A diverse array of genetic factors contribute to the pathogenesis of systemic lupus erythematosus

Lupus Nephritis: Current Perspectives and Moving Forward

Lupus nephritis is a severe organ manifestation of systemic lupus erythematosus, and its pathogenesis involves complex etiology and mechanisms. Despite significant knowledge gains and extensive efforts put into understanding the development and relapsing disease activity, lupus nephritis remains a substantial cause of morbidity and mortality in lupus patients. Current therapies retain a significant unmet medical need regarding rates of complete response, preventing relapse of lupus nephritis, progression of chronic kidney disease to kidney failure, drug toxicity, and pill burden-related drug non-adherence. Connected to progression of chronic kidney disease are the associated risks for disabling or even lethal cardiovascular events, as well as chronic kidney disease-related secondary immunodeficiency and serious infections. In this regard, biomarkers are needed that can predict treatment response to specific drugs to enable personalized precision medicine. A series of clinical trials with innovative immunomodulatory drugs are ongoing and raise expectations for improvements in the management of lupus nephritis. Here, we review how new developments in pathogenesis connect with current and future perspectives for the management of lupus nephritis.

Global and regional prevalence and incidence of systemic lupus erythematosus in low-and-middle income countries: a systematic review and meta-analysis

Systemic lupus erythematosus (SLE) may be more prevalent among most ethnic groups in the low-and-middle income countries (LMICs), still these countries are under-represented in epidemiological data on SLE. The aim of this study was to review the prevalence and incidence of SLE in LMICs and use meta-analytic techniques. The MEDLINE, CINHAL, Web of Science, Scopus and Global Index Medicus databases were searched for relevant studies published up to July of 2022. Papers selected for full-text review were included in the systematic review if they provided the prevalence or incidence of SLE in LMICs and published in English language. The reference lists of included articles were also searched for additional studies. Two individuals independently performed abstract and full-text review, data extraction, and quality assessment of the papers. The prevalence and incidence of SLE were pooled through random effects model. Pooled estimates were expressed with 95% confidence. Out of 2340 papers, 23 studies were included in the review. The mean age at diagnosis ranged from 25.5 to 45.8 years. Three studies were conducted in Argentina and Brazil, two studies in China and one study in Cuba, Colombia, Democratic Republic Congo, Ecuador, Egypt, India, Kenya, Malaysia, Mexico, Nigeria, Pakistan, Turkey, Ukraine, Venezuela, and Zimbabwe. The SLE prevalence and incidence varied from 3.2 to 159 per 100,000 and 0.3–8.7 per 100,000 persons, respectively. In a random effects meta-analysis (n = 10), the pooled prevalence of SLE was 103 (95% confidence interval [CI] – 17 to 224) per 100,000. Meta‐analysis of data from 6 incidence studies revealed an incidence of 5 cases per year (95% CI 2–8) per 100,000. According to WHO regions, the pooled prevalence of American and Western Pacific regions was 300 (95% CI – 200 to 900) and 36 (95% CI 35–37) per 100,000, respectively. The pooled incidence of the American region was 10 (95%, 0–14) per 100,000 inhabitants. Systemic lupus erythematosus is a common disease with considerable variation in prevalence and incidence among the general population in LMICs. Accurate estimates of prevalence and incidence of SLE are required to put in place appropriate programmes to reduce its burden in LMICs. PROSPERO registration number: CRD: 42020197495, https://www.crd.york.ac.uk/prospero/.

Genotype Triad for HOTAIR rs10783618, LINC-ROR rs1942347, and MALAT1 rs3200401 as Molecular Markers in Systemic Lupus Erythematous

Accumulating evidence supports the implication of long non-coding RNAs (lncRNAs) in autoimmune diseases, including systemic lupus erythematosus (SLE). LncRNA variants could impact the development and/or outcome of the disease with variable diagnostic/prognostic utility in the clinic. We aimed to explore the contribution of HOTAIR (rs10783618), LINC-ROR (rs1942347), and MALAT1 (rs3200401) variants to SLE susceptibility and/or severity in 163 SLE patients and age-/sex-matched controls using real-time TaqMan allelic discrimination PCR. HOTAIR rs10783618*C/C was associated with a 77% increased risk of SLE (OR = 1.77, 95%CI = 1.09−2.87, p = 0.020) under the recessive model. Similarly, MALAT1 rs3200401*T/T carriers were three times more likely to develop SLE (OR = 2.89, 95%CI = 1.42−5.90) under the recessive model. While the rs3200401*T/C genotype was associated with a 49−57% decreased risk of SLE under codominant (OR = 0.51, 95%CI = 0.31−0.82, p < 0.001) and over-dominant (OR = 0.43, 95%CI = 0.27−0.68, p < 0.001) models. LINC-ROR rs1942347*A/A patients were more likely to have a positive family history of SLE. At the same time, HOTAIR rs10783618*C/C was associated with a higher frequency of arthritis (p = 0.001) and the presence of oral ulcers (p = 0.002), while patients carrying rs10783618*T/T genotype were more likely to develop hair loss (p < 0.001), weight loss (p = 0.001), and neurological symptoms (p = 0.003). In conclusion, the studied lncRNAs, HOTAIR, and MALAT1 gene polymorphisms confer susceptibility for SLE, providing a potential theoretical basis for their clinical translation in SLE disease.

