Anti-phospholipid antibodies and reproductive failures

Angiotensin II type-1 receptor autoantibody positively correlates with the rate of metaphase I oocytes in infertility with ovulatory disorder

The renin-angiotensin system (RAS) plays an important role in reproductive function. Our previous study identified that angiotensin II type-1 receptor autoantibody (AT1-AA), an autoantibody that activates RAS, was closely associated with infertility. However, its distribution in different types of infertility remained unclear. This study was designed to explore the distribution of AT1-AA in infertile patients and the connections between AT1-AA and oocyte development and pregnancy outcome. A total of 184 infertile women participated, with samples collected from peripheral venous blood. ELISA was used to detect AT1-AA levels in their sera. It was observed that the proportion of ovulation-disorder factors in AT1-AA-positive group was significantly higher than that in negative group (P=0.001). In 59 infertile women with ovulatory disorders, compared with negative group, AT1-AA-positive group had lower rate of retrieval (P=0.032) and metaphase II (MII) oocytes (P=0.011) but higher proportion of metaphase I (MI) oocytes (P=0.019). A negative correlation was found between the levels of AT1-AA and rate of retrieval and MII oocytes (P=0.027; P=0.043), whereas a positive correlation was observed with the proportion of MI oocytes (P=0.002). Moreover, a specific predictive value for proportion of reaching MII and MI oocytes was exhibited by AT1-AA (P < 0.01; P < 0.05). But no significant difference in embryonic parameters or pregnancy outcomes between two groups was observed (P > 0.05). This study revealed that serum AT1-AA levels were significantly increased in infertile women with ovulatory disorders and positively correlated with proportion of MI oocytes, but not associated with outcomes of assisted reproduction.

Triumph Over Adversity: A Comprehensive Case Series on Successful Pregnancy Outcomes in Antiphospholipid Antibody (APLA)-Positive Patients

The intricate relationship between antiphospholipid antibody (APLA) syndrome and pregnancy outcomes challenges the prevailing notion of inevitable reproductive complications associated with APLA. The introduction provides a comprehensive overview of APLA, its autoimmune thrombophilic nature, and its common association with adverse pregnancy outcomes, emphasizing the need for a nuanced understanding. Here we discuss five case reports to showcase diverse scenarios, each highlighting successful pregnancies in APLA-positive patients, thereby contributing valuable insights into the management of this complex condition. The cases span various clinical presentations, patient demographics, and therapeutic approaches, emphasizing the heterogeneity of APLA-positive pregnancies and the importance of personalized care. The discussion delves into the broader context of APLA's impact on pregnancy, emphasizing recurrent miscarriage and venous thromboembolism (VTE) as severe complications. It underscores the significance of pre-conceptional counseling, a multidisciplinary approach, and regular antenatal monitoring in managing APLA-positive pregnancies. The identification of commonalities among the cases provides a basis for recognizing mitigating factors that contribute to positive outcomes, offering valuable guidance for healthcare providers. The series acknowledges the existence of catastrophic antiphospholipid syndrome (CAPS) and underscores the importance of early recognition and intervention in high-risk cases. Despite the challenges posed by APLA, the cases in the series offer a ray of hope by showcasing instances of successful pregnancies, attributing positive outcomes to optimized therapeutic interventions and vigilant antenatal care. In conclusion, the case series serves as a valuable resource for healthcare professionals, researchers, and policymakers, providing a nuanced perspective on APLA-positive pregnancies. By synthesizing diverse experiences and outcomes, the series contributes to the ongoing dialogue surrounding optimal management strategies, ultimately aiming to improve the quality of care for individuals facing the unique challenges posed by APLA during their reproductive journey.

Antiphospholipid syndrome pathogenesis in 2023: an update of new mechanisms or just a reconsideration of the old ones?

Antibodies against phospholipid (aPL)-binding proteins, in particular, beta 2 glycoprotein I (β2GPI), are diagnostic/classification and pathogenic antibodies in antiphospholipid syndrome (APS). β2GPI-aPL recognize their target on endothelium and trigger a pro-thrombotic phenotype which is amplified by circulating monocytes, platelets and neutrophils. Complement activation is required as supported by the lack of aPL-mediated effects in animal models when the complement cascade is blocked. The final result is a localized clot. A strong generalized inflammatory response is associated with catastrophic APS, the clinical variant characterized by systemic thrombotic microangiopathy. A two-hit hypothesis was suggested to explain why persistent aPL are associated with acute events only when a second hit allows antibody/complement binding by modulating β2GPI tissue presentation. β2GPI/β2GPI-aPL are also responsible for obstetric APS, being the molecule physiologically present in placental/decidual tissues. Additional mechanisms mediated by aPL with different characteristics have been reported, but their diagnostic/prognostic value is still a matter of research.

