Immunological abnormalities in primary APS evolving into SLE: 6 years follow-up in women with repeated pregnancy loss

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.

Complementemia in pregnancies with antiphospholipid syndrome

Prognosis of pregnancies in women with antiphospholipid syndrome has dramatically improved over the past two decades using conventional treatment with low molecular weight heparin and low-dose aspirin. However, despite this regimen, 10-15% of antiphospholipid syndrome patients experience pregnancy losses. Several studies have been performed in order to identify risk factors predictive of complications. Thrombosis has been generally accepted as the key pathogenetic mechanism underlying pregnancy morbidity. However, the thrombogenic state alone is not able to explain all the different mechanisms leading to pregnancy failure. In fact, emerging evidence shows that complement pathway could play an important role in mediating clinical events in antiphospholipid syndrome. However, the exact mechanism through which complement mediates antiphospholipid syndrome complications remains unknown. Low complement levels (C3 and C4) are associated with poor pregnancy outcome in women with antiphospholipid syndrome in different studies. Hypocomplementemia could be indicated as an early predictor of adverse pregnancy outcome, available at the beginning of pregnancy for starting, if necessary, additional treatment to conventional therapy. However, future studies need to better understand the impact of low complement level on antiphospholipid syndrome pregnancy outcome.

Primary Antiphospholipid Syndrome Associated with Autoantibodies Against Golgi Bodies: A Case Report of a 32-Year-Old Female

Antiphospholipid syndrome is an autoantibody mediated disorder characterised by thrombotic manifestations and/or obstetric morbidity. The autoantibodies are directed against phospholipid binding plasma proteins. Amongst the clinical features abdominal presentation is an unusual feature in this syndrome. We present the case report of a 32-year female whose complaints was abdominal pain for one week and no history of previous foetal loss, who responded well to warfarin and has not developed systemic lupus erythematous even after follow up. Characteristic of this patient is the appearance of auto antibodies against Golgi bodies. Although antinuclear antibodies are seen in patients of rheumatic disease like systemic lupus erythematous, its presence in individuals with unusual presentation of antiphospholipid syndrome may facilitate in diagnosis.

Antiphospholipid syndrome: An update on risk factors for pregnancy outcome

BACKGROUND

The optimal treatment of women with primary antiphospholipid syndrome (APS) is still debated. About 20-30% of women with APS remain unable to give birth to healthy neonates despite conventional treatment, consisting of prophylactic-dose heparin and low-dose aspirin. These cases are defined "refractory obstetric APS". The early identification of risk factors associated with poor pregnancy outcome could be the optimal strategy to establish criteria for additional therapies, such as hydroxychloroquine, steroids, intravenous immunoglobulin, and plasma exchange.

PURPOSE

The aim of the present study was to review current literature about risk factors for poor pregnancy outcome.

SEARCH METHODS

The PubMed database was used to search for peer-reviewed original and review articles concerning risk factors for pregnancy outcome in APS from 1st January 1990 to 15th January 2018.

OUTCOMES

History of pregnancy morbidity and/or thrombosis, the association with SLE and/or other autoimmune diseases are well known history-based predictive factors for obstetrical complications, such as miscarriage, maternal venous thromboembolism, intrauterine foetal demise, preeclampsia, and neonatal death. Moreover, laboratory findings associated with poor pregnancy outcome are:triple antiphospholipid antibodies aPL positivity, double aPL positivity, single aPL positivity, false-positive IgM for CMV, and hypocomplementemia. Triple positivity is confirmed as the most significant risk factor by a large body of evidence. Furthermore, the abnormal uterine arteries Doppler velocimetry results are confirmed to be strongly associated with poor pregnancy outcomes in APS. The good performance of the uterine arteries velocimetry, as a negative predictive factor, was reported by different studies. On the contrary, in case of abnormal uterine arteries results, the relevance of a careful surveillance is highlighted for the high risk of maternal-foetal complications. Nevertheless, this tool is a late indicator to suggest any additional treatments.

