Mechanistic perspectives on anti-aminoacyl-tRNA synthetase syndrome

Myositis-specific and myositis-associated autoantibodies: their clinical characteristics and potential pathogenic roles

In recent years, various myositis-specific and myositis-associated autoantibodies have been identified in idiopathic inflammatory myopathies, including dermatomyositis (DM), anti-synthetase syndrome (ASS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM). These autoantibodies exhibit unique characteristics in terms of organ involvement, severity, and treatment response, making their understanding crucial for accurate diagnosis and effective therapy. This review provides a comprehensive overview of the clinical features of recently discovered myositis-specific and associated autoantibodies, while exploring their potential roles in the pathogenesis and exacerbation of myositis. Key findings include the production of anti-TIF1γ antibodies in model mice, the upregulation of Mi2-related genes in anti-Mi2 antibody-positive dermatomyositis muscle tissue, and Jo-1 antigen-induced T cell activation, shedding light on whether disease mechanisms are driven by autoantibodies or autoantigens.

Compartmentalization into Outer and Inner Shells of Hollow Nanospheres for Antibiosis Based on Chemistry and Physical Damages

There is a substantially ascending demand for nonantibiotic strategies to overcome the resistance of bacterial infections. Here, the discovery of a distinctive antibacterial structure is reported. The novel structure of nanoparticle strategy is proposed for appreciable bacteria killing by the smart design of the delayed addition of crosslinkers into the reaction mixture. [2-(methacryloyloxy)ethyl]trimethylammonium chloride solution (MTCl), a water-soluble ionic liquid (IL), has narrow-size material distribution, good whiteness, and high weather resistance. The quaternary ammonium salt is utilized to efficiently permeate cell membranes through electrostatic interaction, accordingly, boasting a beneficiary of antibacterial properties. More importantly, it allows bacteria to attach the nanomaterials easily, especially the double-shelled nanosphere. In light of the introduction of 9-amino(9-deoxy)ep-quinine (QNNH2) on its inner shell, it blocks the nucleic acid and glucose metabolism in bacteria, which is betterment of the antibacterial activity of double-shelled structure nanoparticle compared to other structure of nanomaterials. This physical/chemical/biological triple antibacterial process eliminates the need for traditional antibiotics, and the fabrication strategies and material properties described here provide insights into the design of antibacterial nanomaterials based on chemical and physical effects.

The Clinical Value of the Neutrophil-to-Lymphocyte Ratio, the C-Reactive Protein-to-Albumin Ratio, the Systemic Inflammatory Index, and the Systemic Inflammatory Response Index in Patients with the Anti-Synthetase Syndrome

Objective

There are no studies examining the role of the neutrophil-to-lymphocyte ratio (NLR), the C-reactive protein-to-albumin ratio (CAR), the systemic inflammatory index (SII), and the systemic inflammatory response index (SIRI) in anti-synthetase syndrome (ASS). We aim to compare NLR, CAR, SII, and SIRI in ASS and dermatomyositis/polymyositis (DM/PM), as well as to examine potential correlations between NLR, CAR, SII, and SIRI and clinical features and laboratory parameters in ASS.

Methods

Retrospective collection of data from 111 patients with ASS and 175 patients with DM/PM. A Spearman rank correlation analysis was utilized to analyze the correlation between NLR, CAR, SII, and SIRI and inflammatory indexes. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value. Univariate logistic regression analysis was performed to assess risk factors for interstitial lung disease (ILD).

Results

Compared with DM/PM, NLR, CAR, SII, and SIRI were significantly greater in ASS patients (p < 0.05). NLR, CAR, SII, and SIRI were correlated with albumin, lactic dehydrogenase (LDH), C-reactive protein (CRP), ferritin, white blood cell (WBC), platelets, and myositis disease activity assessment visual analog scales (MYOACT) score (p < 0.05). The ROC curves analysis showed that NLR, SII, and SIRI were all highly predictive of the occurrence of ASS. Comparisons based on clinical characteristics showed elevated levels of NLR, CAR, SII, and SIRI in ASS patients with ILD, fever, and infection (p < 0.05). Univariate logistic regression analysis revealed that NLR, CAR, and SII were significant risk factors for ASS-ILD (p < 0.05).