Association of microRNA-34a rs2666433 (A/G) Variant with Systemic Lupus Erythematosus in Female Patients: A Case-Control Study

Several microRNAs (miRNAs) are associated with autoimmune disease susceptibility and phenotype, including systemic lupus erythematosus (SLE). We aimed to explore for the first time the role of the miRNA-34a gene (MIR34A) rs2666433A > G variant in SLE risk and severity. A total of 163 adult patients with SLE and matched controls were recruited. Real-Time allelic discrimination PCR was applied for genotyping. Correlation with disease activity and clinic-laboratory data was done. The rs2666433 variant conferred protection against SLE development under heterozygous [A/G vs. G/G; OR = 0.57, 95%CI = 0.34-0.95], homozygous [A/A vs. G/G; OR = 0.52, 95%CI = 0.29-0.94], dominant [A/G + A/A vs. GG; OR = 0.55, 95%CI = 0.35-0.88], and log-additive [OR = 0.71, 95%CI = 0.53-0.95] models. Data stratification by sex revealed a significant association with SLE development in female participants under heterozygous/homozygous models (p-interaction = 0.004). There was no clear demarcation between SLE patients carrying different genotypes regarding the disease activity index or patients stratified according to lupus nephritis. Enrichment analysis confirmed the implication of MIR34A in the SLE pathway by targeting several genes related to SLE etiopathology. In conclusion, although the MIR34A rs2666433 variant conferred protection against developing SLE disease in the study population, it showed no association with disease activity. Replication studies in other populations are warranted.

Delayed Onset Minimal Change Disease as a Manifestation of Lupus Podocytopathy

Lupus podocytopathy (LP) is an uncommon manifestation of systemic lupus erythematosus (SLE) and is not included in the classification of lupus nephritis. The diagnosis of LP is confirmed by the presence of diffuse foot process effacement in the absence of capillary wall deposits with or without mesangial immune deposits in a patient with SLE. Here we describe a 13-year-old female who presented with nephrotic syndrome (NS) seven years after the diagnosis of SLE. The renal function had been stable for seven years since the SLE diagnosis, as manifested by the normal serum creatinine, serum albumin and absence of proteinuria. Renal biopsy showed evidence of minimal change disease without immune complex deposits or features of membranous nephropathy. Renal function was normal. The patient had an excellent response to steroid therapy with remission within two weeks. The patient remained in remission five months later during the most recent follow-up. This report highlights the importance of renal histology to determine the accurate etiology of NS in patients with SLE. Circulating factors, including cytokines such as interleukin 13, may play a role in the pathophysiology of LP and needs to be studied further in future larger studies.

Is podocytopathy another image of renal affection in p-SLE?

BACKGROUND

Lupus podocytopathy (LP) is a renal affection described in systemic lupus erythematosus (SLE) patients with nephrotic range proteinuria, characterized by diffuse foot process effacement without immune deposits and glomerular proliferation. This study describes LP, its pathological features and outcomes of pediatric (p-SLE) patients in comparison to the usual lupus nephritis (LN) cases.

METHODOLOGY

A retrospective cohort study conducted on a 10-year registration (2010-2019) of 140 p-SLE patients at the Pediatric Department, Tanta University. Histopathological analysis with light microscopy (LM) and immunofluorescence (IF) of all renal biopsies were evaluated according to the International Society of Nephrology Renal Pathology Society (ISN/RPS) grading system. In addition, some biopsies were examined with electron microscopy (EM).

RESULTS

Eighty-six p-SLE cases (61.4%) had renal involvement; seventy-nine biopsies (91.86%) of them met the classification criteria of LN as defined by ISN/RPS system. Five biopsies were normal (MCD) and two showed focal segmental sclerosis (FSGN) that did not meet any known classification of LN. Hence, they were reevaluated using EM that revealed diffuse effaced podocytes without glomerular sub-epithelial, endocapillary or basement membrane immune deposits, and were classified as having lupus podocytopathy, representing (8.14%) of all LN biopsies. Those seven cases showed good response to steroids with a complete remission duration of 3.40 ± 1.95 weeks. However, some case had 1-3 relapses during the duration of follow up.

CONCLUSIONS

LP is a spectrum of p-SLE, not an association as it is related to disease activity and its initial presentation.

Effects of Gasdermin D in Modulating Murine Lupus and its Associated Organ Damage

OBJECTIVE

Gasdermin D (GSDMD) is the key executioner of an inflammatory cell death mechanism known as pyroptosis. Recent reports have also implicated GSDMD in other mechanisms of cell death, including apoptosis, necroptosis, and NETosis. Given the role of dysregulated cell death in autoimmune syndromes such as systemic lupus erythematosus (SLE), this study was undertaken in a murine lupus model to investigate whether GSDMD plays a pathogenic role in systemic autoimmunity by promoting inflammatory cell death, leading to increased generation of nuclear autoantigens and autoantibodies.

METHODS

An imiquimod-induced model of SLE was tested in GSDMD^-/- mice (n = 30), with wild-type (WT) mice as controls (n = 34), on a C57BL/6 background. At the time of euthanasia, the mice were examined for serum autoantibodies, immune complex deposition, organ inflammation, immune dysregulation, and type I interferon responses. A model of pristane-induced lung injury in GSDMD^-/- mice (n = 7), with WT mice as controls (n = 10), was used to confirm the pulmonary phenotype. Regulation of various mechanisms of cell death by GSDMD was investigated in the mice.

RESULTS

Unexpectedly, GSDMD^-/- mice developed enhanced mortality, more severe renal and pulmonary inflammation, and exacerbated autoantibody production in response to imiquimod. Pulmonary involvement was also more severe in the absence of GSDMD in mice with pristane-induced lung injury. Compared to WT mice, lack of GSDMD was associated with increased levels of circulating nuclear autoantigens (P < 0.01), anti-double-stranded DNA autoantibodies (P < 0.01), tissue immune complex deposition (P < 0.05), expansion of myeloid cell subsets (P < 0.05), and enhanced B cell activation and plasma cell differentiation (P = 0.001). Moreover, in the absence of GSDMD, enhanced autoantigen generation was associated with increased local induction of cell death in vivo.

CONCLUSION

GSDMD negatively regulates autoantigen generation and immune dysregulation in response to tissue injury and may play previously unappreciated protective roles in systemic autoimmunity.

Infective dermatitis-like lesions as a novel skin manifestation of systemic lupus erythematosus

We describe a unique case of human T-lymphotropic virus 1 (HTLV-1)-associated infective dermatitis-like lesions in systemic lupus erythematosus. This suggests that some lupus patients may have immunological abnormalities resembling to those described in chronic HTLV-1 infection.