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.

The role of thrombophilias in reproduction: A swot analysis

Thrombophilia is a group of inherited or acquired coagulation disorders that have been associated with reproductive failure. However, there are still no clear recommendations on whether its inclusion in the initial study of the infertile couple or patients with recurrent implantation failure is necessary. In this discussion paper, based on a SWOT (strengths, weaknesses, opportunities, threats) analysis, the different aspects of the repercussions of thrombophilia screening and treatment in reproduction are evaluated. To avoid possible subjectivity in the analysis and results of this study, researchers followed Oxford criteria for the evaluation of evidence. The results from the evaluation of the reviewed bibliography seem to indicate that, pending new evidence, it would be advisable not to include thrombophilia screening in the initial baseline study of the infertile couple. There is no evidence to support a clear association between thrombophilia and implantation failure or infertility. Thrombophilia testing in this setting may increase cost, with minimal potential benefit and lead to inappropriate use of anticoagulants with possible deleterious adverse effects. Future well-designed studies are needed to assess the possible benefit of anticoagulant therapy in infertile thrombophilic patients with implantation failure.

Epitope of antiphospholipid antibodies retrieved from peptide microarray based on R39-R43 of β2-glycoprotein I

Background

Antiphospholipid antibody (aPL) syndrome (APS) is an autoimmune disease characterized by the presence of antiphospholipid antibodies and thromboembolic or pregnancy complications. Although cryptic epitope R39-R43 belonging to beta-2-glycoprotein 1 (β2GP1) has been identified as the main antigenic determinant for aPLs, we have recently demonstrated that the epitope is a motif determined by the polarity, rather than by the sequence or charge of amino acids.

Objective

In the present study, we wanted to identify the association of residues needed to obtain the highest aPL affinity.

Methods

Based on the epitope R39-R43 and our identified motif, we generated a printed peptide microarray of 676 different peptides. These peptides have been then screened for their ability to interact with the plasmas from 11 well-characterized APS patients and confirmed by surface plasma resonance assay.

Results and Conclusions

We identified a peptide that selectively bound immunoglobulin G (IgG) derived from APS patients with 100 times more affinity than β2GP1, Domain I, or epitope R39-R43. This peptide is able to inhibit the activity of IgG derived from APS patients in vitro. We have also generated a monoclonal IgG antibody against this peptide. Using both peptide and monoclonal antibody, we have been able to develop a fully standardized indirect colorimetric immunoassay with highly sensitivity. The identification of the optimized peptide offers a new standardized and accurate tool for diagnostics of APS. Furthermore, having increased affinity for aPL, this peptide could represent a useful tool as prevention strategy for APS and an alternative to the use of anticoagulants.

Antiphospholipid antibodies and idiopathic infertility

OBJECTIVE

The aim of our study was to evaluate obstetric outcome of women affected by idiopathic infertility showing persistently positive antiphospholipid antibodies (aPL).

METHODS

: From 2000 consecutive patients undergoing ART, we selected 151 (7.55%) clinical records of patients affected by idiopathic infertility undergoing ICSI and showing positive aPL.

RESULTS

Persistently positive aPL were found in 64/151 (42.38%) of the patients: in 34/64 (53.12%) at medium/high titers (group A) and in 30/64 (46.87%) at low titers (group B). Primary or secondary antiphospholipid syndrome (APS) was diagnosed in 25% of the patients, whereas 37.5% women showed clinical and/or laboratory features suggestive of APS, but not fulfilling clinical or laboratory classification criteria. Idiopathic infertility was the sole symptom in 31.25%. In 55% of these infertile patients, a history of recurrent failures of assisted reproductive techniques (ART) was also observed. Eighty-eight percent (88.88%) of women became pregnant and 77.77% gave birth. During pregnancy, an increase of aPL values was observed in 29.41% women of group B.

