Vitamin D receptor (VDR) gene polymorphisms and susceptibility to systemic lupus erythematosus clinical manifestations

Exploring the contribution of genetics on the clinical manifestations of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by diverse clinical manifestations affecting multiple organs and systems. The understanding of genetic factors underlying the various manifestations of SLE has evolved considerably in recent years. This review provides an overview of the genetic implications in some of the most prevalent manifestations of SLE, including renal involvement, neuropsychiatric, cutaneous, constitutional, musculoskeletal, and cardiovascular manifestations. We discuss the current state of knowledge regarding the genetic basis of these manifestations, highlighting key genetic variants and pathways implicated in their pathogenesis. Additionally, we explore the clinical implications of genetic findings, including their potential role in risk stratification, prognosis, and personalized treatment approaches for patients with SLE. Through a comprehensive examination of the genetic landscape of SLE manifestations, this review aims to provide insights into the underlying mechanisms driving disease heterogeneity and inform future research directions in this field.

Vitamin D and Autoimmune Rheumatic Diseases

Vitamin D is a steroid hormone with potent immune-modulating properties. It has been shown to stimulate innate immunity and induce immune tolerance. Extensive research efforts have shown that vitamin D deficiency may be related to the development of autoimmune diseases. Vitamin D deficiency has been observed in patients with rheumatoid arthritis (RA) and has been shown to be inversely related to disease activity. Moreover, vitamin D deficiency may be implicated in the pathogenesis of the disease. Vitamin D deficiency has also been observed in patients with systemic lupus erythematosus (SLE). It has been found to be inversely related to disease activity and renal involvement. In addition, vitamin D receptor polymorphisms have been studied in SLE. Vitamin D levels have been studied in patients with Sjogren's syndrome, and vitamin D deficiency may be related to neuropathy and the development of lymphoma in the context of Sjogren's syndrome. Vitamin D deficiency has been observed in ankylosing spondylitis, psoriatic arthritis (PsA), and idiopathic inflammatory myopathies. Vitamin D deficiency has also been observed in systemic sclerosis. Vitamin D deficiency may be implicated in the pathogenesis of autoimmunity, and it may be administered to prevent autoimmune disease and reduce pain in the context of autoimmune rheumatic disorders.

Vitamin D receptor gene polymorphisms are associated with the risk and features of myasthenia gravis in the Han Chinese population

Vitamin D receptor gene (VDR) polymorphisms are candidate genetic variants for susceptibility to autoimmune diseases. Here, we explored the association between VDR polymorphisms and myasthenia gravis (MG) susceptibility and disease features in a Han Chinese population. A total of 151 patients with MG and 146 healthy controls were genotyped for VDR rs1544410, rs2228570, rs731236, and rs7975232 polymorphisms using the improved multiple ligase detection reaction. Information regarding age at onset, acetylcholine receptor (AChR-Ab) and muscle-specific kinase (MuSK-Ab) antibody status, thymus status, involved muscles at onset, and Osserman type at maximum worsening during 2-year follow-up was obtained and used for subclassification grouping. Intergroup comparisons of allele and genotype frequencies and haplotype distributions were performed between the MG and control groups and between each pair of MG subgroups. The VDR rs7975232 polymorphism was associated with the risk of MG in allele, codominant (CC vs. CA), and dominant models (p = 0.040, p = 0.018, and p = 0.018, respectively). Moreover, subjects with the ACC haplotype (order of rs731236, rs7975232, rs1544410) were more likely to develop MG than those with other haplotypes (OR = 1.486, 95% CI: 1.017-2.171, p = 0.040). In a dominant model, the rs7975232 CC genotype frequency was significantly higher in the ocular MG group than in the generalized MG group (p = 0.019). The study findings suggest that the VDR rs7975232 C allele and the ACC haplotype can be associated to an increased susceptibility to the development of MG. Trial registration: NCT05380128.

Modulation of Immune Cells as a Therapy for Cutaneous Lupus Erythematosus

Cutaneous lupus erythematosus (CLE) is an autoimmune disorder like systemic lupus erythematosus (SLE). Both SLE and CLE characterize autoantibody secretion and immune cell recruitment. In particular, CLE can be divided into three more frequent types, varying in the severity of the skin lesions they present. The role of type I IFN was shown to be one of the leading causes of the development of this pathology in the skin. Different treatments have been developed and tested against these different variants of CLE to decrease the increasing levels of CLE in humans. In this article, a literature revision discussing the similarities between SLE and CLE is carried out. In addition, new advances in understanding the development of CLE and the leading treatments being evaluated in animal models and clinical trials are reviewed.

