Longitudinal study of patients with antimelanoma differentiation-associated gene 5 antibody-positive dermatomyositis-associated interstitial lung disease

The role of nailfold video-capillaroscopy in the assessment of dermatomyositis

OBJECTIVES

The clinical manifestations of dermatomyositis (DM) are diverse, nailfold video-capillaroscopy (NVC) can reflect microangiopathy, a process believed to contribute significantly to the clinical manifestations of DM. We aimed to explore the distinctive alterations and implications of nailfold capillary for evaluating disease progression in individuals with DM.

METHODS

We gathered clinical data from 76 DM patients who underwent NVC in the Affiliated Hospital of Nantong University between September 2017 and September 2022. Additionally, we recruited 26 anti-synthase antibody syndrome (ASS) patients and 33 systemic sclerosis (SSc) patients as controls. Utilizing an unsupervised machine learning method (hierarchical clustering analysis) to categorized patients based on NVC results and compared clinical characteristics and survival outcomes. The follow-up period ended in December 2022.

RESULTS

Anomalous NVC patterns were detected in 73.7% of the 76 DM patients and manifested as diminished capillary density and abnormal capillary morphology. Patients displaying abnormal NVC findings exhibited a significantly higher prevalence of Raynaud's phenomenon and a greater likelihood of being managed with triple combination therapy. Compared with SSc patients, milder NVC changes were observed in patients with DM, nonetheless, NVC abnormalities were more prominent in DM patients when contrasted with individuals with ASS. Furthermore, the patients were classified into two different clusters according to NVC data. Patients in cluster 1 were more likely to develop interstitial lung disease (ILD). Survival outcomes did not differ significantly between the two clusters.

CONCLUSION

DM patients can experience varying degrees of aberrant NVC patterns, which can impact ILD risk and warrant clinical vigilance.

The Prospective Registry of MyositIS (PROMIS): I. Next-generation sequencing identifies HLA-DQA1 as a novel genetic risk of anti-MDA5 antibody-positive dermatomyositis

OBJECTIVES

Antimelanoma differentiation-associated gene 5-positive dermatomyositis (anti-MDA5+ DM) is a rare subtype of myositis with a poor prognosis and insufficient genetic understanding. Our study aimed to identify risk variants associated with anti-MDA5+ DM and to assess their correlation with clinical outcomes.

METHODS

We enrolled 231 anti-MDA5+ DM patients, 127 anti-MDA5⁻ DM patients, 1468 patients with non-DM rheumatic disease, and 1027 healthy controls, with an additional 51 anti-MDA5+ DM patients for validation. Whole-exome sequencing was used to identify human leukocyte antigen (HLA) alleles, amino acids, and single nucleotide polymorphisms (SNPs) in major histocompatibility complex (MHC) and non-MHC regions. Association studies were performed to identify genetic variants associated with anti-MDA5+ DM by comparing different sets of control groups. A clinical association study was conducted to further explore the influence of genetic factors on clinical manifestations.

RESULTS

Two novel genetic risks, HLA-DQA1*06:01 and HLA-DQB1*06:09, were significantly associated with anti-MDA5+ DM in both the discovery and validation cohorts. HLA-DQA1*06:01 was particularly prevalent in anti-MDA5+ DM (20.4%) compared with anti-MDA5⁻ DM (6.69%) and non-DM rheumatic disease (5.93%). Besides, the strongest associated amino acid was HLA-DQα1:69 (P = 3.27 × 10-11), and 1 SNP in the ARHGAP22 gene (rs76208937) showed suggestive significance (P = 7.99 × 10-6). In addition, HLA-DQA1*06:01 was linked to acute rapidly progressive interstitial lung disease (P < .001), elevated levels of lactate dehydrogenase (P = .026), and death (P = .049) in patients with anti-MDA5+ DM.

CONCLUSIONS

HLA-DQA1*06:01 is a new genetic and prognostic factor for anti-MDA5+ DM, potentially serving as a biomarker for early diagnosis and intervention.

MDA5 protein mediating persistent ER stress/unfolded protein response contributes to endothelial-mesenchymal-transition of lung microvascular endothelial cell in dermatomyositis

BACKGROUND

Dermatomyositis (DM) is an idiopathic inflammatory myopathy. Anti-MDA5 antibody positive DM (MDA5 + DM) is a distinct subtype of the disease. The model of anti-MDA5 antibody positive DM has been already reported. However, the detailed role and mechanism of MDA5 in vascular damage was still poorly understood.

METHODS

Clinical information was retrospectively collected, and a total of 127 DM patients were enrolled. Serum from DM patients and control subjects was used to treat mouse lung microvascular endothelial cells (MVECs) to investigate vascular changes. Western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence staining, immunoprecipitation, protein mass spectrometry, flow cytometry and bioinformatics analysis were used.

RESULTS

Firstly, clinical data analysis revealed that vascular damage and interstitial lung disease (ILD) was correlated with anti-MDA5 antibody in DM patients. Then, serum from patients was used to treat mouse lung MVECs. Serum from MDA5 + DM patients induced endothelial-mesenchymal-transition (EndMT) in MVECs, and the EndMT in MVECs was mediated by TRB3/ERK/Snai-1 pathway. Next, increased-TRB3 was confirmed induced by persistent ER stress/unfolded protein response (UPR). Notably, persistent ER stress/UPR resulted from MDA5 protein binding with PERK. At last, T cell-derived IFN-β was found to induce MDA5 expression in DM patients.

