA and reproductive disorders appear to share a similar inflammatory immune response and genetic background. The stress experienced by patients with RA may affect their reproductive choices to some extent. Notably, few studies have explored the impact of rheumatoid antibodies such as rheumatoid factors (RFs) and anti-citrullinated protein antibodies (ACPAs) on reproductive disorders. Although it has been mentioned that the rate of RF and/or ACPA positivity is higher in women with a history of PL and POI, the clinical relevance of this relationship and underlying mechanisms still need to be further clarified.

Understanding endometriosis from an immunomicroenvironmental perspective

ABSTRACT

Endometriosis, a heterogeneous, inflammatory, and estrogen-dependent gynecological disease defined by the presence and growth of endometrial tissues outside the lining of the uterus, affects approximately 5-10% of reproductive-age women, causing chronic pelvic pain and reduced fertility. Although the etiology of endometriosis is still elusive, emerging evidence supports the idea that immune dysregulation can promote the survival and growth of retrograde endometrial debris. Peritoneal macrophages and natural killer (NK) cells exhibit deficient cytotoxicity in the endometriotic microenvironment, leading to inefficient eradication of refluxed endometrial fragments. In addition, the imbalance of T-cell subtypes results in aberrant cytokine production and chronic inflammation, which contribute to endometriosis development. Although it remains uncertain whether immune dysregulation represents an initial cause or merely a secondary enhancer of endometriosis, therapies targeting altered immune pathways exhibit satisfactory effects in preventing disease onset and progression. Here, we summarize the phenotypic and functional alterations of immune cells in the endometriotic microenvironment, focusing on their interactions with microbiota and endocrine and nervous systems, and how these interactions contribute to the etiology and symptomology of endometriosis.

Hydroxychloroquine improves pregnancy outcomes in patients undergoing frozen embryo transfer with positive serum autoantibodies

PROBLEM

Does hydroxychloroquine (HCQ) improve pregnancy outcomes after frozen embryo transfer (FET) cycles in patients who are positive for autoantibodies？ METHOD OF STUDY: This was a retrospective clinical study involving 128 patients who were positive for autoantibodies undergoing FET cycles between October 2017 and December 2022. Subjects were divided into two groups: a study group of 65 cycles with HCQ (HCQ was administered orally over 2 months before transplantation and continued during the first trimester) and a control group consisting of 63 cycles without HCQ (no HCQ was used throughout the FET cycle). Each patient was enrolled in the cohort only once. Then, we analyzed the clinical pregnancy outcomes between the two groups.

RESULTS

Analysis showed that HCQ was a factor that independently associated with clinical pregnancy rate (CPR) OR (Odds Ratio): 3.106; 95% confidence interval (CI): 1.458-6.616; p = .003. Furthermore, the implantation rate (IR), CPR and ongoing pregnancy rate (OPR) of the treatment group were significantly higher than those in the control group. The biochemical pregnancy rate (BPR) and early miscarriage rate (EMR) were significantly lower than that in the control group (p = .029, p < .001).

CONCLUSION

We found that HCQ improved clinical pregnancy outcomes and reduced the rate of first-trimester abortion in patients who were positive for autoantibodies during FET cycles.

Pyroptosis orchestrates immune responses in endometriosis

Endometriosis is a refractory and recurrent gynecological condition which affects about 10 % of reproductive-age women. The dysfunctional immune system is a well-established element in disease pathogenesis. Pyroptosis, a novel form of inflammatory cell death, has been revealed to be strongly connected with immune responses in tumors. Nevertheless, its relationship with microenvironment characteristics and clinical features in endometriosis is unclear. Here, we performed bioinformatics analysis on published data in humans and revealed a significant but neglected role of pyroptosis in endometriosis. Samples with higher PyrScores were generally accompanied with more aggressive disease features, such as EMT, angiogenesis and immune disorders. We further confirmed in animal models that pyroptosis exacerbated immune dysfunction by recruiting activated immune cell including macrophages, DC, neutrophils, CD8+ Tcm and Tregs with unregulated CCL2, CCL3, CXCL2 and CXCL3. Collectively, pyroptosis is a distinctive feature of endometriosis. Our work provides insights into further studies targeting pyroptosis for molecular typing and individualized precise therapy.

