Detection of autoimmune antibodies in localized scleroderma by synthetic oligonucleotide antigens

Synthetic Nucleic Acid Antigens in Localized Scleroderma

We investigated the impact of synthetic nucleic acid antigens on the autoantibody profiles in patients with localized scleroderma, an autoimmune skin disease. Anti-DNA antibodies, including double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA), are common among autoimmune diseases, such as systemic lupus erythematosus and localized scleroderma. Based on recent studies, we hypothesized that the sequence of nucleic acid antigens has an impact on the autoimmune reactions in localized scleroderma. To test our hypothesis, we synthesized a panel of DNA and RNA antigens and used them for autoantibody profiling of 70 children with localized scleroderma compared with the healthy controls and patients with pediatric systemic lupus erythematosus (as a disease control). Among the tested antigens, dsD4, which contains the sequence of the human oncogene BRAF, showed a particularly strong presence in localized scleroderma but not systemic lupus erythematosus. Disease activity in patients was significantly associated with dsD4 autoantibody levels. We confirmed this result in vivo by using a bleomycin-induced mouse model of localized scleroderma. When administered intraperitoneally, dsD4 promoted an active polyclonal response in the mouse model. Our study highlights sequence specificity for nucleic acid antigens in localized scleroderma that could potentially lead to developing novel early-stage diagnostic tools.

The expanding role of synthetic nucleic acids for diagnosis and treatment

PURPOSE OF REVIEW

The presence of autoantibodies is a characteristic and diagnostic index of systemic lupus erythematosus (SLE). Antidouble-stranded DNA (antids-DNA) antibodies are the most frequent autoantibodies found in SLE related to the diagnosis and disease activity of SLE, and are measured by established methods like ELISA as a polyclonal autoantibody. However, there is no reliable data on the relationship between the respective reactivity of these polyclonal antids-DNA antibodies against different epitopes generated from the original antigen and the disease phenotype. Of the complications in SLE, neuropsychiatric SLE (NPSLE) is a troublesome and frequent phenotype of the disease but no specific diagnostic autoantibodies in serum have been found. First in this review, the possibility of antids-DNA antibodies for identifying primary NPSLE in patients with SLE based on the reactivity of different synthetic nucleic acids is described as a diagnostic marker. The purpose of this review is to examine diagnostic and therapeutic opportunities to modulate autoimmune in the central nervous system (CNS) developing the CNS inflammatory disorders.

RECENT FINDINGS

Khatri et al. investigated antids-DNA antibodies in order to develop a reliable method based on the application of synthetic nucleic acids and protein-based antigen arrays to characterize autoreactive antibodies specially for NPSLE. They found autoantibodies in three particular synthetic double stranded antigens and the antinuclear antibody patterns in ordinary lupus and NPSLE. These discoveries are leading to precision medicine in the CNS inflammatory disorders.

SUMMARY

Verifying the similarity of antids-DNA obtained from patients with NPSLE can be useful as a diagnostic marker. mRNA vaccination can locally suppress autoimmunity in the CNS associated with critical steps for the develop of CNS autoinflammation. Synthetic nuclei acids may provide a diagnostic and therapeutic target in patients with autoimmune CNS inflammatory disorders.

Upcoming treatments for morphea

Morphea (localized scleroderma) is a rare autoimmune connective tissue disease with variable clinical presentations, with an annual incidence of 0.4-2.7 cases per 100,000. Morphea occurs most frequently in children aged 2-14 years, and the disease exhibits a female predominance. Insights into morphea pathogenesis are often extrapolated from studies of systemic sclerosis due to their similar skin histopathologic features; however, clinically they are two distinct diseases as evidenced by different demographics, clinical features, disease course and prognosis. An interplay between genetic factors, epigenetic modifications, immune and vascular dysfunction, along with environmental hits are considered as the main contributors to morphea pathogenesis. In this review, we describe potential new therapies for morphea based on both preclinical evidence and ongoing clinical trials. We focus on different classes of therapeutics, including antifibrotic, anti-inflammatory, cellular and gene therapy, and antisenolytic approaches, and how these target different aspects of disease pathogenesis.

Localized scleroderma: actual insights and new biomarkers

Localized scleroderma (LS, morphea, limited scleroderma, focal scleroderma) is a chronic autoimmune disease characterized by a progressive damage to the connective tissue with a predominance of fibrosclerotic disorders in the skin and the subcutaneous tissue. In addition surrounding structures may be affected: fascia, muscle, and bone tissues. This review reflects the current understanding about limited scleroderma, its pathogenesis, diagnosis, new biomarkers, and information about the possibilities of its transition to systemic scleroderma. The following new biomarkers have been identified: galactosylated IgG (Ig-Gal), progranulin (PGRN), chemokine CCXL 18, various types of microRNA (miRNA-let-7a, miRNA-7, miRNA-196a, miRNA-155, miRNA-483-5p), periostin, and myelin basic protein (MBP). Knowledge about new biomarkers of LS will help us to explore the patients' predisposition to the development of systemic scleroderma. In addition, by acting on these biomarkers, it is possible to prevent the progression of LS in the early stages and its transition to systemic scleroderma. The review also presents the current understanding of autoantibodies in LS and their correlation with clinical signs of the disease.