Suppression of autoreactive T and B lymphocytes by anti-annexin A1 antibody in a humanized NSG murine model of systemic lupus erythematosus

Systemic lupus erythematosus is a chronic inflammatory disease which involves multiple organs. Self-specific B and T cells play a main role in the pathogenesis of lupus and have been defined as a logical target for selective therapy. The protein annexin A1 (ANX A1) is a modulator of the immune system involving many cell types. An abnormal expression of ANX A1 was found on activated B and T cells during autoimmunity, suggesting its importance as a potential therapeutic target. We hypothesize that it may be possible to down-regulate the activity of autoreactive T and B cells from lupus patients in a humanized immunodeficient mouse model by treating them with an antibody against ANX A1. When cultured in the presence of anti-ANX A1, peripheral blood mononuclear cells (PBMC) from lupus patients showed a decreased number of immunoglobulin (Ig)G anti-dsDNA antibody-secreting plasma cells, decreased T cell proliferation and expression of activation markers and increased B and T cell apoptosis. We employed a humanized model of SLE by transferring PBMCs from lupus patients to immunodeficient non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice. The humanized animals presented autoantibodies, proteinuria and immunoglobulin deposition in the renal glomeruli. Treatment of these NOD-SCID mice with an anti-ANX A1 antibody prevented appearance of anti-DNA antibodies and proteinuria, while the phosphate-buffered saline (PBS)-injected animals had high levels after the transfer. The treatment reduced the levels of autoantibodies to several autoantigens, lupus-associated cytokines and disease symptoms.

Association of S100B polymorphisms and serum S100B with risk of systemic lupus erythematous in a Chinese population

The aim of this study was to investigate whether the S100B polymorphisms are associated with systemic lupus erythematous (SLE) in a Chinese population. A total of 313 SLE patients and 396 control subjects were enrolled in the present study. The genotypes of three SNPs (rs9722, rs881827 and rs1051169) in S100B gene were detected by single base extension polymerase chain reaction (SBE-PCR). Serum S100B levels were determined by enzyme-linked immunosorbent assay (ELISA). Rs1051169 was associated with an increased risk of SLE (C vs. G: adjusted OR=1.46, 95% CI, 1.18-1.80, p=0.001; CC vs. GG: adjusted OR=1.99, 95% CI, 1.32-3.02, p=0.001; CC+GC vs. GG: adjusted OR=1.54, 95% CI, 1.13-2.11, p=0.007; CC vs. GC+GG: adjusted OR=1.67, 95% CI, 1.16-2.42, p=0.006). Haplotype analysis showed that the G-G-C haplotype was associated with an increased risk of SLE (OR=1.50, 95% CI, 1.14-1.98, p=0.004). Stratified analyses showed that the rs1051169 polymorphism was associated with an increased risk of neurologic disorder in SLE patients (C vs. G: OR=1.78, 95% CI, 1.22-2.59, p=0.003; GC vs. GG: OR=2.33, 95% CI, 1.14-4.77, P=0.019; CC vs. GG: OR=3.02, 95% CI, 1.39-6.53, p=0.004; CC+GC vs. GG: OR=2.57, 95% CI=1.31-5.04, p=0.005). In addition, SLE patients with neurologic disorder carrying the rs1051169 GC/CC genotypes present a higher serum S100B levels compared with that carrying the GG genotype (p < 0.05). Our results indicate that the rs1051169 polymorphism may be involved in the pathogenesis of SLE.

Clinical characteristics of males with systemic lupus erythematosus (SLE) in an inception cohort of patients in Ghana

Background

Systemic Lupus Erythematosus (SLE) is said to be rare in Sub-Saharan Africa and even rarer in males worldwide. SLE is mostly considered a disease of women, though men may also be affected, and this may lead to a delay in diagnosis in men. The result is a greater burden of inflammation and subsequent organ damage over time.

Method

Data from the medical records of 13 male patients diagnosed with SLE at the Rheumatology Clinic of Korle- Bu Teaching Hospital between January 2014 and January 2017 was retrospectively analyzed.

Results

A total of 13 male patients out of a total of 134 SLE patients were included in our analysis. The mean age was 30.62 ± SD 8.47 years (range of 17 to 46 years). All of them (100%) presented with constitutional features. The most common ACR criteria observed was 61.5 % rash, 54.5 % oral ulcers, 92.3% arthritis, 61.5 % serositis and 38.5% renal involvement, 46.2 % CNS involvement. Looking at their serological profile, 91.7 % had a positive antinuclear antibody (ANA). 33.3 % had positive anti-dsDNA and 58.3 % extractable nuclear antigens. The mean duration from onset of symptoms to diagnosis was 21.31 months. Five patients were diagnosed with lupus nephritis, all at the time of diagnosis. There were no mortalities.

Conclusion

Male SLE patients in Ghana are comparable to other populations, with arthritis and constitutional features being predominant early features and lupus nephritis being the main early indicator of organ damage. This should warrant aggressive management in male patients.

Funding

None declared

Unique Characteristics of Prepubertal Onset Systemic Lupus Erythematosus

Objectives

The aim of this study was to investigate the influence of age at disease onset on disease expression and outcomes of pediatric systemic lupus erythematosus SLE (pSLE).

Methods

A total of 103 patients with pSLE from Sultan Qaboos University Hospital, Oman, were retrospectively studied. Epidemiological, clinical phenotype, disease severity, serology, treatment, and outcome were compared among the three groups using univariate statistical tests.