Serological autoimmune profile of systemic lupus erythematosus in deep and non-deep endometriosis patients

OBJECTIVE

Several studies have reported a high prevalence of autoimmune diseases such as systemic lupus erythematosus (SLE) in endometriosis patients. The aim of this study was to evaluate the SLE autoimmune antibody profile in patients with deep (DE) and non-deep endometriosis (Non-DE).

MATERIALS AND METHODS

Four groups of premenopausal patients were evaluated: patients with DE (n = 50); patients with ovarian endometriomas (Non-DE; n = 50); healthy patients without endometriosis (C group; n = 45); and SLE patients without endometriosis (SLE group; N = 46). Blood samples were obtained and the standard SLE autoimmune profile was evaluated in all patients. Pain symptoms related to endometriosis and clinical SLE manifestations were also recorded.

RESULTS

The DE group presented a statistically significant higher proportion of patients with antinuclear antibodies (ANA) (20%) compared to the Non-DE group (4%) and C group (2.2%). Levels of complement were more frequently lower among DE and Non-DE patients although differences did not reach statistical significance. Similarly, anti-dsDNA antibodies and anticoagulant lupus were positive in more patients of the DE group but did not reach statistical significance. The DE group complained of more arthralgia and asthenia compared to the Non-DE and C groups.

CONCLUSIONS

The results of this study showed higher positivity of ANA and greater arthralgia and asthenia in patients with DE compared with Non-DE patients and healthy controls, suggesting that they may have a higher susceptibility to autoimmune diseases and present more generalized pain.

Peripheral blood subpopulations of Bregs producing IL-35 in women with endometriosis

PROBLEM

Interleukin 35 (IL-35) is involved in the pathogenesis of endometriosis by suppressing immunoreaction and promoting endometrial cell proliferation. It may also be an essential cytokine in forming the immunosuppressive functions of regulatory B lymphocytes (Bregs). The involvement of Bregs in the pathogenesis of endometriosis has not been previously investigated. In this study, we determined the frequencies of different Breg subpopulations, namely, B10, immature B-cells, and plasmablasts, and their abilities to produce IL-35 in women with endometriosis compared to healthy women.

METHODS

The frequencies of different subpopulations of Bregs producing IL-35 were measured in the peripheral blood of women with endometriosis (total pool), women with deep infiltration endometriosis (DIE), women with ovarian endometriosis, and healthy women as a control by flow cytometry.

RESULTS

We observed a decrease in the percentage of B10 cells and plasmablasts in women with endometriosis and an increase in the percentage of these Breg populations producing IL-35 in the same experimental group. Interestingly, we also revealed that women with DIE had increased percentages of B10 cells and plasmablasts producing IL-35.

CONCLUSION

Taken together, our findings are the first to reveal the frequencies of different subpopulations of Bregs producing IL-35 in women with endometriosis. The results suggest that IL-35 expression in B lymphocytes could be used as a peripheral marker of endometriosis; however, further studies are needed.

Autoantibody screening of plasma and peritoneal fluid of patients with endometriosis

STUDY QUESTION

Are there specific autoantibody profiles in patients with endometriosis that are different from those in controls?

SUMMARY ANSWER

This study did not reveal a significantly higher prevalence of autoantibodies in the studied groups of patients.

WHAT IS KNOWN ALREADY

Various inflammatory factors are postulated to be involved in the pathomechanisms of endometriosis, and a potential link exists with autoimmune diseases, which may also play an important role. As the diagnosis of endometriosis remains invasive, it can only be confirmed using laparoscopy with histopathological examination of tissues. Numerous studies have focused on identifying useful biomarkers to confirm the disease, but without unequivocal effects. Autoantibodies are promising molecules that serve as potential prognostic factors.