Differential distribution of vitamin D receptor (VDR) gene variants and its expression in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disorder that displays an important genetic background. Vitamin D₃ (VD₃ ) through its receptor (VDR) plays an important immunomodulatory role in autoimmune misbalance, being capable of modulating immune responses. Genetic alterations in VDR gene may contribute to an altered risk in SLE development and clinical manifestations. We investigated VDR SNPs (single nucleotide polymorphisms) frequencies in 128 SLE patients and 138 healthy controls (HC) and mRNA differential expression in 29 patients and 17 HC regarding SLE susceptibility as well as clinical features. We observed that rs11168268 G allele (OR = 1.55, p = .01) and G/G genotype (OR = 2.69, p = .008) were associated with increased SLE susceptibility. The rs2248098 G allele and A/G and G/G genotypes were associated to lower SLE susceptibility (OR = 0.66, p = .01; OR = 0.46, p = .01; OR = 0.44, p = .02, respectively). Regarding clinical features, we observed lower risk for: rs11168268 A/G genotype and nephritis (OR = 0.31, p = .01); rs4760648 T/T genotype and photosensitivity (OR = 0.24, p = .02); rs1540339 T/T genotype and antibody anti-dsDNA (OR = 0.19, p = .015); rs3890733 T/T genotype and serositis (OR = 0.10, p = .01). We identified a significant downregulation in VDR expression levels when compared patients and controls overall (p = 1.04e^-7 ), in Cdx-2 A/G and G/G (p = .008 and p = .014, respectively) and in patients with nephritis (p = .016) Our results suggested that VDR SNPs influence upon SLE susceptibility and in particular clinical features, acting on mRNA expression in SLE patients overall and the ones with nephritis.

A complete physical mapping of the vitamin D receptor gene for dental implant loss: A pilot study

OBJECTIVES

The aim of this pilot case-control study was to investigate the association of clinical variables and genetic polymorphisms in the vitamin D receptor gene (VDR) with dental implant loss.

MATERIAL AND METHODS

This study was carried out with 244 individuals with mean age 51.90 ± 11.28 (81 cases and 163 controls matched by age, sex, and smoking habit). Also, the clusterization phenomenon was investigated stratifying the sample into two groups: (a) 34 patients with multiple losses (presenting two or more lost implants) and (b) 210 without multiple losses (up to one implant loss). Sociodemographic, clinical, and periodontal parameters were analyzed. The tagSNPs in the VDR gene were analyzed by real-time PCR. Univariate and multivariate analyses were performed (p < .05).

RESULTS

Edentulism, number of implants installed, and Gingival, Plaque, and Calculus Indexes were associated with implant loss in the univariate analysis. After the multivariate analysis, the allele G of rs3782905 in the recessive model, together with number of installed implants and Gingival Index, was associated with implant failure.

CONCLUSION

It is suggested that the allele G of rs3782905 in the recessive model may be a new genetic risk marker for dental implant loss in patients who lost two or more dental implants. In addition, number of implants installed and Gingival Index were also associated. Replication is mandatory to confirm these findings, due to the modest sample size of this work.

Cutaneous lupus erythematosus: new insights into pathogenesis and therapeutic strategies

Cutaneous lupus erythematosus (CLE) is an autoimmune disease that can present as an isolated skin disease or as a manifestation within the spectrum of systemic lupus erythematosus. The clinical spectrum of CLE is broad, ranging from isolated discoid plaques to widespread skin lesions. Histologically, skin lesions present as interface dermatitis (inflammation of the skin mediated by anti-epidermal responses), which is orchestrated by type I and type III interferon-regulated cytokines and chemokines. Both innate and adaptive immune pathways are strongly activated in the formation of skin lesions owing to continuous re-activation of innate pathways via pattern recognition receptors (PRRs). These insights into the molecular pathogenesis of skin lesions in CLE have improved our understanding of the mechanisms underlying established therapies and have triggered the development of targeted treatment strategies that focus on immune cells (for example, B cells, T cells or plasmacytoid dendritic cells), as well as immune response pathways (for example, PRR signalling, Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signalling and nuclear factor-κB signalling) and their cytokines and chemokines (for example, type I interferons, CXC-chemokine ligand 10 (CXCL10), IL-6 and IL-12).