CONCLUSION

MDA5 protein mediating persistent ER stress/UPR contributed to EndMT in vascular endothelial cells, which should be involved in MDA5 + DM related ILD.

Short-term efficiency of plasma exchange in combination with immunosuppressants and/or biologics in the treatment of idiopathic inflammatory myopathy with rapidly progressive interstitial lung disease: a systematic review and meta-analysis

OBJECTIVE

Rapidly progressive interstitial lung disease (RP-ILD) is a frequent and serious manifestation of idiopathic inflammatory myopathy (IIM) associated with poor outcomes. Plasma exchange (PE) can quickly remove pathogenic substances from the blood. Therefore, PE may be efficacious in IIM patients who have elevated levels of autoantibodies, cytokines and chemokines, fighting for time for immunosuppressive therapy. However, the value of adding PE to immunosuppressants remains unclear. The purpose of this study was to determine the short-term outcomes, including the survival rate at 6 months and change of the laboratory data, of PE in combination with immunosuppressants and/or biologics in the treatment of IIM-RP-ILD.

METHODS

We searched PubMed, Embase and Cochrane Library to find reports of interest published from inception to March 4, 2024. STATA 15.1 was used for data analysis. A fixed or random-effects model with inverse-variance weighting was used to estimate the pooled risk ratio (RR) and 95% confidence interval (CI).

RESULTS

Two hundred and thirty studies were identified. Eleven studies, including five retrospective cohort studies, four case-control studies and two case series, were included. PE was performed on 114 patients. The survival rate at 6 months was 80% (95%CI = 64%-92%), with moderate heterogeneity (I2=63.45%, p < 0.05). Moreover, the 6-month survival rate was significantly better in the PE group than in the non-PE group (RR, 1.34; 95% CI = 1.05-1.71, I2=30.7%; p = 0.194). ILD-related serum markers, including ferritin, KL-6 and anti-MDA-5 antibody titres, were significantly suppressed by a series of PE treatments (p < 0.05).

CONCLUSION

The application of PE therapy plus treatment with corticosteroids, immunosuppressants and/or biologics was effective for patients with IIM-RP-ILD. PE may have additional supportive effect in intractable disease.

Anti-MDA5 antibody-positive dermatomyositis: pathogenesis and clinical progress

Anti-melanoma differentiation-associated protein 5 (MDA5) antibody-positive dermatomyositis (MDA5-DM) is a subtype of dermatomyositis. Although the aetiology and pathology remain unclear, increasing evidence suggests that viral infection is a potential trigger of MDA5-DM. Multiple factors, including T cells, B cells, neutrophils and macrophages, are implicated in the pathophysiology of MDA5-DM. Distinctive skin rashes, rapidly progressive interstitial lung disease, peripheral lymphopenia and elevated serum ferritin levels are the most prominent clinical and laboratory features of MDA5-DM. Concomitant infection is a common complication of MDA5-DM. The proper evaluation of patients with MDA5-DM requires knowledge of the disease heterogeneity and clinical course variability. Several biomarkers, including serum levels of anti-MDA5 antibodies and biomarkers related to macrophage activation, have been identified as useful tools for monitoring disease activity and prognosis. MDA5-DM shows a poor response to conventional glucocorticoid and immunosuppressant therapy and has a poor overall prognosis. Therefore, there is an urgent need to explore the key pathogenic mechanisms of MDA5-DM and develop novel therapeutic options for patients. This Review discusses recent clinical progress and pathogenic findings of MDA5-DM.

Transcriptomic profiling and longitudinal study reveal the relationship of anti-MDA5 titer and type I IFN signature in MDA5+ dermatomyositis

Objective

This study aimed to investigate the relationship between anti-MDA5 titer and type I IFN signature in patients with MDA5+ DM.

Methods

We explored the transcriptome profiling of PBMCs in MDA5+ DM patients with high-titer of antibody at disease onset or relapse and normal low-titer after treatment and healthy donors. Subsequently, we revealed the dynamic relationship between serum type I IFN scores and antibody titers.

Result

Differentially expressed genes in MDA5+ DM patients were enriched for related pathways and biological functions linked to viruses and cytokines compared to healthy donors. Similar differences remained pooled between the high-titer and low-titer group, and type I-specific interferon response genes showed upregulation in high-titer group. Significant correlations were found between anti-MDA5 titers and type I IFN scores (r = 0.50, P< 0.001). Contemporaneous anti-MDA5 titers revealed to be significantly higher in the group with ultra-high type I IFN scores (vs. high group, P = 0.027; vs. low group, P< 0.001). Longitudinal assessment of type I IFN scores and anti-MDA5 titers, including pre- and post-treatment changes at initial diagnosis and dynamic changes during treatment, presented an asynchrony between the two parameters in response to treatment.

Conclusion

Anti-MDA5 antibody titers correlated with type I IFN signature in patients with MDA5+ DM and they both changed dynamically but not synchronously over the course of treatment.