Results

The mean disease duration of the cohort was 9.8 ± 4.7 years. The patients were divided into three groups: prepubertal onset (n=39) with mean age at diagnosis of 5.1 ± 2.0 years and pubertal disease onset (n=29) with mean age at diagnosis of 10.8 ± 1.0 years as well as postpubertal disease onset (n=35) group with mean age at diagnosis of 15.3 ± 1.6 years. The prepubertal pSLE cohort demonstrates unique characteristics with increased frequency of familial SLE (61%) of which 49% were from first-degree relatives. Similarly, this group had distinctive clinical features, which included increased renal disease in pubertal and postpubertal groups, respectively (51% vs 23% vs 20%; p=0.039). Prepubertal, similar to pubertal group, had a higher incidence of cutaneous manifestations than in the postpubertal group (74% vs 69% vs 46%; p=0.029). Laboratory features in prepubertal group were distinct with increased frequency of positive anti-cardiolipin antibodies (47%), anti-glycoprotein antibodies (42%), ANCA (62%), and low complement levels (97%) compared to pubertal and postpubertal group. The prepubertal group also has the lowest frequency of positive SSA antibodies (18%) and SSB antibodies (5.1%). The overall mean SLEDAI score in pSLE cohort was 15.6 ± 18.5. The mean SLEDAI scores among the groups showed no significance difference (p=0.110). The overall SLICC DI ≥1 was 36% with a mean damage score of 0.76 ± 1.38. No significant differences in damage index (SLICC DI ≥1) were noted among the groups.

Conclusions

Distinct clinical features were identified in prepubertal onset pSLE population of Arab ethnicity. Given the high rate of consanguineous marriage and high frequency of familial SLE in this cohort, these manifestations could be explained by higher frequency of genetic factors that influence the disease pathogenesis.

Production of Therapeutic Enzymes by Lentivirus Transgenesis

Since ERT for several LSDs treatment has emerged at the beginning of the 1980s with Orphan Drug approval, patients' expectancy and life quality have been improved. Most LSDs treatment are based on the replaced of mutated or deficient protein with the natural or recombinant protein.One of the main ERT drawback is the high drug prices. Therefore, different strategies trying to optimize the global ERT biotherapeutic production have been proposed. LVs, a gene delivery tool, can be proposed as an alternative method to generate stable cell lines in manufacturing of recombinant proteins. Since LVs have been used in human gene therapy, clinical trials, safety testing assays and procedures have been developed. Moreover, one of the main advantages of LVs strategy to obtain manufacturing cell line is the short period required as well as the high protein levels achieved.In this chapter, we will focus on LVs as a recombinant protein production platform and we will present a case study that employs LVs to express in a manufacturing cell line, alpha-Galactosidase A (rhαGAL), which is used as ERT for Fabry disease treatment.

Effects of Major Epigenetic Factors on Systemic Lupus Erythematosus

The pathogenesis of systemic lupus erythematosus (SLE) is influenced by both genetic factors and epigenetic modifications; the latter is a result of exposure to various environmental factors. Epigenetic modifications affect gene expression and alter cellular functions without modifying the genomic sequences. CpG-DNA methylation, histone modifications, and miRNAs are the main epigenetic factors of gene regulation. In SLE, global and gene-specific DNA methylation changes have been demonstrated to occur in CD4+ T-cells. Moreover, histone acetylation and deacetylation inhibitors reverse the expression of multiple genes involved in SLE, indicating histone modification in SLE. Autoreactive T-cells and B-cells have been shown to alter the patterns of epigenetic changes in SLE patients. Understanding the molecular mechanisms involved in the pathogenesis of SLE is critical for the introduction of effective, target-directed and tolerated therapies. In this review, we summarize the recent findings that highlight the importance of epigenetic modifications and their mechanisms in SLE.

How compelling are the data for Epstein-Barr virus being a trigger for systemic lupus and other autoimmune diseases?

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) is caused by a combination of genetic and acquired immunodeficiencies and environmental factors including infections. An association with Epstein-Barr virus (EBV) has been established by numerous studies over the past decades. Here, we review recent experimental studies on EBV, and present our integrated theory of SLE development.

RECENT FINDINGS

SLE patients have dysfunctional control of EBV infection resulting in frequent reactivations and disease progression. These comprise impaired functions of EBV-specific T-cells with an inverse correlation to disease activity and elevated serum levels of antibodies against lytic cycle EBV antigens. The presence of EBV proteins in renal tissue from SLE patients with nephritis suggests direct involvement of EBV in SLE development. As expected for patients with immunodeficiencies, studies reveal that SLE patients show dysfunctional responses to other viruses as well. An association with EBV infection has also been demonstrated for other autoimmune diseases, including Sjögren's syndrome, rheumatoid arthritis, and multiple sclerosis.

SUMMARY

Collectively, the interplay between an impaired immune system and the cumulative effects of EBV and other viruses results in frequent reactivation of EBV and enhanced cell death, causing development of SLE and concomitant autoreactivities.

Associations of microRNA single nucleotide polymorphisms and disease risk and pathophysiology

Single nucleotide polymorphisms (SNPs) are genetic variations that contribute to human phenotypes associated with various diseases. SNPs are involved in the regulation of a broad range of physiological and pathological processes, such as cellular senescence, apoptosis, inflammation, and immune response, by upregulating the expression of classical inflammation markers. Recent studies have suggested that SNPs located in gene-encoding microRNAs (miRNAs) affect various aspects of diseases by regulating the expression or activity of miRNAs. In the last few years, miRNA polymorphisms that increase and/or reduce the risk of developing many diseases, such as cancers, autoimmune diseases, and cardiovascular diseases, have attracted increasing attention not only because of their involvement in the pathophysiology of diseases but also because they can be used as prognostic biomarkers for a variety of diseases. In this review, we summarize the relationships between miRNA SNPs and the pathophysiology and risk of diseases.

