Evaluation of the clinical relevance of anti-annexin-A5 antibodies in Chinese patients with antiphospholipid syndrome

Anti-annexin A4 antibody as a biomarker for desquamative interstitial pneumonia

Desquamative interstitial pneumonia (DIP), a rare type of idiopathic interstitial pneumonia (IIP), is smoking-related. However, some cases of DIP can also occur in non-smokers with autoimmune disorders. The diagnosis of DIP requires an invasive surgical lung biopsy, therefore, identifying a non-invasive diagnostic biomarker for DIP is crucial. This study aimed to elucidate autoantibodies specific for DIP and evaluate their diagnostic utility. Autoantibodies in the sera of patients with DIP were screened using immunoprecipitation. The common proteins recognized by autoantibodies in patients with DIP were identified using mass spectrometry and enzyme-linked immunosorbent assay (ELISA), and compared to other types of interstitial lung diseases (ILD) and pulmonary diseases. Several characteristic proteins commonly recognized by the sera of patients with DIP were revealed using immunoprecipitation and these proteins were identified as annexin A (ANXA) proteins using mass spectrometry. Using ELISA, autoantibodies to several ANXA were detected more frequently and specifically in DIP compared with those with other types of ILDs and pulmonary diseases. In particular, anti-ANXA4 antibodies had a sensitivity of 52.6 % and specificity of 99 % for DIP compared with those of other types of ILD. Therefore, anti-ANXAs antibodies, especially anti-ANXA4, could be a candidate diagnostic biomarker for DIP.

Association of Anti-Annexin A5 Antibody With Pregnancy Outcomes: A Cohort Study: Anti-annexin A5 antibody with pregnancy outcomes

OBJECTIVE

This study aims to evaluate the correlation between anti-annexin A5 (aANXA5) antibody in the blood and pregnancy outcomes .

METHODS

This study is a retrospective cohort study based on singleton pregnancies of the Third Affiliated Hospital of Wenzhou Medical University from May 2018 to December 2022. Baseline characteristics were collected from all participants. Logistic regression and interaction effect analyses were utilized to examine the risk impact of aANXA5 on pregnancy complications, adjusting for age, BMI, abortion, ANA, and aCL. Restricted cubic spline (RCS) and threshold effect analysis were applied to explore the relationship between aANXA5 levels and preterm birth (PTB), as well as pregnancy-induced hypertension (PIH).

RESULTS

The study included 501 participants, with 51 (10.2%) testing positive for aANXA5 and 450 (89.8%) testing negative. The aANXA5 positive group exhibited higher rates of ANA and antibodies to thyroglobulin (TGAb), along with increased incidences of PTB and PIH. Positive aANXA5 status was independently linked to an elevated risk of PTB (OR: 2.53, 95% CI: 1.30-4.94) and PIH (OR: 4.23, 95% CI: 1.54-11.62). Subsequent subgroup analysis indicated no significant interaction between the groups (p > 0.05). Threshold analysis revealed that the OR for PTB was 1.20 (95% CI: 1.03-1.39) in participants with aANXA5 levels ≥ 32.77 ng/mL, and the OR for PIH was 1.62 (95% CI: 1.15-2.28) in those with aANXA5 levels ≥ 33.20 ng/mL.

CONCLUSION

AANXA5 is independently associated with an increased risk of PTB and PIH. The identified optimal predictive cutoff values are 32.77 ng/mL for PTB and 33.20 ng/mL for PIH.

Non-criteria and criteria antiphospholipid antibodies and their association with pregnancy outcomes in women with a history of miscarriage: A retrospective study

INTRODUCTION

The objective of this study was to investigate both antiphospholipid antibodies (aPLs) and non-criteria aPLs (NC-aPLs) in relation with pregnancy outcomes.

METHODS

We retrospectively analyzed 1574 pregnant women with experienced at least one miscarriage who were tested for aPLs and NC-aPLs, and compared their clinical characteristics, immune biomarkers, and pregnancy outcomes. The χ2 test or Fisher's exact test compared pregnancy outcomes among patients negative for all aPLs, positive for NC‑aPLs subtypes, and positive for criteria aPLs subtypes.