STUDY DESIGN, SIZE, DURATION

A multicentre, cross-sectional study was conducted over 18 months (between 2018 and 2019), at eight Departments of Obstetrics and Gynaecology in several cities across Poland on 137 patients undergoing laparoscopic examination for the diagnosis of endometriosis.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

During laparoscopy, we obtained plasma samples from 137 patients and peritoneal fluid (PF) samples from 98 patients. Patients with autoimmune diseases were excluded from the study. Autoantibody profiling was performed using HuProt v3.1 human proteome microarrays.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed no significant differences in the expression of autoantibodies in the plasma or PF between the endometriosis and control groups. The study revealed that in the PF of women with Stage II endometriosis, compared with other stages, there were significantly higher reactivity signals for ANAPC15 and GABPB1 (adj. P < 0.016 and adj. P < 0.026, respectively; logFC > 1 in both cases). Comparison of the luteal and follicular phases in endometriosis patients revealed that levels of NEIL1 (adj. P < 0.029), MAGEB4 (adj. P < 0.029), and TNIP2 (adj. P < 0.042) autoantibody signals were significantly higher in the luteal phase than in the follicular phase in PF samples of patients with endometriosis. No differences were observed between the two phases of the cycle in plasma or between women with endometriosis and controls. Clustering of PF and plasma samples did not reveal unique autoantibody profiles for endometriosis; however, comparison of PF and plasma in the same patient showed a high degree of concordance.

LIMITATIONS, REASONS FOR CAUTION

Although this study was performed using the highest-throughput protein array available, it does not cover the entire human proteome and cannot be used to study potentially promising post-translational modifications. Autoantibody levels depend on numerous factors, such as infections; therefore the autoantibody tests should be repeated for more objective results.

WIDER IMPLICATIONS OF THE FINDINGS

Although endometriosis has been linked to different autoimmune diseases, it is unlikely that autoimmune responses mediated by specific autoantibodies play a pivotal role in the pathogenesis of this inflammatory disease. Our study shows that in searching for biomarkers of endometriosis, it may be more efficient to use higher-throughput proteomic microarrays, which may allow the detection of potentially new biomarkers. Only research on such a scale, and possibly with different technologies, can help discover biomarkers that will change the method of endometriosis diagnosis.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by a grant from the Polish Ministry of Health (grant no. 6/6/4/1/NPZ/2017/1210/1352). It was also funded by the Estonian Research Council (grant PRG1076) and the Horizon 2020 Innovation Grant (ERIN; grant no. EU952516), Enterprise Estonia (grant no. EU48695), and MSCA-RISE-2020 project TRENDO (grant no. 101008193). The authors declare that there is no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

The histopathological features of the surgical endometriosis model using systemic autoimmune disease-prone mice

Endometriosis is a common gynecological disease that affects women of reproductive age in which the uterine endometrium grows outside the uterus. Origin of the ectopic endometrium is thought to be the retrograde endometrium through the oviducts. However, factors that determine the adherence and proliferation of the ectopic endometrium have not been revealed. Importantly, systemic autoimmune diseases are considered a key factor in the endometriosis onset. Herein, we established a surgical endometriosis rodent model using autoimmune disease-prone MRL/MpJ-Faslpr/lpr (MRL/lpr) and MRL/+ mice to provide basic evidence of the relationship between autoimmune disease and endometriosis. Endometriosis lesions were successfully induced in two regions after transplanting uterine tissues from donor mice into the peritoneal cavity of recipient mice: the peritoneum or adipose tissue around the transplantation point (proximal lesions) and the gastrosplenic ligament or intestinal mesentery far from the transplantation site (distal lesions). Distal lesions were observed only in MRL/lpr mice, whereas endometriosis lesions showed no genotype- or region-related differences in the histology and distribution of sex hormone receptors and T cells. In contrast, transplanted uterine tissues in donor MRL/lpr mice exhibited a large infiltration of T cells in the lamina propria. Splenomegaly was more common in recipient than that in donor MRL/lpr mice. These results suggest that the infiltration of endogenous T cells in the endometrium alters the growth features of ectopic endometrium, possibly affecting the severity of endometriosis in patients with systemic autoimmune diseases.