Genetic Variants in IL-12B and IL-27 in the Polish Patients with Systemic Lupus Erythematosus

To investigate the potential association between IL-12B and IL-27 gene polymorphisms and systemic lupus erythematosus (SLE), we performed a case-control study based on the Polish population. Patients with SLE and healthy individuals were examined for -6415 CTCTAA/GC (rs17860508) and +1188A/C (rs3212227) in IL-12B and -924A/G (rs153109) and 4730T/C (rs181206) in IL-27 gene polymorphisms using the high-resolution melting method, PCR-RFLP method and TaqMan SNP genotyping assay, respectively. An increased frequency of GC/GC genotype as well as GC allele of the IL-12B rs17860508 was found in patients with SLE, as compared with healthy subjects (P < 0.001). We did not find differences in genotype and allele frequencies of the IL-12B rs3212227 and IL-27 rs153109 and rs181206 variants between patients with SLE and controls. IL-27 haplotype rs181206C/rs153109G indicated higher risk for SLE (P = 0.002), whereas haplotype rs181206T/rs153109G indicated reduced risk for SLE (P = 0.005). The IL-12B rs3212227 A/C polymorphism was associated with the mean value of the platelets (PLT), urea and complement C3 level. Furthermore, IL-12B rs17860508 genetic variant showed correlation with PLT, prothrombin time, international normalized ratio and alkaline phosphatase. Our results revealed that IL-12B rs17860508 and IL-27 haplotype CG are genetic risk factors for SLE and that both IL-12B rs17860508 and rs3212227 predict disease phenotype.

Genetic Polymorphisms of rs3077 and rs9277535 in HLA-DP associated with Systemic lupus erythematosus in a Chinese population

Although the SLE risk gene loci of HLA-DR and HLA-DQ within the major histocompatibility complex (MHC) region has been gradually revealed by recent Genome-Wide Association studies (GWAS), the association of HLA-DP polymorphisms with SLE was minimally reported. Considering that the variants in rs3077 and rs9277535 in the HLA-DP region could influence the immune response by affecting antigen presentation of HLA class II molecules to CD4+ T cells, the present study aimed to explore the role of HLA-DP polymorphisms in SLE. In total, samples from 335 SLE patients and 635 healthy controls were collected and genotyped by a polymerase chain reaction-high resolution melting (PCR-HRM) assay. A significant positive correlation was observed between the SNP rs3077, rs9277535 of HLA-DP and SLE susceptibility (rs3077, OR = 0.74, 95%CI = 0.60-0.91, P = 0.004; rs9277535, OR = 0.72, 95%CI = 0.59-0.88, P = 0.001). Rs3077 polymorphism was corelated to IL-17, INF-γ and cutaneous vasculitis (P = 0.037, P = 0.020 and P = 0.006, respectively). Additionally, rs3077 AA genotype carriers showed lower concentration of inflammatory cytokines and lower cutaneous vasculitis incidence than did the other two genotype. No significant association was observed between rs9277535 and cytokines or any clinical features. In conclusion, HLA-DP polymorphisms (rs3077 and rs9277535) were associated with SLE susceptibility and the levels of some inflammatory cytokines in SLE patients.

APRIL gene polymorphism and serum sAPRIL levels in children with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multi-factor autoimmune disorder with diverse clinical manifestations and unclear pathogenesis. Genetic components play important roles in the incidence and development of SLE. Among these, APRIL as a cytokine has roles in the stimulation and antibody production in B cells. APRIL was hypothesized to be associated with SLE. The aim of this study was to assess the involvement of the APRIL gene in SLE susceptibility in Iranian patients. A single-nucleotide polymorphism (SNP) for rs11552708 of APRIL gene was analyzed by real-time PCR in 60 SLE Iranian children and 64 healthy controls. DNA samples of patients and healthy controls were extracted from peripheral blood leukocytes by phenol-chloroform. Serum samples obtained from 45 children with SLE and 45 healthy controls were assayed by enzyme-linked immunosorbent assay (ELISA). The G/G genotype (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.22-2.07; P = 0.68) and G allele (OR 0.81, 95% CI 0.25-2.56; P = 0.89) frequencies of polymorphism at codon 67 (67G) do not differ significantly in the SLE patients compared with those in the healthy controls. The serum APRIL levels in the SLE patients (mean ± SD = 29.27 ng/ml ± 20.77, range from 0 to 55.33 ng/ml) were significantly higher than those in the healthy controls (P = 0.02). Our results demonstrated that rs11552708 of the APRIL gene is not associated with SLE susceptibility in Iranian children. Likewise, these findings suggest that APRIL antagonist could be a potential therapeutic target to control SLE in children.

Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients

We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV) antigens in systemic lupus erythematosus (SLE) patients and healthy controls (HCs) to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired EBV-directed T-cell response. The concentrations of 14 cytokines (IL2, IL4, IL5, IL6, IL10, IL12, IL17, IL18, IL1β, IFNγ, TNFα, TNFβ, TGFβ, and GM-CSF) were quantified upon stimulation of whole blood with latent state antigen EBNA1, lytic cycle antigen EBV-EA/D, and the superantigen SEB. To avoid results affected by lack of lymphocytes, we focused on SLE patients with normal levels. Decreased induction of IL12, IFNγ, IL17, and IL6 upon EBNA1 stimulation and that of IFNγ, IL6, TNFβ, IL1β, and GM-CSF upon EBV-EA/D stimulation were detected in SLE patients compared to HCs. IFNγ responses, especially, were shown to be reduced. Induction of several cytokines was furthermore impaired in SLE patients upon SEB stimulation, but no difference was observed in basic levels. Results substantiate the previously proposed impaired regulation of the immune response against latent and lytic cycle EBV infection in SLE patients without lymphopenia. Furthermore, results indicate general dysfunction of leukocytes and their cytokine regulations in SLE patients.

HTLV-1, Immune Response and Autoimmunity

Human T-lymphotropic virus type-1 (HTLV-1) infection is associated with adult T-cell leukemia/lymphoma (ATL). Tropical spastic paraparesis/HTLV-1-associated myelopathy (PET/HAM) is involved in the development of autoimmune diseases including Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (SLE), and Sjögren's Syndrome (SS). The development of HTLV-1-driven autoimmunity is hypothesized to rely on molecular mimicry, because virus-like particles can trigger an inflammatory response. However, HTLV-1 modifies the behavior of CD4⁺ T cells on infection and alters their cytokine production. A previous study showed that in patients infected with HTLV-1, the activity of regulatory CD4⁺ T cells and their consequent expression of inflammatory and anti-inflammatory cytokines are altered. In this review, we discuss the mechanisms underlying changes in cytokine release leading to the loss of tolerance and development of autoimmunity.