RESULTS

Multivariate logistic regression analysis indicated that positive aPLs (OR = 2.216, 95 % CI 1.381-3.558), and positive NC-aPLs (OR = 1.619, 95 % CI 1.245-2.106) are linked to adverse outcomes. For fetal loss, positive aPLs (OR = 2.354, 95 % CI 1.448-3.829), NC-aPLs (OR = 1.443, 95 % CI 1.076-1.936) were significant. Premature delivery was associated with positive NC-aPLs (OR = 2.102, 95 % CI 1.452-3.043). In the NC-aPLs positive group, the rate of adverse outcomes was higher in the multiple-positive subgroup (77.8 %) compared to the double-positive (52.3 %) and single-positive (37.0 %) subgroups. The rates of fetal loss and premature delivery were also higher in the multiple-positive NC-aPLs subgroup compared to the single-positive subgroup (48.1 % vs. 22.6 % for fetal loss and 57.1 % vs. 16.5 % for premature delivery).

DISCUSSION

Our findings suggest that both aPLs and NC-aPLs are associated with an increased incidence of adverse pregnancy outcomes, and patients presenting with multiple NC-aPLs positivity were found to have a higher incidence of adverse outcomes compared to their single-positive counterparts.

Preconception anti-annexin A5 antibodies are associated with subsequent live birth in women with recurrent miscarriage: A retrospective study from China

PROBLEM

To evaluate the correlation between the antiannexin A5 antibodies (aAnxA5) multiples of median (MOM) and subsequent pregnancy outcomes in women with recurrent miscarriage (RM).

METHODS

Totally, 310 RM women were included in this study and grouped into tertiles according to their MOM of preconception aAnxA5 circulating levels determined by ELISA. The effect of aAnxA5 on the pregnancy outcomes was performed using multiple logistic regression. The outcomes included early miscarriage (before 10 weeks of gestation), late miscarriage (between 10 and 24 weeks), ongoing pregnancy (beyond 10 weeks), and live birth (after 24 weeks) characterized by pregnancy with fetal heartbeat.

RESULTS

For each unit increase in aAnxA5 MOM, the odds of live birth after 24 weeks and ongoing pregnancy were reduced by 40.2% (OR = .598; 95%CI 0.406-0.882, P = .010) and 38.1% (OR = .619; 95%CI 0.424-0.904, P = .013), respectively, after adjusting for demographic and clinical characteristics. The rise in aAnxA5 MOM was associated with an increased risk of early miscarriage (OR = 1.616; 95%CI 1.106-2.361, P = .013) and miscarriage (early + late miscarriage) (OR = 1.671; 95%CI 1.134-2.464, P = .010). Further subgroup analyses showed a decreased risk of live birth rates after 24 weeks of gestation in the two subgroups: maternal age ≥35 years (OR = .131; 95%CI 0.026-0.652), and previous pregnancy loss ≥ 3 (OR = .381; 95%CI 0.173-0.837).

CONCLUSIONS

Higher preconception aAnxA5 MOM levels in women with RM may be linked with a decreased risk of live birth after 24 weeks and an increased risk of early miscarriage, especially in individuals aged ≥35 years or with previous pregnancy losses ≥3.

Preconception Non-criteria Antiphospholipid Antibodies and Risk of Subsequent Early Pregnancy Loss: a Retrospective Study

The aim of this study was to investigate the subsequent early pregnancy outcomes in women positive for non-criteria antiphospholipid antibodies (NC-aPLs) before pregnancy. A total of 273 patients who had experienced sporadic or recurrent pregnancy loss and had been screened for 13 NC-aPLs at preconception were recruited in this study from September 2019 to February 2022. Serum levels of NC-aPLs were measured by ELISA using specific kits. The primary outcome was early pregnancy loss, and the secondary outcomes were biochemical pregnancy, clinically confirmed pregnancy loss, and ongoing pregnancy. Among these subjects, 56 patients had one previous pregnancy loss, and 217 had recurrent pregnancy loss (RPL). The NC-aPLs (+) and NC-aPLs (-) groups had similar rates of early pregnancy loss (EPL) after adjustment, regardless of the number of positive NC-aPLs (aOR = 1.054, 95% CI 0.602-1.846). Other outcomes were comparable in both groups, including the rates of biochemical pregnancy (aOR = 1.344, 95% CI 0.427-4.236), clinically confirmed pregnancy loss (aOR = 0.744, 95% CI 0.236-2.344), and ongoing pregnancy (aOR = 0.949, 95% CI 0.542-1.660). Based on sensitivity analysis, the NC-aPLs (+) were not associated with adverse early pregnancy outcomes in women with RPL. Furthermore, the difference in gestational weeks of pregnancy loss between the two groups was also insignificant. This study found no evidence linking preconception NC-aPL positivity to early pregnancy outcomes but offers a reference for future research to clarify NC-aPLs' potential clinical impact.