CONCLUSIONS

In order to prevent obstetrical complications and establish the optimal combination therapy, the knowledge at preconception or at the beginning of pregnancy of risk factors associated with poor pregnancy outcome could be a crucial step for management and treatment of APS. In addition, in the preconception assessment a regimen with low-dose aspirin, folic acid, and vitamin D supplementation should be offered, and a treatment strategy has to be established (conventional vs additional therapy). In fact, additional treatment has to be tailored for each patient.

CD8+DR+ T-Cells and C3 Complement Serum Concentration as Potential Biomarkers in Thrombotic Antiphospholipid Syndrome

Purpose. To assess complement factors and T lymphocyte activation subset abnormalities in patients with thrombotic antiphospholipid syndrome (APS) as potential biomarkers for development of clinical complications. Methods. We assessed C3, C4, factor B concentrations (nephelometry), complement haemolytic functional activity (CH100, radial immune diffusion), and the activation status of CD4+ and CD8+ T-cells (three-colour flow cytometry) in patients with thrombotic APS. Antiphospholipid (aPL) positive patients without APS-related clinical criteria, systemic lupus erythematosus (SLE) patients, and healthy individuals were evaluated as controls. A clinical followup was performed to assess the potential relationship between the immunological parameters and development of APS-related complications. Results. Lower concentrations of C3 and higher levels of CD8+DR+ cells were risk factors for development of APS-related complications during followup, including rethrombosis and neuropsychiatric symptoms. Patients with diagnosed thrombotic APS had significantly lower levels of C3, C4, and CH100 as well as higher percentages of activated CD4+DR+ and of CD8+DR+ T-cells than healthy controls but similar to that observed in autoimmune disease controls. Conclusion. Lower C3 and C4 complement levels and higher percentages of CD8+DR+ T-cells were observed in thrombotic APS patients. The potential role of these abnormalities as biomarkers of clinical outcome warrants further evaluation in a multicenter study.

Distinct antibody profile: a clue to primary antiphospholipid syndrome evolving into systemic lupus erythematosus?

We have performed a retrospective study to determine if patients with antiphospholipid syndrome that developed systemic lupus erythematosus (APS/SLE) had distinct clinical and/or serological features. All 80 primary APS (PAPS) patients followed up at our APS unit were included in the study and divided into two groups: 14 APS/SLE and 66 PAPS. Prior or at onset of lupus manifestations, six patients were uniformly negative for lupus and Sjögren autoantibodies, and the other eight patients had persistent positive. In the first year after diagnosis of SLE, three patients remained with negative antibodies, the other seven patients maintained the same antibodies, and four patients developed other antibodies. APS/SLE group had a significant lower mean age at PAPS diagnosis (26.0 ± 8.0 vs. 34.2 ± 11.9 years, p = 0.03) and a longer disease duration (14.0 ± 7.0 vs. 6.0 ± 5.0 years, p < 0.0001). The mean time for PAPS to develop SLE was 5.2 ± 4.3 years. The typical clinical and laboratorial findings of APS did not discriminate both groups of patients. At lupus onset, antinuclear antibodies were more frequently observed in those who evolved to SLE (100 vs. 51.5%, p = 0.0005). Anti-double-stranded DNA (dsDNA), anti-ribosomal P, anti-Ro/SS-A, anti-La/SS-B, and anti-U1RNP antibodies were exclusively found in the APS/SLE patients, whereas anti-Smith (Sm) antibodies were not detected in both groups. The detection of a distinct subgroup of lupus-associated autoantibody in PAPS patients seems to be a hint to overt SLE disease, particularly in those patients with young age at diagnosis.

C6 knock-out mice are protected from thrombophilia mediated by antiphospholipid antibodies

BACKGROUND

Complement activation plays a role in pathogenesis of the antiphospholipid syndrome (APS), but the involvement of the C5b-9 membrane attack complex (MAC) is unknown. Here we studied the effects of human polyclonal antiphospholipid (aPL) antibodies on thrombosis and tissue factor (TF) up-regulation in C6 deficient (C6(-/-)) mice.

METHODS

C6(-/-) mice or the wild-type C3H/HeJ (C6(+/+)) mice were injected twice with IgG-APS (n = 2) or IgM-APS (n = 1) isolated from APS patients or with the corresponding control immunoglobulins (Igs) of normal human serum, (NHS) (IgG-NHS or IgM-NHS). Then, the sizes of induced thrombi in the femoral vein were determined 72 hours after the first injection. Tissue factor was determined in homogenates of carotid arteries and in peritoneal macrophages.