CONCLUSIONS

A careful selection of patients allowed us to confirm that women affected by idiopathic infertility show a high prevalence of aPL, suggesting that these autoantibodies can also affect conception. Considering pregnancy complications and thrombotic risk related to ovarian stimulation, measuring aPL can represent a valid tool to identify among infertile women undergoing ART those at higher risk of pregnancy complications potentially life-threatening for mother and the fetus. In such patients, an accurate diagnosis and an adequate therapy are related to a better ART outcome.

Comparison of treatments for the prevention of fetal growth restriction in obstetric antiphospholipid syndrome: a systematic review and network meta-analysis

Women with criteria and non-criteria obstetric antiphospholipid syndrome (APS) carry an increased risk of pregnancy complications, including fetal growth restriction (FGR). The management of obstetric APS traditionally involves clinicians, obstetricians and gynaecologists; however, the most appropriate prophylactic treatment strategy for FGR prevention in APS is still debated. We performed a systematic review and network meta-analysis (NetMA) to summarize current evidence on pharmacological treatments for the prevention of FGR in APS. We searched PubMed and Embase from inception until July 2020, for randomized controlled trials and prospective studies on pregnant women with criteria or non-criteria obstetric APS. NetMA using a frequentist framework were conducted for the primary outcome (FGR) and for secondary outcomes (fetal or neonatal death and preterm birth). Adverse events were narratively summarised. Out of 1124 citations, we included eight studies on 395 pregnant patients with obstetric APS treated with low-dose aspirin (LDA) + unfractionated heparin (UFH) (n = 132 patients), LDA (n = 115), LDA + low molecular weight heparin (n = 100), LDA + corticosteroids (n = 29), LDA + UFH + intravenous immunoglobulin (n = 7), or untreated (n = 12). No difference among treatments emerged in terms of FGR prevention, but estimates were largely imprecise, and most studies were at high/unclear risk of bias. An increased risk of fetal or neonatal death was found for LDA monotherapy as compared to LDA + heparin, and for no treatment as compared to LDA + corticosteroids. The risk of preterm birth was higher for LDA + UFH + IVIg as compared to LDA or LDA + heparin, and for LDA + corticosteroids as compared to LDA or LDA + LMWH. No treatment was associated with an increased risk of bleeding, thrombocytopenia or osteopenia.

Pediatric Antiphospholipid Syndrome: from Pathogenesis to Clinical Management

PURPOSE OF REVIEW

Elucidating the pathogenic mechanisms mediated by antiphospholipid antibodies (aPL) might exert important clinical implications in pediatric antiphospholipid syndrome (APS).

RECENT FINDINGS

aPL are traditionally regarded as the main pathogenic players in APS, inducing thrombosis via the interaction with fluid-phase and cellular components of coagulation. Recent APS research has focused on the role of β2 glycoprotein I, which bridges innate immunity and coagulation. In pediatric populations, aPL should be screened in appropriate clinical settings, such as thrombosis, multiple-organ dysfunction, or concomitant systemic autoimmune diseases. Children positive for aPL tests often present non-thrombotic non-criteria manifestations or asymptomatic aPL positivity. In utero aPL exposure has been suggested to result in developmental disabilities, warranting long-term follow-up. The knowledge of the multifaceted nature of pediatric APS should be implemented to reduce the risk of underdiagnosing/undertreating this condition. Hopefully, recent pathogenic insights will open new windows of opportunity in the management of pediatric APS.

The Weight of IgA Anti-β2glycoprotein I in the Antiphospholipid Syndrome Pathogenesis: Closing the Gap of Seronegative Antiphospholipid Syndrome

The specific value of IgA Anti-β2glycoprotein I antibodies (aB2GP1) in the diagnosis and management of antiphospholipid syndrome (APS) is still controversial and a matter of active debate. The relevance of the IgA aB2GP1 isotype in the pathophysiology of APS has been increasingly studied in the last years. There is well know that subjects with multiple positive APS tests are at increased risk of thrombosis and/or miscarriage. However, these antibodies are not included in the 2006 APS classification criteria. Since 2010 the task force of the Galveston International Congress on APS recommends testing IgA aB2GP1 isotype in patients with APS clinical criteria in the absence of criteria antibodies. In this review, we summarize the molecular and clinical “state of the art” of the IgA aB2GP in the context of APS. We also discuss some of the characteristics that may help to evaluate the real value of the IgA aB2GP1 determination in basic research and clinical practice. The scientific community should be aware of the importance of clarifying the role of IgA aB2GP1 in the APS diagnosis.