Anti-prothrombin autoantibodies enriched after infection with SARS-CoV-2 and influenced by strength of antibody response against SARS-CoV-2 proteins

Antiphospholipid antibodies (aPL), assumed to cause antiphospholipid syndrome (APS), are notorious for their heterogeneity in targeting phospholipids and phospholipid-binding proteins. The persistent presence of Lupus anticoagulant and/or aPL against cardiolipin and/or β2-glycoprotein I have been shown to be independent risk factors for vascular thrombosis and pregnancy morbidity in APS. aPL production is thought to be triggered by-among other factors-viral infections, though infection-associated aPL have mostly been considered non-pathogenic. Recently, the potential pathogenicity of infection-associated aPL has gained momentum since an increasing number of patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been described with coagulation abnormalities and hyperinflammation, together with the presence of aPL. Here, we present data from a multicentric, mixed-severity study including three cohorts of individuals who contracted SARS-CoV-2 as well as non-infected blood donors. We simultaneously measured 10 different criteria and non-criteria aPL (IgM and IgG) by using a line immunoassay. Further, IgG antibody response against three SARS-CoV-2 proteins was investigated using tripartite automated blood immunoassay technology. Our analyses revealed that selected non-criteria aPL were enriched concomitant to or after an infection with SARS-CoV-2. Linear mixed-effects models suggest an association of aPL with prothrombin (PT). The strength of the antibody response against SARS-CoV-2 was further influenced by SARS-CoV-2 disease severity and sex of the individuals. In conclusion, our study is the first to report an association between disease severity, anti-SARS-CoV-2 immunoreactivity, and aPL against PT in patients with SARS-CoV-2.

Evaluation of the Diagnostic Value of Non-criteria Antibodies for Antiphospholipid Syndrome Patients in a Chinese Cohort

Objective

Although specific anti-phospholipid antibodies (aPLs) have been used in the diagnosis of the antiphospholipid syndrome (APS) for years, new biomarkers are required to increase its diagnostic and risk-predictive power. This study aimed to explore the value of several non-criteria aPLs in a Chinese cohort.

Methods

A total of 312 subjects, namely, 100 patients diagnosed with primary APS, 51 with APS secondary to SLE, 71 with SLE, and 90 healthy controls, were recruited. Serum anticardiolipin (aCL) IgG/IgM/IgA, anti-β2-glycoprotein I (aβ2GPI) IgG/IgM/IgA, anti-phosphatidylserine/prothrombin antibodies (aPS/PT) IgG/IgM, and anti-annexin A5 antibodies (aAnxV) IgG/IgM were tested using ELISA kits.

Results

Of the total number of patients, 30.46% and 6.62% with APS were positive for aCL or aβ2GPI IgA, respectively, while 39.07% and 24.50% were positive for aAnxV or aPS/PT for at least one antibody (IgG or IgM). The addition test of aCL IgA and aAnxV IgM assists in identifying seronegative APS patients, and IgG aPS/PT was linked to stroke.

Conclusion

Detection of aCL IgA, aβ2GPI IgA, aAnxV IgG/M, and aPS/PT IgG/M as a biomarker provides additive value in APS diagnosis and would help in risk prediction for APS patients in medical practice.

Antiphospholipid syndrome: the need for new international classification criteria

Introduction: As soon as the association of lupus anticoagulant (LAC) and anticardiolipin antibodies (aCL) with thrombosis and miscarriages was described in the 1980s, the definition of the antiphospholipid syndrome (APS) became a need. Early descriptions of the disease by members of the Graham Hughes team included broad categories and unexplained laboratory inclusions. Over time, new clinical and experimental data refined the criteria, especially the obstetric manifestations, as well as the laboratory criteria.Areas covered: The authors performed a review of the literature using the PubMed database, and the following keywords were used: 'antiphospholipid antibody', 'antiphospholipid syndrome', and 'criteria of antiphospholipid'. The history of antiphospholipid criteria, clinical and experimental advancements, and other expert opinions were included in this paper.Expert opinion: It has been 14 years since an international congress on antiphospholipid antibodies has generated new classification based on the recent extensive research performed in the field. Currently, there is a need to update the international APS classification taking into consideration the inclusion of new clinical criteria such as aPL-related nephropathy as well as new standardized antibody specificities (e.g., anti-phosphatidylserine/prothrombin antibodies) with the adoption of a standardized scoring system that can stratify APS patients.