RESULTS

Thrombus sizes were significantly larger in C6(+/+) treated with IgG-APS1 or with IgG-APS2 or with IgM-APS when compared with C6(+/+) mice treated with IgG-NHS or with IgM-NHS, respectively. The sizes of thrombi were significantly smaller in the C6(-/-) mice injected with IgG-APS1, IgG-APS2 or IgM-APS (p < 0.001), compared to their C6(+/+) counterparts showing an important abrogation of thrombus formation in mice lacking C6. The TF expression and activity in the C6(-/-) mice treated with IgG-APS or IgM-APS were diminished when compared to C3H/HeJ (C6(+/+)) mice treated with the same Igs. All mice injected with IgG-APS and IgM-APS had medium-high titers of anticardiolipin (aCL) and anti-β(2)glycoprotein I (aβ(2)GPI) antibodies.

CONCLUSIONS

These data indicate that the C6 component of the complement system mediates aPL-thrombogenic effects, underscoring an important pathogenic mechanism and indicating the possibility of inhibiting complement to ameliorate APS-related manifestations.

Complement activation and pregnancy failure

Pregnancy represents a physiologic condition where maternal immune system tolerates the semi-allogenic fetus. The fetal tissues are directly exposed to the maternal blood with potential attacks from maternal immune system, including the activation of complement cascade. Small amounts, of both early and late components, of complement are physiologically found in the placenta, maybe in relation to the vascular remodeling process. A significant increase of complement activation was associated with different pathologic pregnancy outcomes, namely pre-eclampsia, recurrent spontaneous abortions, intra-uterine growth retardation, and anti-phospholipid syndrome (APS). In some, but not in all, mice models of APS, complement activation plays a major role in pregnancy loss, with a massive accumulation of C3 in the placenta, while C3 deficient mice didn't show fetal resorption. Basing on these findings, anti-phospholipid antibodies and complement activation (via C3a, C5a, and MAC) may cooperate in triggering a local inflammatory process, eventually leading to placental thrombosis, hypoxia, and neutrophil infiltration. However, histological analysis of human placenta tissues from APS women shows small rather than widespread inflammation. In a similar manner, complement activation can be detected in human APS placentas but without any relationship with pregnancy outcome and therapy. Further studies are necessary to investigate whether complement activation and inflammatory processes found in animal models are really taking place in APS.

Quantitative abnormalities of peripheral blood distinct T, B, and natural killer cell subsets and clinical findings in obstetric antiphospholipid syndrome

OBJECTIVE

Few studies have assessed immunophenotypic abnormalities on lymphocyte subsets in patients with antiphospholipid syndrome (APS). We performed an extended immunological study to define alterations of distinct T, B, and natural killer (NK) cell subsets in obstetric patients with APS and their relationship with APS-associated complications.

METHODS

PATIENTS AND CONTROLS

36 women with APS [Sydney criteria, Group A1 without thrombosis (n=26), Group A2 with thrombosis (n=10)]; and 36 age matched women with recurrent abortion without antiphospholipid antibodies (disease controls; Group B), 36 healthy parous women (healthy controls; Group C), and 36 healthy nonparous women (healthy controls; Group D). Thrombotic events occurred after history of abortions in all A2 women. Three-color whole-blood flow cytometry was used to characterize the distinct immunophenotypes.

RESULTS

A1 patients had significantly higher percentages of CD4+CD45RA-CCR7+ central memory cells (A1 vs D), higher percentages of activated CD4+CD25+ T cells (A1 vs D), and lower percentages and absolute counts of CD4+CD45RA-CCR7- effector memory cells (A1 vs D). Group A2 patients had higher percentages and absolute numbers of CD19+CD27-IgD+ naive B cells (A2 vs A1 vs all controls), lower percentages and absolute numbers of CD3-CD56+CD16+ NK cells (A2 vs all controls), and higher percentages of activated CD4+DR+ (A2 vs all controls), CD8+DR+ (A2 vs A1 vs C vs D), CD4+CD38+DR+ (A2 vs D), and CD4+CD25+DR+ T cells (A2 vs all controls). Increased percentages of CD8+DR+ T cells [relative risk (RR) 2.43, 95% CI 1.09-5.44, p=0.02] and of naive B cells (RR 3.05, 95% CI 1.30-7.11, p=0.009) were associated with development of thrombosis.