Anti-carbamylated protein antibodies as a new biomarker of erosive joint damage in systemic lupus erythematosus

Background

The application of more sensitive imaging techniques, such as ultrasonography (US), changed the concept of non-erosive arthritis in systemic lupus erythematosus (SLE), underlining the need for biomarkers to identify patients developing the erosive phenotype. Anti-citrullinated peptide antibodies (ACPA), associated with erosions in inflammatory arthritis, have been identified in about 50% of patients with SLE with erosive arthritis. More recently, anti-carbamylated proteins antibodies (anti-CarP) have been associated with erosive damage in rheumatoid arthritis. We aimed to assess the association between anti-CarP and erosive damage in a large SLE cohort with joint involvement.

Methods

We evaluated 152 patients (male/female patients 11/141; median age 46 years, IQR 16; median disease duration 108 months, IQR 168). All patients underwent blood draw to detect rheumatoid factor (RF) and ACPA (commercial enzyme-linked immunosorbent assay (ELISA) kit), and anti-CarP (“home-made” ELISA, cutoff 340 aU/mL). The bone surfaces of the metacarpophalangeal and proximal interphalangeal joints were assessed by US: the presence of erosions was registered as a dichotomous value (0/1), obtaining a total score (0–20).

Results

The prevalence of anti-CarP was 28.3%, similar to RF (27.6%) and significantly higher than ACPA (11.2%, p = 0.003). Erosive arthritis was identified in 25.6% of patients: this phenotype was significantly associated with anti-CarP (p = 0.004). Significant correlation between anti-CarP titer and US erosive score was observed (r = 0.2, p = 0.01).

Conclusions

Significant association was identified between anti-CarP and erosive damage in SLE-related arthritis, in terms of frequency and severity, suggesting that these antibodies can represent a biomarker of severity in patients with SLE with joint involvement.

A population association study of vitamin D receptor gene polymorphisms and haplotypes with the risk of systemic lupus erythematosus in a Chinese population

The aim of the study is to investigate the association of vitamin D receptor (VDR) gene polymorphism, additional gene-gene interaction, and haplotype combination with systemic lupus erythematosus (SLE) risk. Pairwise linkage disequilibrium (LD) analysis was conducted using SNPstats. The association between four SNPs within VDR gene and SLE risk was investigated by logistic regression. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the interaction among four SNPs. Four SNPs within VDR gene were selected for genotyping in this study, including rs2228570, rs1544410, rs7975232, and rs731236. The T allele of rs2228570 and the G allele of the rs1544410 were associated with increased MM risk, adjusted ORs (95%CI) were 1.61(1.25-2.11) and 1.78 (1.34-2.23), respectively. GMDR analysis suggested a significant two-locus model (P = 0.0010) involving rs1544410 and rs2228570, and in this model, the cross-validation consistency was 10/10, and the testing accuracy was 62.70%. The haplotype analysis indicated that the most common haplotype was rs1544410-A and rs7975232-G haplotype, the frequencies of which were 0.4701 and 0.5467 in case and control group. Haplotype containing the rs1544410-G and rs7975232-T alleles were associated with increased SLE risk, OR (95%CI) = 2.08 (1.47-2.72), P < 0.001. We found that rs2228570 and rs1544410 within VDR gene, their interaction and haplotype containing the rs1544410-G and rs7975232-T alleles were all associated with increased SLE risk.

Vitamin D and juvenile systemic lupus erythematosus: Lights, shadows and still unresolved issues

Systemic lupus erythematosus (SLE) and juvenile SLE (jSLE) are autoimmune disorders naturally associated with several genetic, environmental, hormonal, and immunological contributing factors. It has been assumed that vitamin D deficiency may have a role in the immune activation of patients with SLE and play an active part in many comorbidities and even complications. A host of clinical studies suggested that vitamin D exerts inhibitory effects on many immunological abnormalities associated with SLE, also in children and adolescents, while different reports have hypothesized that vitamin D may be associated with accelerated cardiovascular disease in SLE. This review updates and summarizes the information related to the immunoregulatory effects of vitamin D and its importance in jSLE, discusses the innumerable correlations between vitamin D and disease activity, including clinical expression and gene polymorphisms of vitamin D receptor as well as the recommendations for vitamin D supplementation in these patients. Despite the excitement raised by many data obtained about vitamin D and its influence on several aspects of the disease, further well-designed perspective trials are required to define the exact role that vitamin D may have in the management of both SLE and jSLE.