Ultra-fast detection and quantification of nucleic acids by amplification-free fluorescence assay

Two types of clinically important nucleic acid biomarkers, microRNA (miRNA) and circulating tumor DNA (ctDNA) were detected and quantified from human serum using an amplification-free fluorescence hybridization assay. Specifically, miRNAs hsa-miR-223-3p and hsa-miR-486-5p with relevance for rheumatoid arthritis and cancer related mutations BRAF and KRAS of ctDNA were directly measured. The required oligonucleotide probes for the assay were rationally designed and synthesized through a novel "clickable" approach which is time and cost-effective. With no need for isolating nucleic acid components from serum, the fluoresence-based assay took only 1 hour. Detection and absolute quantification of targets was successfully achieved despite their notoriously low abundance, with a precision down to individual nucleotides. Obtained miRNA and ctDNA amounts showed overall a good correlation with current techniques. With appropriate probes, our novel assay and signal boosting approach could become a useful tool for point-of-care measuring other low abundance nucleic acid biomarkers.

Serological comparison of systemic lupus erythematosus with neuropsychiatric lupus using synthetic nucleic acid antigens

Neuropsychiatric systemic lupus erythematosus is an autoimmune disorder characterized by an irregular exchange between the central nervous system and the immune system, leading to the outbreak of neurological conditions with possible disabling effects. Although neuropsychiatric systemic lupus erythematosus is the most common expression of lupus condition, it is still poorly understood. In this study, we focus on the development of an advantageous method based on the application of synthetic nucleic acids and protein-based antigen arrays in order to characterize autoreactive antibodies in neuropsychiatric systemic lupus erythematosus. We confirmed the benefits of using synthetic oligonucleotides such as assay reproducibility, elevated affinity and specificity to autoreactive antibodies. We also demonstrated presence of autoantibodies towards three particular synthetic double stranded antigens and verify similarity of antinuclear antibody patterns in ordinary lupus and neuropsychiatric systemic lupus erythematosus.

Combined Assay for Detecting Autoantibodies to Nucleic Acids and Apolipoprotein H in Patients with Systemic Lupus Erythematosus

The complicated clinical picture and biomolecular pattern of human autoimmune diseases (ADs) make knowledge on their etiology still fragmentary. The diagnostic approaches for ADs require improvement both for clinical and research effort to progress. Synthetic biomolecular antigens find growing applications for diagnosis and investigation of ADs. The main goal of this work is to detect interaction between synthetic antigens and autoantibodies in systemic lupus erythematosus within a combined, high-throughput assay. A panel of synthetic antigens has been prepared from DNA, RNA, locked nucleic acids and apolipoprotein H. The binding of synthetic antigens to autoantibodies has been confirmed in sera samples from those with active systemic lupus erythematosus (SLE) by indirect enzyme linked immunosorbent assay. Our study provides an efficient methodology for combined autoantibody profiling in SLE.

Diagnosis and management of linear scleroderma in children

PURPOSE OF REVIEW

Linear scleroderma is the most common subtype of localized scleroderma (LoS) in children. It can be associated with extracutaneous manifestations and long-term sequelae. Thus, appropriate diagnosis and management are key to improve the prognosis. In this review, we summarize the most relevant recent publications for the diagnosis, evaluation of disease activity and adequate management of patients with linear scleroderma.

RECENT FINDINGS

There are specific clinical features that indicate activity in LoS; dermoscopy and Wood's lamp may be useful. Summarizing, scoring methods seem to provide the most adequate assessment of LoS; but several biomarkers that correlate with activity have been studied: E-selectin and IL-2 receptor, CD34+ dermal dendritic cells and Th/Th1 immunophenotype with decreased T helper (Th2), T regulatory (Tregs), B and natural killer (NK) cells. Recent studies propose hydroxychloroquine monotherapy and tocilizumab as potential therapeutic options.

SUMMARY

Clinical evaluation, both physical exam and history, is the most important aspect in diagnosing and assessing activity of linear scleroderma. Clinical scoring methods may be most useful for evaluation of activity; eventually, other biomarkers could be relevant in clinical practice. For most patients with linear scleroderma, the first choice of treatment is methotrexate, but physical therapy, plastic surgery and/or orthopedic management are key to improve residual limitations and quality of life. VIDEO ABSTRACT: http://links.lww.com/MOP/A35.

Autoantibodies in Morphea: An Update

Skin autoimmune conditions belong to a larger group of connective tissue diseases and primarily affect the skin, but might also involve underlying tissues, such as fat tissue, muscle, and bone. Autoimmune antibodies (autoantibodies) play a role in autoimmune skin diseases, such as localized scleroderma also termed morphea, and systemic scleroderma, also called systemic sclerosis (SSc). The detailed studies on the biological role of autoantibodies in autoimmune skin diseases are limited. This results in a few available tools for effective diagnosis and management of autoimmune skin diseases. This review aims to provide an update on the detection and most recent research on autoantibodies in morphea. Several recent studies have indicated the association of autoantibody profiles with disease subtypes, damage extent, and relapse potential, opening up exciting new possibilities for personalized disease management. We discuss the role of existing autoantibody tests in morphea management and the most recent studies on morphea pathogenesis. We also provide an update on novel autoantibody biomarkers for the diagnosis and study of morphea.