CONCLUSION

In obstetric patients with APS we documented significant changes in T, B, and NK cell homeostasis. Increased levels of CD8+DR+ and CD19+CD27-IgD+ cells might identify obstetric patients with APS at risk of having thrombosis.

Novel therapies for the antiphospholipid syndrome

Antiphospholipid antibodies (aPL Abs) are associated with thrombosis in patients with the antiphospholipid syndrome (APS). There is strong evidence that aPL Abs are pathogenic in vivo from studies in animal models. Furthermore, there are now convincing data indicating that activation of complement is involved in those processes. This report addresses current modalities of treatment, as well as recent findings with respect to molecular events triggered by aPL Abs on endothelial cells, platelets, monocytes and complement activation. A separate section addresses recent findings with regard to the putative receptor(s) recognized by aPL Abs on target cells. Based on experimental evidence using in vitro and in vivo models, new targeted therapies for treatment and/or prevention of thrombosis in APS are proposed and discussed.

Autoantibody explosion in antiphospholipid syndrome

Antiphospholipid syndrome (APS) is characterized by thrombosis and pregnancy loss in the presence of antiphospholipid antibodies (aPL), mainly anticardiolipin, anti-beta2-glycoprotein I and lupus anticoagulant. However, similar to systemic lupus erythematosus, APS is also characterized by multiple other autoantibodies including 'non-classical' aPL, as well as other antibodies. Herein we describe the autoantigen properties, prevalence and clinical importance of 30 different antibodies in APS. Among the other antibodies characterizing APS are autoantibodies directed to platelets, glycoproteins, various coagulation factors, lamins, mitochondrial antigens and cell surface markers. Few of these autoantibodies are correlated with the presence of other antibodies, and some may have an additive role in the pro-thrombotic tendency of the syndrome. This autoantibody explosion might be important in early identification of the syndrome and its manifestations.

New targeted therapies for treatment of thrombosis in antiphospholipid syndrome

Antiphospholipid (aPL) antibodies (Abs) are associated with thrombosis and pregnancy loss in antiphospholipid syndrome (APS), a disorder initially characterised in patients with systemic lupus erythematosus (SLE) but now known to occur in the absence of other autoimmune disease. There is strong evidence that aPL Abs are pathogenic in vivo, from studies of animal models of thrombosis, endothelial cell activation and pregnancy loss. In recent years, progress has been made in characterising the molecular basis of this pathogenicity, which includes direct effects on platelets, endothelial cells and monocytes as well as activation of complement. This review summarises the clinical manifestations of APS and current modalities of treatment, and explains recent advances in understanding the molecular events triggered by aPL Abs on target cells in coagulation pathways as well as effects of aPL Abs on complement activation. Based on this information and on additional scientific evidence using in vitro and in vivo models, new potential targeted therapies for treatment and/or prevention of thrombosis in APS are proposed and discussed.

Mechanisms of aPL-mediated thrombosis: effects of aPL on endothelium and platelets

Antiphospholipid antibodies (aPL) are associated with thrombosis and pregnancy loss in patients with systemic lupus erythematosus and antiphospholipid syndrome. Strong evidence demonstrates that aPL are pathogenic in vivo from studies that utilized animal models of thrombosis, endothelial cell activation, and pregnancy loss. However, the mechanisms by which aPL mediate disease are only partially understood, and our knowledge is limited by the polyspecificity of the antibodies, the multiple potential end-organ targets, and the variability of the clinical context in which the disease may present. This review discusses and summarizes the most current data available on molecular interactions and pathogenic mechanisms in antiphospholipid syndrome.