Immunogenetics of cutaneous lupus erythematosus

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) is the prototypic autoimmune condition, often affecting multiple organ systems, including the skin. Cutaneous lupus erythematosus (CLE) is distinct from SLE and may be skin limited or associated with systemic disease. Histopathologically, the hallmark of lupus-specific manifestations of SLE and CLE is an interface dermatitis. The cause of SLE and CLE is likely multifactorial and may include shared genetic factors. In this review, we will discuss the genetic findings related to the cutaneous manifestations of SLE and isolated CLE, with a particular focus on the lupus-specific CLE subtypes.

RECENT FINDINGS

Several major histocompatibility complex and nonmajor histocompatibility complex genetic polymorphisms have been identified which may contribute to the cutaneous manifestations of SLE and to CLE. Most of these genetic variants are associated with mechanisms attributed to the pathogenesis of SLE, including pathways involved in interferon and vitamin D regulation and ultraviolet light exposure. Although there is overlap between the genetic factors associated with SLE and CLE, there appear to be unique genetic factors specific for CLE.

SUMMARY

Improved understanding of the genetics of CLE may lead to the creation of targeted therapies, improving outcomes for patients with this challenging dermatologic condition.

Therapeutic options for cutaneous lupus erythematosus: recent advances and future prospects

INTRODUCTION

Treatment and prevention are of critical importance in patients with cutaneous lupus erythematosus (CLE), as the disease can have a devastating effect on patient well-being and quality of life.

AREAS COVERED

We conducted a selective search of the PubMed database for articles published between December 2010 and November 2015. This review encompasses both non-pharmaceutical (photoprotection, smoking cessation, drug withdrawal, and vitamin D replacement) and pharmaceutical (topicals, antimalarials, immunosuppressives, biologics, etc.) interventions used in the treatment of CLE. Expert Commentary: Recent work has expanded our understanding of established therapies as well as introduced new treatments for consideration, though existing medications still prove inadequate for a subset of patients. Changes in trial design may help to alleviate this issue.

Eppur Si Muove: vitamin D is essential in preventing and modulating SLE

Systemic lupus erythematosus (abbreviated SLE or lupus) is a systemic autoimmune disease, with genetic, immunologic, hormonal, and environmental factors. 1 One of the environmental factors that has been studied over the years is vitamin D, which is created in the human body in response to exposure to sunlight and ultraviolet (UV) radiation.

This review aims at examining findings from recent years, specifically 2013–2014, regarding the relationship between vitamin D deficiency and SLE flares, severity, and clinical manifestation, as well as to examine the treatment options derived from this relationship.

Genetic Factors in Systemic Lupus Erythematosus: Contribution to Disease Phenotype

Genetic factors exert an important role in determining Systemic Lupus Erythematosus (SLE) susceptibility, interplaying with environmental factors. Several genetic studies in various SLE populations have identified numerous susceptibility loci. From a clinical point of view, SLE is characterized by a great heterogeneity in terms of clinical and laboratory manifestations. As widely demonstrated, specific laboratory features are associated with clinical disease subset, with different severity degree. Similarly, in the last years, an association between specific phenotypes and genetic variants has been identified, allowing the possibility to elucidate different mechanisms and pathways accountable for disease manifestations. However, except for Lupus Nephritis (LN), no studies have been designed to identify the genetic variants associated with the development of different phenotypes. In this review, we will report data currently known about this specific association.

Vitamin D receptor polymorphisms and expression profile in rheumatoid arthritis Brazilian patients

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation and important joint commitment, being the most common systemic autoimmune disease worldwide. RA displays important genetic background with a variety of genes contributing to the immune balance breakdown. Recent studies have demonstrated that vitamin D, through its receptor (VDR), is able to regulate the immune balance and suppress the autoimmunity process, being a potential target in autoimmune diseases. In the present genetic association study, we assessed 5 Tag single nucleotide polymorphisms (SNPs) (rs11168268, rs2248098, rs1540339, rs4760648 and rs3890733), which cover most of the VDR gene, in three different Brazilian populations (from Northeast, Southeast and South Brazil). We also evaluated the VDR expression profile in whole blood and monocytes from RA patients. For genotyping study, 428 RA patients and 616 healthy controls were genotyped with fluorogenic allele specific probes on an ABI7500 platform. For gene expression study, VDR mRNA levels of 15 RA patients and 26 healthy individuals were assessed by RT-PCR. Our results showed that SNPs rs4760648 and rs3890733 are associated to RA susceptibility (p value = 0.0026, OR 1.31 and p value = 0.0091, OR 1.28 with statistical power = 0.999 and 0.993, respectively). Regarding RA clinical features, the studied SNPs did not show significant associations. The gene expression assays showed that VDR mRNA levels were down regulated in both whole blood (-3.3 fold) and monocytes (-3.2 fold) of RA patients when compared to healthy controls. Our results, the first reported for distinct Brazilian populations, support a role of the VDR gene in the susceptibility to RA.