Low prevalence of antiannexin A5 antibodies in unprovoked venous thrombosis

INTRODUCTION

The antiphospholipid syndrome (APS) is characterized by thrombosis or pregnancy morbidity, and the detection in the blood of at least one of three antiphospholipid antibodies (lupus anticoagulant, or anticardiolipin or anti-β₂ -glycoprotein I antibodies). Diagnosing APS is important so that secondary prophylaxis may be administered to reduce risk of recurrent thrombosis and/or pregnancy morbidity. In addition to APS-defining antibodies, there may be additional autoantibodies that have a role in thrombosis and/or pregnancy morbidity. Furthermore, some patients have clinical manifestations highly suggestive of APS but are persistently negative for the APS-defining antibodies ("seronegative APS") and instead, have other autoantibodies. Antiannexin A5 (aANXA5) autoantibodies have been associated with increased risk of thrombosis and pregnancy morbidity; levels are also reportedly higher in patients with venous thrombosis compared with healthy controls. The prevalence of aANXA5 among patients with unprovoked venous thrombosis is not well-documented and determination of the frequency of aANXA5 is the objective of this study.

METHODS

We analysed sera from 148 patients with unprovoked venous thrombosis who had undergone routine laboratory testing for the present APS-defining antibodies.

RESULTS

aANXA5 IgG and IgM were present in 6% and 1%, respectively.

CONCLUSION

Prevalence of these antibodies in unprovoked venous thrombosis is comparable with frequencies reported in healthy individuals and is far lower than the prevalence in women with pregnancy morbidity. This may indicate lack of association with venous thrombosis, however, adequately powered case-control studies will be required to resolve this and prevalence data from this study will assist in the design of such studies.

Anti-phospholipid antibodies and reproductive failures

Anti-phospholipid syndrome (APS) recapitulates the link between autoimmunity and pregnancy failure: Acquired anti-phospholipid antibodies (aPL) play a pathogenic role in pregnancy complications. The diagnosis of obstetric APS can easily be pursued when women present with laboratory and clinical features fulfilling the international classification criteria. Standard therapeutic approach to obstetric APS consists in the association of anti-platelet agents and anticoagulants. Most patients achieve a live birth thanks to conventional treatment; however, approximately 20% fail to respond and are managed with additional therapeutic tools added on the top of conventional treatment. Surely, a refinement of risk stratification tools would allow early identification of high-risk pregnancies that warrant tailored treatment. In real life, obstetricians and rheumatologists face complex diagnostic scenarios including women with pregnancy morbidities other than those mentioned in classification criteria such as one or two early losses and premature birth after 34 weeks due to preeclampsia or placental insufficiency, women with low-titer aPL not fulfilling criteria laboratory requirements, women with positive non-criteria aPL, asymptomatic aPL carriers, and infertile women found to be aPL-positive. This review focuses on some of the several unanswered questions related to diagnostic, prognostic, and therapeutic aspects in obstetric APS.

Profiles of criteria and non-criteria anti-phospholipid autoantibodies are associated with clinical phenotypes of the antiphospholipid syndrome

Background

Specific anti-phospholipids antibodies (aPLs) are used as classification criteria of the antiphospholipid syndrome (APS). These aPLs, although essential for diagnosis, do not predict disease phenotypes, which may require specific therapies. Non-criteria aPLs are rarely evaluated and their role is yet to be defined. In the current study, we aimed to examine the association between criteria and non-criteria aPLs and APS phenotypes.

Methods

Serum samples from 188 subjects, 130 APS patients and 58 controls were analyzed for the presence of 20 aPLs (IgG and IgM isotypes to cardiolipin (CL), beta2-glycoprotein1 (β2GP1), phosphatidic acid (P-acid), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI), phosphatidylserine (PS), annexin-5 (AN) and prothrombin (PT) using a line immunoassay (GA Generic Assays, Germany). Sero-positivity to the different aPLs/aPLs profiles was correlated to APS phenotypes (i.e. arterial thrombosis, CNS manifestations, venous thrombosis, relapsing disease, obstetric morbidity).

Results

In this cohort, arterial thrombosis was associated with accumulative number of ≥ 7/20 aPLs evaluated (OR 4.1; CI 95% 1.9–96, p = 0.001) as well as the sole presence of aPT (IgG) (OR 2.3;CI 95% 1.1–5.1, p = 0.03). CNS manifestations were linked with a profile of 4 aPLs (IgG): aPT, aPG, aPI and aAN (OR 2.6;CI 95% 1.1–6.3, p = 0.03). Symptom-free period of ≥ 3 years was linked with lower number of aPLs and the presence of aPI (IgG) (OR 3.0;CI 95% 1.08–8.1, p < 0.05) or aAN (IgG) (OR 3.4;CI 95% 1.08–10.9, p < 0.05). APS related pregnancy morbidity correlated with a profile of 2 aPLs (IgG): aCL and aPS (OR 2.9; CI 95% 1.3–6.5, p < 0.05) or the sole presence of aAN (IgG) (OR 2.8; CI 95% 1.02–8, p = 0.05).