C5a Receptor-Deficient Mice Are Protected from Thrombophilia and Endothelial Cell Activation Induced by Some Antiphospholipid Antibodies

Recent findings indicate that complement activation--involving specifically C3 and C5--contributes to antiphospholipid (aPL)-mediated thrombosis. Two complement effector pathways are initiated by the cleavage of C5, C5a and C5b, which leads to the formation of the C5b-9 membrane attack complex. To delineate and distinguish the role of C5a from the C5b-9 membrane attack complex seeded by C5b, we examined the in vivo effects (thrombosis) of aPL on C5a receptor-deficient (C5aR-/-) mice. C5aR-/- and C5aR+/+ mice were injected with IgM or with IgG from two different patients with APS (IgM-APS or IgG-APS) or with control IgM or IgG (IgM-NHS or IgG-NHS) twice. Complement fixing activity of the Ig fractions and anticardiolipin activity in the sera of the mice were determined by enzyme-linked immunosorbent assay. Surgical procedures to study thrombus dynamics were performed. IgM-APS but not IgG-APS fixed C1q to cardiolipin-coated plates. IgM-APS significantly enhanced thrombus size in C5aR+/+ mice compared to C5aR+/+ mice treated with IgM-NHS (3198 +/- 2361 microm2 versus 585 +/- 460 microm2). C5aR-/- mice treated with IgM-APS showed a significant reduction in thrombi size as compared with C5aR+/+ mice (676 +/- 690 microm2 versus 3198 +/- 2361 microm2; P = 0.001). IgG-APS enhanced thrombus formation significantly in C5aR+/+ when compared to IgG-NHS-treated mice (3507 +/- 965 microm2 versus 1321 +/- 798 microm2), and these effects were not altered in C5aR-/- mice (3400 +/- 1681 microm2). The data indicate that C5aR-/- mice are protected from the thrombogenic effects of some aPL antibodies.

Complement activation in anti-phospholipid syndrome: A clue for an inflammatory process?

Anti-phospholipid syndrome (APS) is defined by recurrent arterial/venous thrombosis and/or fetal losses in the persistent presence of anti-phospholipid antibodies (aPL). In in vivo experimental models aPL thrombogenic activity is associated with a pro-inflammatory endothelial phenotype (increased adhesion molecule [ADM] expression and leukocyte adhesion) in addition to a pro-coagulant one (tissue factor [TF] expression). This is in line with the in vitro aPL ability to trigger intracellular signalling and to up-regulate ADM, TF and pro-inflammatory cytokine/chemokine expression at the mRNA and protein level in endothelial cells. Comparable effects were also reported in monocytes in vitro. In addition, complement activation is required by aPL to display their thrombogenic activity in in vivo models. Interestingly, complement activation blocking as well as Tumor Necrosis Factor alpha neutralization protect animals from aPL-induced fetal losses. Altogether these findings speak in favour for a role of inflammation in APS in spite of the absence of a clear inflammatory signature in the patients. We could not find any complement (C3c and C4d) deposition in the placentas from 2 late abortions (20 weeks of gestation) in APS women. Further studies are necessary to investigate whether complement activation and inflammatory processes found in animal models are taking place in APS patients.

Antiphospholipid antibodies and the antiphospholipid syndrome: an update on treatment and pathogenic mechanisms

PURPOSE OF REVIEW

The antiphospholipid syndrome is a disorder of recurrent thrombosis, pregnancy loss and thrombocytopenia associated with the presence of antiphospholipid antibodies and persistently positive anticardiolipin or lupus anticoagulant positive tests. Since its recognition in the 1980s, growing interest in the field, not only with respect to diagnosis and treatment, but also regarding the pathogenesis of antiphospholipid antibodies, has emerged.

RECENT FINDINGS

First, this review addresses the recently updated classification criteria for diagnosis and treatment of the antiphospholipid syndrome. A discussion on the newly described potential beneficial roles of hydroxychloroquine and the statins for the treatment of antiphospholipid syndrome-associated clinical manifestations is included. Importantly, this article analyzes recent data that examine the molecular and intracellular events that antiphospholipid antibodies trigger in target cells, as well as new findings in the identification of the receptors for these antibodies on the membrane of those cells. A separate section discusses novel pathogenic mechanisms of antiphospholipid antibodies, including the activation of complement and their interaction with homologous catalytic domains of several serine proteases of the coagulation system.

SUMMARY

Understanding the molecular interactions and the intracellular signaling that antiphospholipid antibodies trigger, new therapeutic and targeted strategies to ameliorate clinical manifestations in patients with antiphospholipid syndrome may be established.