Lupus nephritis is associated with poor pregnancy outcomes in pregnant SLE patients in Cape Town: a retrospective analysis

Introduction

Systemic lupus erythematosus (SLE) is a multi-system auto-immune disease common in females of child-bearing age. The effect of pregnancy on SLE and vice versa have not been well characterised in Africans. The aim of this study is to describe the pregnancy outcomes of patients with SLE presenting to the maternity department of Groote Schuur Hospital, Cape Town.

Methods

This study was designed as a retrospective review of records of pregnant women known with SLE and followed-up at the maternity section of Groote Schuur Hospital. The duration of survey was from the 1^st January 2003 to 31^st December 2013.

Results

There were 61 pregnancies reviewed in 49 patients; 80.3% of the pregnancies were in patients of mixed ancestry and the rest (19.7%) in black African patients. The mean age at presentation of the current pregnancy was 27.2±5.0 years. Mean gestational age at presentation and delivery was 13.0 ± 6.0 weeks and 28.9 ± 9.8 weeks respectively and 47.5% of the pregnancies were in patients with lupus nephritis (LN). Thirty nine (63.9%) pregnancies reached the third trimester and 11.5% of all pregnancies ended in the first trimester. There was a lower number of live births to mothers of African ancestry than to those of mixed ancestry (p=0.001). In 55.7% of the pregnancies, no flare was reported while a renal flare was reported in 23%. Pregnancies in patients with LN had higher frequencies of flares (58.6% vs 31.3%; p=0.032), pre-eclampsia (34.5% vs 12.5%; p=0.041), longer stay in hospital (12.0 ± 9.1 days vs 6.1 ± 5.1 days; p=0.004) and low birth weight babies (1.94 ± 1.02 kg vs 2.55±0.95 kg; p=0.046) than in patients without LN. Only 36 (59%) of the neonates were discharged home alive and of these 2 (5.6%) were to mothers of black African ancestry (p=0.001).

Conclusion

Increased lupus activity in pregnant SLE patients may account for the increased deaths of neonates born to SLE mothers. Patients of black African descent and those with LN tend to have a poorer outcome. A multi-disciplinary approach to the management of SLE patients (of child-bearing age or pregnant) needs to be further assessed for better outcomes.

The African Lupus Genetics Network (ALUGEN) registry: standardized, prospective follow-up studies in African patients with systemic lupus erythematosus

Background

The prevalence and severity of systemic lupus erythematosus (SLE) differs between ethnic groups and geographical regions. Although initially reported as rare, there is growing evidence that SLE is prevalent and runs a severe course in Africa. There is a paucity of prospective studies on African SLE patients.

Objective

The African Lupus Genetics Network (ALUGEN) is a multicentred framework seeking to prospectively assess outcomes in SLE patients in Africa. Outcomes measured will be death, hospital admission, disease activity flares, and SLE-related damage. We will explore predictors for these outcomes including clinical, serological, socio-demographic, therapeutic and genetic factors. Further, we will investigate comorbidities and health-related quality of life amongst these patients.

Methods

Data of patients recently (≤5 yrs) diagnosed with SLE will be collected at baseline and annual follow-up visits, and captured electronically. The ALUGEN project will facilitate standardized data capture for SLE cases in Africa, allowing participating centres to develop their own SLE registries, and enabling collaboration to enrich our understanding of inter-ethnic and regional variations in disease expression.

Conclusion

Comprehensive, high-quality multi-ethnic data on African SLE patients will expand knowledge of the disease and inform clinical practice, in addition to augmenting research capacity and networking links and providing a platform for future biomarker and interventional studies.

Clinical and immunological aspects and outcome of a Brazilian cohort of 414 patients with systemic lupus erythematosus (SLE): comparison between childhood-onset, adult-onset, and late-onset SLE

The clinical expression of systemic lupus erythematosus (SLE) is influenced by genetic and environmental factors and therefore varies between ethnicities. Information on the epidemiology of SLE in Brazil is scarce and practically limited to studies conducted in socioeconomically developed regions (South and Southeast). The objective of this study was to describe the clinical and immunological aspects and outcome of a cohort of patients with SLE treated at a university hospital in northeastern Brazil and compare patterns related to age at onset: childhood (cSLE), adult (aSLE), and late (lSLE). A random sample of 414 records (women: 93.5%) were reviewed. The mean age at SLE onset and the mean disease duration were 28.9 ± 10.9 years and 10.2 ± 6.6 years, respectively. Most patients had aSLE (n = 338; 81.6%), followed by cSLE (n = 60; 14.5%) and lSLE (n = 16; 3.9%). The female/male ratio was 6.5:1 in cSLE and 16.8:1 in aSLE; in lSLE, all patients were female (p = 0.05). During follow-up, the cSLE group presented higher rates of nephritis (70% vs. 52.9% vs. 12.5%; p = 0.0001) and leuko/lymphopenia (61.7% vs. 43.8% vs. 56.2%; p = 0.02). No significant differences were found for anti-dsDNA, anti-Sm, and antiphospholipid antibodies. Treatment with immunosuppressants was significantly more common, and higher doses of prednisone were used, in cSLE. The prevalence of cardiovascular diseases were more frequent in lSLE (p = 0.03). No significant differences were found between the three groups with regard to mean damage accrual (SDI), remission, and mortality. Although cSLE presented higher rates of nephritis and leuko/lymphopenia, more frequent use of immunosuppressants and higher prednisone doses than aSLE and lSLE, the three groups did not differ significantly with regard to damage accrual, remission, and mortality.