Conclusion

In this study, we observed an association between specific criteria/non-criteria aPLs or aPLs profiles and clinical phenotypes of APS. Our data suggest that examination of a wider variety of aPLs may allow better characterization of APS.

Characteristics of pregnancy complications and treatment in obstetric antiphospholipid syndrome in China

OBJECTIVES

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by obstetric complications and thrombotic events associated with antiphospholipid antibodies (aPL). We aimed to compare the clinical characteristics and treatment of primary APS (PAPS) and secondary APS (systemic lupus erythematosus-APS, SAPS) patients and investigate risk factors associated with obstetric complications in Shanghai, China.

METHODS

We retrospectively collected and analyzed the data of obstetric APS (OAPS) patients from 2000 to 2017 in the APS-Shanghai (APS-SH) database.

RESULTS

One hundred eighty OAPS patients with a total of 450 pregnancies were included in this study. Two hundred twenty-one (49.11%) pregnancies resulted in miscarriage, and 161 (35.77%) pregnancies resulted in intrauterine death. In our cohort, when women were treated, 57 out of 66 pregnancies resulted in live births (86%). Of the 9 treated patients who failed to have live births, 3 had intrauterine deaths, 3 had fetal growth restriction, 2 had pneumorrhagia of the newborn, and 1 had a miscarriage. OAPS patients were divided into two groups: PAPS and SAPS. More SAPS patients than PAPS patients used glucocorticoids (GCs) and hydroxychloroquine (both p < 0.001). However, there was no significant difference in the GC dosage between SAPS and PAPS patients (p = 0.188). Lupus anticoagulant (LAC) and IgG aβ2GPI were risk factors for miscarriage (odds ratio (OR) = 2.398, 95% confidence interval (CI) = 1.276-4.505, p = 0.002; OR = 2.907, 95% CI = 1.558-5.405, p = 0.001, respectively) and intrauterine death (OR = 2.439, 95% CI = 1.299-4.580, p = 0.006; OR = 2.060, 95% CI = 1.089-3.897, p = 0.026, respectively).

CONCLUSIONS

The live birth rate of OAPS patients in Shanghai was 86%. Even if OAPS patients were treated, pregnancy complications could occur, and these patients might need further second-line treatment. Key Points • This is the first study to report data on Chinese OAPS patients. The live birth rate was 86%. • Lupus anticoagulant and IgG aβ2GPI were risk factors for miscarriage and intrauterine death in our cohort. • Despite active treatment, 9 patients had obstetric complications. Therefore, further second-line treatment is still needed.

Stroke and antiphospholipid syndrome-antiphospholipid antibodies are a risk factor for an ischemic cerebrovascular event

Testing for antiphospholipid antibodies could be an important part in determining the cause of a cerebrovascular event (CVE). Currently, it is also unknown whether antiphospholipid antibodies represent a risk factor for the development of a CVE and whether the selected therapy options are efficacious. So, this study aimed at (1) determining the frequency of patients experiencing a CVE and fulfilling the laboratory criterion for an antiphospholipid syndrome (APS), (2) investigating whether the persistent presence of antiphospholipid antibodies represented a risk factor for a CVE, and (3) focusing on the efficacy of the selected treatment strategy in the first year after the CVE. Eighty-nine patients with an acute CVE were prospectively followed for 1 year. At least two sera from each were tested for lupus anticoagulants, anticardiolipin, anti-β2-glycoprotein I, anti-phosphatidylserine/prothrombin and anti-annexin V antibodies. Twenty out of eighty-nine (22%) of CVE patients fulfilled the criteria for APS (17/20 for definitive and 3 for probable APS). There was a significant association between persistently present antiphospholipid antibodies and the CVE (OR, 4.62). No statistically significant difference was found in the CVE recurrence rate between APS-CVE and non-APS-CVE patients being treated mainly with acetyl salicylic acid. Antiphospholipid antibodies represent an independent risk factor for a CVE. In the first year after the CVE, antiplatelet therapy seemed to be sufficient in secondary CVE thromboprophylaxis in most APS patients.