Neuroendocrine Manifestations of Phospholipid Antibody Disease Identified by Long-Term Follow-Up Study of Patients with Phospholipid Antibodies

Recurrent clinical thrombotic episodes and/or recurrent fetal wastage are the clinical features of phospholipid antibody (aPL) syndrome, which is characterized by a bland thrombosis, but is not inflammatory, as is found in other connective tissue diseases such as systemic lupus erythematosus (SLE). Previous reports have suggested that some patients with primary aPL syndrome may progress to develop other autoimmune diseases, including inflammatory diseases such as SLE. The aim of this study was to determine the long-term outcome of women with aPL antibodies, with regard to progression of their underlying autoimmune disease. To that end, a retrospective study was made of women with aPL and primary aPL syndromes who had been followed at our institution for a minimum of 3 years. Charts were reviewed, patients interviewed, and laboratory tests were performed to determine whether the clinical nature of the disease and/or its autoantibody profile had changed. Thirty patients were enrolled into the study (29 with aPL syndrome, 1 with consistent aPL and no syndrome). Follow-up ranged from 3 to 22 years. Results were as follows: The autoimmune clinical features were unchanged in 27 patients, but 3 patients developed inflammatory disease, presenting with nasal chondritis (2), cutaneous vasculitis (3), and mucosal ulcer (1). In each case, these changes occurred during pregnancy or the immediate postpartum period. One patient fulfilled criteria for SLE as seen by a change in her autoantibody profile. Another incidental finding was that three other patients were diagnosed with papillary thyroid cancer, two being diagnosed during the follow-up period.

IN CONCLUSION

(1) Inflammatory disease may develop in some patients with aPL and appears to be set off by pregnancy, a known trigger for clinical thrombotic events in aPL patients. (2) Thyroid cancer may be associated with aPL, and this association warrants further study with larger number of patients.

Antiphospholipid syndrome in systemic lupus erythematosus: is the whole greater than the sum of its parts?

This article compares the manifestations of systemic lupus erythematosus (SLE) in the presence and absence of antiphospholipid antibodies (aPLs), the hallmark autoantibodies of antiphospholipid syndrome (APS). The combination of SLE and APS appears to be of greater concern than either entity alone. APS complicates SLE by adding a vaso-occlusive factor to the inflammatory component that adversely affects the prognosis of those who have lupus and aPLs. The increase in both morbidity and mortality when both are present has significant therapeutic implications. Anticoagulation may be a safer and more appropriate therapeutic option than instituting a regimen of corticosteroids and immunosuppressive agents with all their attendant adverse effects. It falls upon the physician to clearly define the disease entity and fully evaluate the disease process.

Long-term follow-up in 128 patients with primary antiphospholipid syndrome: do they develop lupus?

We retrospectively studied a large cohort of patients with primary antiphospholipid syndrome (APS) from 4 different referral centers to analyze the clinical and serologic features and, specifically, to determine the number of patients going on to develop systemic lupus erythematosus (SLE) or other autoimmune disease after long-term follow-up. The study included 128 unselected patients with primary APS who fulfilled the Sapporo International Criteria from 4 different tertiary hospitals in the United Kingdom, Mexico, and Spain. The patients had attended the referral centers between January 1987 and July 2001. We reviewed clinical and serologic characteristics according to a pre-established protocol. We used univariate analysis with the chi-squared or Fisher exact test and logistic regression to analyze possible factors related to the coexistence of SLE and APS. Ninety-seven female and 31 male patients fulfilled the criteria, with a median age of 42 +/- 12 years (range, 16-79 yr), and with a mean follow-up of 9 +/- 3 years (range, 2-15 yr). The main manifestations included deep vein thrombosis in 62 patients (48%), arterial thrombosis in 63 (49%) patients, pregnancy loss in 177/320 (55%) cases, and pulmonary embolism in 37 (30%) patients. Other clinical manifestations were migraine in 51 (40%) patients, thrombocytopenia in 48 (38%), livedo reticularis in 47 (37%), and valvular disease in 27 (21%). Serologic findings were anticardiolipin antibodies (aCL) IgG positive in 110 (86%) patients, aCL IgM in 36 (39%), lupus anticoagulant in 71 (65%), antinuclear antibodies in 47 (37%), and positive Coombs test in 5 (4%) patients. During the follow-up and after a median disease duration of 8.2 years (range, 1-14 yr), 11 (8%) patients developed SLE, 6 (5%) developed lupus-like disease, and 1 (1%) developed myasthenia gravis. The remaining 110 patients (86%) continued to have primary APS. After the univariate analysis, a family history of lupus, the presence of Raynaud phenomenon, migraine, psychiatric features, multiple sclerosis-like features, hemolytic anemia, low C3 and C4, and Coombs positivity conferred a statistically significant risk for the subsequent development of SLE (p < 0.05). Only the presence of Coombs positivity had statistical significance (odds ratio, 66.4; 95% confidence interval, 1.6-2714; p = 0.027) after the logistic regression evaluation. The current study confirms that progression from primary APS to SLE or lupus-like disease is unusual, even after a long follow-up. Only 3 patients developed anti-dsDNA antibodies. The presence of a positive Coombs test might be a marker for the development of SLE in patients with primary APS.