Unmet needs in autoimmunity and potential new tools

The term "autoimmunity" refers to a pathological condition in which the immunological tolerance of self-antigens is broken through, cross-reactive T cells are activated, and autoantibodies are produced by B cells. The intricate interplay among those aberrantly activated immune cells as well as inflammatory cytokines secreted by them contributes to the development of proinflammatory cascade which eventually leads to the occurrence of autoimmune diseases (AIDs) and organ damage. Autoimmune diseases occupy a broad spectrum of human diseases with more than 70 different disorders and afflict approximately 5-8 % of the world's population. AIDs can be categorized into organ-specific and systemic. Although the exact mechanism of AIDs remains elusive, it is generally believed that both genetic polymorphism and environmental exposure are involved in the development of AIDs. Aberrant epigenetic marks are also identified in patients with AIDs. In addition, dysregulation of innate immune system and molecular mimicry are indicated to play important roles in the initiation and maintenance of autoreactive inflammation. Based on the progress made in elucidating molecular mechanisms underlying AIDs, novel biomarkers for prediction, early diagnosis, prognosis and treatment response, and therapeutic strategies are proposed, which represents a promising future in the battle against AIDs. However, challenges remain regarding the clinical application of these potential new tools.

Central pathways causing fatigue in neuro-inflammatory and autoimmune illnesses

BACKGROUND

The genesis of severe fatigue and disability in people following acute pathogen invasion involves the activation of Toll-like receptors followed by the upregulation of proinflammatory cytokines and the activation of microglia and astrocytes. Many patients suffering from neuroinflammatory and autoimmune diseases, such as multiple sclerosis, Parkinson's disease and systemic lupus erythematosus, also commonly suffer from severe disabling fatigue. Such patients also present with chronic peripheral immune activation and systemic inflammation in the guise of elevated proinflammtory cytokines, oxidative stress and activated Toll-like receptors. This is also true of many patients presenting with severe, apparently idiopathic, fatigue accompanied by profound levels of physical and cognitive disability often afforded the non-specific diagnosis of chronic fatigue syndrome.

DISCUSSION

Multiple lines of evidence demonstrate a positive association between the degree of peripheral immune activation, inflammation and oxidative stress, gray matter atrophy, glucose hypometabolism and cerebral hypoperfusion in illness, such as multiple sclerosis, Parkinson's disease and chronic fatigue syndrome. Most, if not all, of these abnormalities can be explained by a reduction in the numbers and function of astrocytes secondary to peripheral immune activation and inflammation. This is also true of the widespread mitochondrial dysfunction seen in otherwise normal tissue in neuroinflammatory, neurodegenerative and autoimmune diseases and in many patients with disabling, apparently idiopathic, fatigue. Given the strong association between peripheral immune activation and neuroinflammation with the genesis of fatigue the latter group of patients should be examined using FLAIR magnetic resonance imaging (MRI) and tested for the presence of peripheral immune activation.

SUMMARY

It is concluded that peripheral inflammation and immune activation, together with the subsequent activation of glial cells and mitochondrial damage, likely account for the severe levels of intractable fatigue and disability seen in many patients with neuroimmune and autoimmune diseases.This would also appear to be the case for many patients afforded a diagnosis of Chronic Fatigue Syndrome.

The Neuro-Immune Pathophysiology of Central and Peripheral Fatigue in Systemic Immune-Inflammatory and Neuro-Immune Diseases

Many patients with systemic immune-inflammatory and neuro-inflammatory disorders, including depression, rheumatoid arthritis, systemic lupus erythematosus, Sjögren's disease, cancer, cardiovascular disorder, Parkinson's disease, multiple sclerosis, stroke, and chronic fatigue syndrome/myalgic encephalomyelitis, endure pathological levels of fatigue. The aim of this narrative review is to delineate the wide array of pathways that may underpin the incapacitating fatigue occurring in systemic and neuro-inflammatory disorders. A wide array of immune, inflammatory, oxidative and nitrosative stress (O&NS), bioenergetic, and neurophysiological abnormalities are involved in the etiopathology of these disease states and may underpin the incapacitating fatigue that accompanies these disorders. This range of abnormalities comprises: increased levels of pro-inflammatory cytokines, e.g., interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF) α and interferon (IFN) α; O&NS-induced muscle fatigue; activation of the Toll-Like Receptor Cycle through pathogen-associated (PAMPs) and damage-associated (DAMPs) molecular patterns, including heat shock proteins; altered glutaminergic and dopaminergic neurotransmission; mitochondrial dysfunctions; and O&NS-induced defects in the sodium-potassium pump. Fatigue is also associated with altered activities in specific brain regions and muscle pathology, such as reductions in maximum voluntary muscle force, downregulation of the mitochondrial biogenesis master gene peroxisome proliferator-activated receptor gamma coactivator 1-alpha, a shift to glycolysis and buildup of toxic metabolites within myocytes. As such, both mental and physical fatigue, which frequently accompany immune-inflammatory and neuro-inflammatory disorders, are the consequence of interactions between multiple systemic and central pathways.

Clinical perspectives on lupus genetics: advances and opportunities

In recent years, genome-wide association studies have led to an expansion in the identification of regions containing confirmed genetic risk variants within complex human diseases, such as systemic lupus erythematosus (SLE). Many of the strongest SLE genetic associations can be divided into groups based on their potential roles in different processes implicated in lupus pathogenesis, including ubiquitination, DNA degradation, innate immunity, cellular immunity, lymphocyte development, and antigen presentation. Recent advances have also shown several genetic associations with SLE subphenotypes and subcriteria. Many areas for further exploration remain to move lupus genetic studies toward clinically informative end points.

Association of miR-146a polymorphisms with systemic lupus erythematosus: a meta-analysis

Objective

miR-146a may play important roles in the pathogenesis of systemic lupus erythematosus (SLE). Several studies have examined the association of miR-146a gene polymorphisms with SLE, but these studies have shown inconclusive results. To verify whether an association exists, we conducted a meta-analysis of all relevant reports cited in MEDLINE/PubMed and EMBASE before August 2013.