Immune Response Modulation by Vitamin D: Role in Systemic Lupus Erythematosus

Vitamin D plays key roles as a natural immune modulator and has been implicated in the pathophysiology of autoimmune diseases, including systemic lupus erythematosus (SLE). This review presents a summary and analysis of the recent literature regarding immunoregulatory effects of vitamin D as well as its importance in SLE development, clinical severity, and possible effects of supplementation in disease treatment.

Association between vitamin D receptor (VDR) gene polymorphisms and systemic lupus erythematosus in Portuguese patients

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin, in which both genetic and environmental factors are involved. One such environmental factor is vitamin D, a vital hormone that plays a specific function in the immune system homeostasis, acting through a nuclear receptor ( VDR) expressed in all immune cells. Several polymorphisms of the gene that encodes this receptor have been described. Though inconsistently, these polymorphisms have been associated with clinical manifestations and SLE development.

The aim of this study was to determine the possible association between VDR gene polymorphisms (BsmI, ApaI, TaqI e FokI) and SLE susceptibility and severity, in a cohort of lupus patients from the north of Portugal.

A total of 170 patients (F = 155, M = 15; age = 45 ± 13.4 years) with SLE (diagnosed according the American College of Rheumatology criteria) with at least five years of disease evolution and followed in the Autoimmune Disease Clinical Immunology Unit of Centro Hospitalar do Porto were studied. Patients and 192 ethnicity-matched controls were genotyped for BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236) and FokI (rs2228570) polymorphisms by TaqMan allelic discrimination assay. Disease severity was assessed by SLICC damage score, number of affected organs, number of severe flares and pharmacological history.

SLE patients with the CT genotype of FokI polymorphism have a higher SLICC value ( p = 0.031). The same result was observed for the group of patients with the TT genotype of TaqI polymorphism ( p = 0.046). No differences were observed in VDR genotype between patients and controls. Also, we observed that the other clinical features analysed were not influenced by VDR polymorphisms.

Our study confirms a possible role of VDR gene polymorphisms in SLE. A positive association was found between VDR polymorphisms and SLE severity (chronic damage). The presence of CT genotype of FokI and TT genotype of TaqI seems to confer a worse prognosis and may constitute a risk factor for higher long-term cumulative damage in SLE patients.

Systemic Lupus Erythematosus: Old and New Susceptibility Genes versus Clinical Manifestations

Systemic Lupus Erythematosus (SLE) is one of the most relevant world-wide autoimmune disorders. The formation of autoantibodies and the deposition of antibody-containing immune complexes in blood vessels throughout the body is the main pathogenic mechanism of SLE leading to heterogeneous clinical manifestations and target tissue damage. The complexity of etiology and pathogenesis in SLE, enclosing genetic and environmental factors, apparently is one of the greatest challenges for both researchers and clinicians. Strong indications for a genetic background in SLE come from studies in families as well as in monozygotic and dizygotic twins, discovering several SLE-associated loci and genes (e.g. IRF5, PTPN22, CTLA4, STAT4 and BANK1). As SLE has a complex genetic background, none of these genes is likely to be entirely responsible for triggering autoimmune response in SLE even if they disclosure a potentially novel molecular mechanisms in the pathogenesis' disease. The clinical manifestations and disease severity varies greatly among patients, thus several studies try to associate clinical heterogeneity and prognosis with specific genetic polymorphisms in SLE associated genes. The continue effort to describe new predisposing or modulating genes in SLE is justified by the limited knowledge about the pathogenesis, assorted clinical manifestation and the possible prevention strategies. In this review we describe newly discovered, as well as the most studied genes associated to SLE susceptibility, and relate them to clinical manifestations of the disease.