Defects in the disposal of dying cells lead to autoimmunity

The fast and efficient uptake of dying cells is of main importance to prevent contact of the immune system with intracellular autoantigens. Insufficient clearance of the latter is discussed to drive the humoral autoimmune response in systemic lupus erythematosus. Many adaptor molecules and receptors are involved in the recognition of dying cells. In this paper we focus on the involvement of phosphatidylserine, glycoproteins, and complement and DNaseI in the clearance of apoptotic and necrotic cells, respectively. Furthermore, extracellular danger signals released from necrotic cells are discussed and the uptake process of primary necrotic cells is investigated in detail. Last but not least, the character and origin of clearance defects observed in some systemic lupus erythematosus patients is presented.

Antibodies and clinical features of the antiphospholipid syndrome as criteria for systemic lupus erythematosus

The antiphospholipid syndrome (APS) can occur as a primary diagnosis or as a prominent feature of other diseases, predominantly systemic lupus erythematosus (SLE). The 1982 revised criteria for SLE were published prior to many of the studies which have illuminated current understanding of the antiphospholipid syndrome and several current clinical criteria for SLE, when arising from thrombotic damage to different organ systems, could be attributed to APS, leading to some confusion about where the diagnoses of these two disorders should begin and end. Additionally, APS is a significant generalized risk factor for irreversible organ damage and overall mortality in SLE patients and genetic linkages to HLA in APS hold up whether the disorder is primary or linked to SLE. It is increasingly recognized that APS itself is a complex, heterogenous disorder, involving a spectrum of autoantibodies to phospholipid-binding proteins, many of which have known coagulation-regulating functions. Although the combination of more than one antiphospholipid-related antibody might indicate a more severe phenotype, it is not suggested here that additive criteria for the diagnosis of SLE be accumulated with more than one of these pathologically related autoantibodies. Patients with multiple criteria for APS should be considered to have severe APS but it would be recommended to restrict APS-attributed criteria for SLE to a maximal of two: one immunologic and one clinical. Thus people meeting the Sapporo criteria for APS could gain only a maximum of two criteria for SLE, regardless of how many autoantibodies were detected or how severe the clinical syndrome might be. This would allow manifestations of fullblown APS an appropriate impact towards the diagnosis of SLE without leading to a premature diagnosis of SLE for people who might better be considered to have moderate to severe primary APS.

The prevalence, onset, and clinical significance of antiphospholipid antibodies prior to diagnosis of systemic lupus erythematosus

OBJECTIVE

To determine whether antiphospholipid antibodies (aPL) occur before the diagnosis of systemic lupus erythematosus (SLE) and before initial clotting events, and whether their presence early in the disease course influences clinical outcome.

METHODS

Serum samples obtained from 130 lupus patients before and after SLE diagnosis were screened for IgG and IgM aPL using an anticardiolipin (aCL) enzyme-linked immunosorbent assay. Medical records of all patients were carefully reviewed for data on the time of onset of SLE features meeting clinical criteria and on disease manifestations.

