Synergistic enhancement of production of proinflammatory cytokines of human peripheral blood monocytes by anti-Sm and anti-RNP antibodies

Premature rupture of membranes - A cause of foetal complications among lupus: A cohort study, systematic review and meta-analysis

OBJECTIVE

The present study aimed to analyse the frequency of premature rupture of membranes (PROMs) among 190 women with systemic lupus erythematosus (SLE) followed up at the Hospital Universitário Pedro Ernesto from 2011 to 2018 and to review the literature on PROM in patients with SLE.

METHODS

A cohort study of SLE patients was conducted by analysing the following variables: sociodemographic characteristics, clinical manifestations of lupus, modified disease activity index for pregnancy, drugs used during pregnancy, intercurrent maternal infections and obstetric outcomes. Additionally, seven electronic databases (PubMed, Embase, Cochrane, Scielo, Scielo Brazil, Virtual Health Library Regional Portal and Google Scholar) were systematically searched. The search was updated on 3 February 2020.

RESULTS

Infections (relative risk (RR): 3.26, 95% confidence interval (CI): 1.5-6.7, p = .001), history of serositis (RR: 2.59, 95% CI: 1.31-5.11, p = .006) and anti-RNP positivity (RR: 3.08, 95% CI: 1.39-6.78, p = .005) were associated risk factors for PROM, while anti-RNP positivity (RR: 3.37, 95% CI: 1.35-8.40; p = .009) were associated with premature PROM (PPROM). The prevalence of PROM and PPROM was 28.7% and 12.9%, respectively. In the systematic review, the prevalence of PROM and PPROM was 2.7%-35% (I² = 87.62%) and 2.8%-20% (I² = 79.56%), respectively.

CONCLUSIONS

PROM, both at term and preterm, occurs more frequently in women with lupus than in the general population. A history of serositis, anti-RN, infections and immunosuppression during pregnancy may increase the susceptibility to PROM. The systematic review did not find any study with the main objective of evaluating PROM/PPROM in women with lupus.

What are the latest clinical findings regarding the association of neurotoxic brain antibodies found in the cerebrospinal fluid in patients with autoimmune disorders?

PURPOSE OF REVIEW

Recently, experiments show that the autoantibodies with direct access to neurons following blood brain barrier (BBB) disruption destroy neurons and lead to remodeling in damaged neurons. These are critical steps in autoantibody-mediated central nervous system disorder called neuropsychiatric syndromes in systemic lupus erythematosus (NPSLE). The purpose of this review is to examine therapeutic opportunities to repress neuronal remodeling by microglia after acute neuronal injury by autoantibodies.

RECENT FINDINGS

Recent studies have demonstrated that BBB disruption is a critical step for developing NPSLE, and serum anti-Sm antibodies have been significantly associated with BBB breakdown. In addition, it has been reported that antiglucose regulated protein-78 in patients with SLE also disrupt the BBB. Experiments with anti-N-methyl-D-aspartate antibodies show that HMGB1 and C1q were essential to activate microglia which, in turn, remodel damaged neurons in vivo. Interestingly treatment with angiotensin-converting enzyme inhibitor inactivated microglia and blunted neuronal remodeling as well as positively affected behavioral abnormalities.

SUMMARY

BBB disruption, acute neuronal damage and neuronal remodeling by activated microglia are all critical steps for NPSLE development, and each step will afford novel therapeutic targets.

Role of Serum IL-6 in Neuropsychiatric Systemic lupus Erythematosus

Objective

The present study was designed in order to elucidate the roles of serum interleukin 6 (IL‐6) in the pathogenesis in neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods

Paired serum and cerebrospinal fluid (CSF) samples were obtained from 101 patients with SLE when they presented active neuropsychiatric manifestations (69 patients with diffuse psychiatric/neuropsychological syndromes [diffuse NPSLE] and 32 patients with neurologic syndromes or peripheral nervous system involvement [focal NPSLE]) and from 22 control patients without SLE with noninflammatory neurological diseases. The levels of albumin and IL‐6 in CSF and sera were measured by enzyme‐linked immunosorbent assay.

Results

Serum IL‐6 and CSF IL‐6 were elevated in NPSLE compared with non‐SLE controls. Among NPSLE, serum IL‐6 and CSF IL‐6 were significantly elevated in acute confusional state (ACS) compared with non‐ACS diffuse NPSLE (anxiety disorder, cognitive dysfunction, mood disorder, and psychosis) or focal NPSLE. Q albumin (CSF/serum albumin quotient) was also significantly higher in ACS than in the other two groups of NPSLE. Of note, serum IL‐6 (r = 0.2801, p = 0.0207), but not CSF IL‐6 (r = 0.1602, p = 0.1918), was significantly correlated with Q albumin in patients with diffuse NPSLE, including ACS and non‐ACS.

Conclusion

These results indicate that serum IL‐6 as well as CSF IL‐6 is involved in the pathogenesis of NPSLE. Moreover, it is suggested that serum IL‐6 might play a most important role in blood‐brain barrier breakdown in NPSLE.

Developmental process in diffuse psychological/neuropsychiatric manifestations of neuropsychiatric systemic lupus erythematosus

Systemic lupus erythematosus (SLE) involves excessive autoimmune reactions, with pathogenesis characterized by autoantibody production. Although the specific mechanism underlying the development of neuropsychiatric syndromes in SLE (NPSLE) is still unclear, recent studies indicate the involvement of autoimmune pathophysiology. We previously identified the presence of anti-N-methyl-d-aspartate receptor subunit GluN2 antibody (anti-GluN2) as a functional autoantibody which is able to impair neurons and is essential for the diagnosis of diffuse psychiatric/neuropsychological syndromes in NPSLE (dNPSLE). Other autoantibodies like anti-Sm antibodies and anti-glucose-regulated protein 78 antibodies are known to compromise blood brain barrier (BBB) integrity. We demonstrated that high mobility group box-1 protein (HMGB1) decorates synapses on neurons damaged by anti-neuron antibodies, including anti-GluN2, where it behaves as a linker to enhance C1q binding to synapses in a dNPSLE model mouse. This C1q binding via HMGB1 is a critical step for remodeling by activated microglia, which leads to reductions in neuronal complexity and long-term behavioral abnormalities. Suppression of activated microglia can significantly reduce central nervous system (CNS) dysfunction. In this review, we describe the critical steps in the development of dNPSLE in particular, including the phases of BBB breakdown, acute neuronal damage by autoantibodies and neuronal remodeling due to activated microglia.

Diversity of neuropsychiatric manifestations in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterised by diverse organ damages resulting from various autoantibodies, such as antinuclear or anti-DNA antibodies. Neuropsychiatric lupus (NPSLE) refers to the neurological and psychiatric disorders complicated with SLE and can be challenging for physicians to manage. NPSLE has a broad spectrum and high heterogeneity of clinical phenotypes, including headaches, psychiatric symptoms and peripheral neuropathy. Additionally, various immune effectors have been reported to contribute to the pathogenesis, including cytokines, cell-mediated inflammation and brain-reactive autoantibodies. In some patients with SLE, neuropsychiatric symptoms develop for the first time after the initiation of the steroid treatment, hindering the differentiation from steroid psychosis. The administration of high doses of steroids in patients with SLE is believed to trigger psychiatric symptoms. No clear evidence has yet been found regarding the treatment of NPSLE. Therefore, NPSLE-specific markers need to be developed, and treatment guidelines should be established. This article provides an overview of NPSLE as well as its pathogenesis and treatment.