Conclusion

The levels of NLR, CAR, SII, and SIRI were higher in ASS than in DM/PM and correlated with disease activity and specific clinical features. NLR, CAR, SII, and SIRI may be an aid in differentiating ASS from DM/PM and maybe promising biomarkers for ASS.

Disease association and therapeutic routes of aminoacyl-tRNA synthetases

Aminoacyl-tRNA synthetases (ARSs) are enzymes that catalyze the ligation of amino acids to tRNAs for translation. Beyond their traditional role in translation, ARSs have acquired regulatory functions in various biological processes (epi-translational functions). With their dual-edged activities, aberrant expression, secretion, and mutations of ARSs are associated with human diseases, including cancer, autoimmune diseases, and neurological diseases. The increasing numbers of newly unveiled activities and disease associations of ARSs have spurred interest in novel drug development, targeting disease-related catalytic and noncatalytic activities of ARSs as well as harnessing ARSs as sources for biological therapeutics. This review speculates how the translational and epi-translational activities of ARSs can be related and describes how their activities can be linked to diseases and drug discovery.

Phenotypic Profiles Among 72 Caucasian and Afro-Caribbean Patients with Antisynthetase Syndrome Involving Anti-PL7 or Anti-PL12 Autoantibodies

OBJECTIVES

Antisynthetase syndrome (ASyS) is a rare autoimmune disease. We aimed to determine clinical, biological, radiological, and evolutive profiles of ASyS patients with anti-PL7 or anti-PL12 autoantibodies.

METHODS

We performed a retrospective study that included adults with overt positivity for anti-PL7/anti-PL12 autoantibodies and at least one Connors' criterion.

RESULTS

Among 72 patients, 69% were women, 29 had anti-PL7 and 43 anti-PL12 autoantibodies, median age was 60.3 years, and median follow-up period was 52.2 months. At diagnosis, 76% of patients had interstitial lung disease, 61% had arthritis, 39% myositis, 25% Raynaud's phenomenon, 18% mechanic's hands, and 17% had fever. The most frequent pattern on initial chest computed tomography was non-specific interstitial pneumonia and 67% had fibrosis at last follow-up. During follow-up, 12 patients had pericardial effusion (18%), 19 had pulmonary hypertension (29%), 9 (12.5%) had neoplasms, and 14 (19%) died. Sixty-seven patients (93%) received at least one steroid or immunosuppressive drug. Patients with anti-PL12 autoantibodies were younger (p=0.01) and more frequently exhibited anti-SSA autoantibodies (p=0.01); patients with anti-PL7 autoantibodies had more severe weakness and higher maximum creatine kinase levels (p=0.03 and 0.04, respectively). Initial severe dyspnoea was more common in patients from the West Indies (p=0.009), with lower predicted values of forced vital capacity, forced expiratory volume in 1s, and total lung capacity (p=0.01, p=0.02, p=0.01, respectively) contributing to a more severe 'respiratory' initial presentation.

CONCLUSIONS

The high mortality and significant numbers of cardiovascular events, neoplasms and lung fibrosis in anti-PL7/12 patients justify close monitoring and question addition of antifibrotic drugs.

Physiological and engineered tRNA aminoacylation

Aminoacyl-tRNA synthetases form the protein family that controls the interpretation of the genetic code, with tRNA aminoacylation being the key chemical step during which an amino acid is assigned to a corresponding sequence of nucleic acids. In consequence, aminoacyl-tRNA synthetases have been studied in their physiological context, in disease states, and as tools for synthetic biology to enable the expansion of the genetic code. Here, we review the fundamentals of aminoacyl-tRNA synthetase biology and classification, with a focus on mammalian cytoplasmic enzymes. We compile evidence that the localization of aminoacyl-tRNA synthetases can be critical in health and disease. In addition, we discuss evidence from synthetic biology which made use of the importance of subcellular localization for efficient manipulation of the protein synthesis machinery. This article is categorized under: RNA Processing Translation > Translation Regulation RNA Processing > tRNA Processing RNA Export and Localization > RNA Localization.