RESULTS

Twenty-four patients (18.5%) were positive for IgG and/or IgM aCL prior to SLE diagnosis. Anticardiolipin antibodies appeared from 7.6 years prior to SLE diagnosis to within the same month as SLE diagnosis, with a mean onset occurring 3.0 years before SLE diagnosis. Additionally, aCL presence early in the disease process seemed to predict a more severe clinical outcome; these patients eventually met an average of 6.1 of the 11 classification criteria for SLE, compared with 4.9 criteria for other patients (P < 0.001). The early aCL-positive population also had more frequent renal disease, central nervous system disease, thrombocytopenia, and clotting events. In this population, aCL preceded initial thrombotic events by a mean of 3.1 years.

CONCLUSION

Anticardiolipin antibodies in SLE patients tend to precede initial clotting events by several years. Furthermore, the presence of early, prediagnosis aPL seems to herald a more varied, severe clinical course with earlier onset in patients with SLE.

Exposure of anionic phospholipids serves as anti-inflammatory and immunosuppressive signal--implications for antiphospholipid syndrome and systemic lupus erythematosus

In contrast to necrotic cells, the clearance of apoptotic ones usually is an anti-inflammatory process which elicits only a marginal immune response. During apoptosis phosphatidylserine (PS) is exposed on the outer leaflet of the cytoplasmic membrane and serves as target for the PS receptor of phagocytes. The latter is responsible for anti-inflammatory signalling and the induction of TGFbeta. We were interested whether the immunogenicity of apoptotic cells can be increased by masking PS. We observed that treatment of xenogeneic apoptotic cells with annexin V (AxV) significantly increased the humoral immune response against surface epitopes of these cells. Furthermore, AxV-coated irradiated tumour cells were able to elicit a long lasting tumour specific cytotoxic T lymphocyte response. AxV efficiently blocked the uptake of irradiated cells by macrophages but not by dendritic cells. Furthermore, AxV skewed the phagocytosis of irradiated cells towards inflammation. Investigation of patients with autoimmune diseases further supported the role of anionic surface phospholipids for anti-inflammatory clearance of apoptotic cells. Impaired clearance and opsonisation with anti-phospholipid-antibodies are discussed to be responsible for the development of systemic lupus erythematosus and anti-phospholipid-syndrome, respectively. Presentation of cryptic epitopes from late apoptotic cells in a proinflammatory context may challenge T cell tolerance. In addition, accumulation of uncleared apoptotic debris in the germinal centres of lymph nodes may result in the survival of autoreactive B cells.

[Antiphospholipid antibodies evolving into connective tissue disease: follow-up study of women with recurrent misscarriage]

BACKGROUND AND OBJECTIVE

The aim of this study was to evaluate the clinical and immunologic profile, the rate of progression to connective tissue disease and the possible predictors of evolution in patients with antiphospholipid antibodies and abortions.

PATIENTS AND METHOD

In a prospective follow-up study, we determined the prevalence of antiphospholipid antibodies as well as other autoimmune abnormalities and the evolution to connective tissue disease in 200 women with unexplained recurrent abortions. IgG and IgM anticardiolipin antibodies were determined by ELISA and the lupus anticoagulant was determined by means of coagulometric tests.

RESULTS

Of 200 women with pregnancy losses, 69 (34.5%) had antiphospholipid antibodies. Thirty-one of 200 women (15.5%) had high or moderate positive anticardiolipin antibodies. During a mean follow-up of 32 months, 9 (13%) antiphospholipid-antibody-positive patients developed features of lupus- like disease or systemic lupus erythematosus. A low total hemolytic complement, increased circulating immune complexes and positive antinuclear antibodies (ANA) were more common in those patients evolving to a connective tissue disorder (p < 0.001, p = 0.003 and p < 0.001, respectively). Positive ANA in women with antiphospholipid antibodies predicted independently the evolution to a connective tissue disorder [Cox proportional hazard model; relative hazard = 4.92, p = 0.04].

CONCLUSIONS

A subgroup of patients with antiphospholipid antibodies and abortions may progress to a connective tissue disorder. A positive antinuclear antibody test result could be useful to identify those patients with antiphospholipid antibodies and abortions who are prone to evolve into a systemic autoimmune disease.