Methods

Meta-analyses were performed on three published studies of the association between the miR-146a rs57095329 SNP and SLE for 5934 patients with SLE and 5591 controls as well as on four published studies of the association between miR-146a rs2910164 SNP and SLE for 2505 patients with SLE and 3248 controls. In addition, two studies involving 1920 SLE patients and 2472 controls were included in a meta-analysis of the association between miR-146a rs2431697 SNP and SLE. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were pooled by the inverse of their variance.

Results

Of three SNPs analyzed, rs57095329 (OR 1.25, 95%CI 1.17–1.35) and rs2431697 (OR 1.24, 95% CI 1.13–1.37) were genetically associated with SLE. However, no significant association was found between rs2910164 and SLE susceptibility (OR 0.98, 95% CI 0.90–1.06). There was no significant heterogeneity across studies and no evidence of publication bias.

Conclusions

The results of our meta-analysis suggest that miR-146a rs57095329 and rs2431697 SNPs are associated with SLE susceptibility. In addition, our results suggest that there is an ethnical difference between Asian and European populations in the association between miR-146a SNPs and SLE susceptibility.

Influence of sex differences on microRNA gene regulation in disease

Sexual dimorphism is observed in most human diseases. The difference in the physiology and genetics between sexes can contribute tremendously to the disease prevalence, severity, and outcome. Both hormonal and genetic differences between males and females can lead to differences in gene expression patterns that can influence disease risk and course. MicroRNAs have emerged as potential regulatory molecules in all organisms. They can have a broad effect on every aspect of physiology, including embryogenesis, metabolism, and growth and development. Numerous microRNAs have been identified and elucidated to play a key role in cardiovascular diseases, as well as in neurological and autoimmune disorders. This is especially important as microRNA-based tools can be exploited as beneficial therapies for disease treatment and prevention. Sex steroid hormones as well as X-linked genes can have a considerable influence on the regulation of microRNAs. However, there are very few studies highlighting the role of microRNAs in sex biased diseases. This review attempts to summarize differentially regulated microRNAs in males versus females in different diseases and calls for more attention in this underexplored area that should set the basis for more effective therapeutic strategies for sexually dimorphic diseases.

Lupus in Africa: can we dispel the myths and face the challenges?

The epidemiology of systemic lupus erythematosus (SLE) in Africa is largely undetermined, and the perception persists that the incidence of SLE on the continent is very low. Recent studies as well as our own experience, however, suggest that this is not the case. We have conducted a survey amongst medical practitioners in Africa to determine their experiences of diagnosing and treating SLE patients, and the results suggest that significant numbers of African patients are presenting with SLE. The apparent low incidence rate in Africa may be the result of underdiagnosis due to poor access to health care, low disease recognition within primary health care settings, limited access to diagnostic tools and inadequate numbers of specialist physicians. Treatment of SLE in Africa is also restricted by availability and affordability of immunosuppressive drugs. We have established the African Lupus Genetics Network (ALUGEN), an informal network of clinicians and researchers in Africa who have an interest in SLE, in order to facilitate combined clinical and research efforts towards improved outcomes for African SLE patients.

Update on differences between childhood-onset and adult-onset systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease and occurs worldwide in both children and adults. The estimated annual incidence among children is 2.22/100,000 and among adults is 23.2/100,000 in the United States. There is increasing understanding about differences in disease manifestations, medication use, and disease severity between those with childhood-onset SLE as compared with adult-onset SLE. Children have a more fulminant disease onset and course than adults with SLE, resulting in two to three times higher mortality. In future years, we anticipate more insight into the genetics between childhood-onset SLE and adult-onset SLE to help delineate the best therapies for both subsets of patients.

Perspectives of the relationship between IL-7 and autoimmune diseases

Interleukin (IL)-7 is one of the IL-2 family cytokines comprised of IL-2, IL-4, IL-7, IL-9, IL-15, as well as IL-21. IL-7 is mainly secreted by stroma cells in primary lymphoid tissues, playing an essential role in the program of T cell development. Recently, studies have revealed that physiological function exerted by immunocytes can be influenced by aberrant IL-7 signaling, which is common in abnormal autoimmunity regulation. There is also increasing evidence that IL-7 is involved in several autoimmune diseases, such as rheumatoid arthritis, type I diabetes, multiple sclerosis and systemic lupus erythematosus, etc. Targeting components in IL-7 signaling pathways may have potential significance for treating numerous autoimmune diseases. In this review, we therefore summarize our current understandings regarding the relationship between IL-7 and autoimmune diseases so as to render more valuable information on this kind of research.

Association of MeCP2 (rs2075596, rs2239464) genetic polymorphisms with systemic lupus erythematosus: a meta-analysis

Objective

Limited studies have shown an association between the methyl-CpG-binding protein2 ( MeCp2) genetic polymorphisms and systemic lupus erythematosus (SLE) in different populations, but the results are inconclusive. In order to get a precise and systematic estimation, a meta-analysis was performed.

Methods

A systematic literature search using English and Chinese databases (PubMed/Medline, Web of Knowledge, Wanfang Data (Chinese), etc.) for the eligible studies was performed. Based on heterogeneity among studies, random- or fixed-effects models were selected to analyze the risk of SLE associated with single-nucleotide polymorphisms (SNPs) of MeCP2 genetic polymorphisms.

Results

A significant increased risk of both SNPs of MeCP2 genetic variances associated with SLE was found. Analysis using a fixed-effects model found an increased risk of SLE with the A allele of rs2075596 (OR = 1.41, 95% CI: 1.34 to 1.49, p < 0.001), and the random-effects model also identified a risk factor of A allele of rs2239464 (OR = 1.31, 95% CI: 1.15 to 1.49, p = 0.001). Subgroup analysis and sensitivity analysis suggested that the major source of between-study heterogeneity stemmed from the difference between diverse ethnic groups. After omitting the smallest study, no publication bias was found, which further confirmed the reliability and stability of the meta-analysis.

Conclusions

Mutations of SNPs ( rs2075596, rs2239464) of MeCP2 showed increased risk of developing SLE. Large-scale multicenter epidemiological studies in selected populations with other risk factors are urgently required.