50PInflammatory cells immunophenotyping, MHC1 and type1 interferon proteins expression in myositis and hereditary muscle diseases with inflammatory cell infiltration: a north African study

IF 2.8 4区医学 Q2 CLINICAL NEUROLOGY

Neuromuscular Disorders Pub Date : 2025-09-01 DOI:10.1016/j.nmd.2025.105513

E. Farhat , A. Ben Hmid , M. Ben Ahmed

{"title":"50PInflammatory cells immunophenotyping, MHC1 and type1 interferon proteins expression in myositis and hereditary muscle diseases with inflammatory cell infiltration: a north African study","authors":"E. Farhat , A. Ben Hmid , M. Ben Ahmed","doi":"10.1016/j.nmd.2025.105513","DOIUrl":null,"url":null,"abstract":"<div><div>Muscle biopsy (MB) is an important tool to help differentiate autoimmune inflammatory myopathies (AIM) from hereditary muscular diseases (HMD). HMD may sometimes show inflammatory cell infiltration mimicking AIM. The usefulness of immunohistochemical (IHC) stains of the major histocompatibility complex class 1 (MHC1) become controversial, as the possibility of their upregulation in some HMD. More sensitive markers of AIM are recently used such as myxovirus resistance A (MxA) and interferon-stimulated gene 15 (ISG15), a type1 interferon-inductible (IFN1) proteins. This study aims to compare the morphological and the immunophenotype patterns of the inflammatory cells, versus the MHC1 and IFN1 proteins’ expression in different subsets of AIM and HMD. We selected samples of 85 patients diagnosed with AIM including cases with overlap myositis, dermatomyositis, immune-mediated necrotizing myopathy and inclusion body myositis; and HMD including patients with muscular dystrophies and metabolic myopathies. The inclusion criterion was the presence of inflammatory infiltrate on MB. We characterized the IHC expressions of the inflammatory cells (CD4, CD8, CD20, CD68), MHC1, and IFN1-inductible proteins (MxA and ISG15). There was no statistically significant difference in the types of infiltrating cells between the two groups except for the CD68+ T cells, most abundant in the HMD group (p<0,005). MHC1 was expressed in muscle fibers of AIM and HMD without significant difference between the two groups. The sarcoplasmic expressions of MxA and ISG15 were highly and significantly prevalent in DM patients (80%; p<0,005). Our study demonstrated the limitation of inflammatory cells immunophenotyping and the IHC of the MHC1 in the differential diagnosis of AIM and HMD with inflammatory changes. It also enables us to confirm that IFN1-inductible proteins are much accurate IHC markers of AIM especially in the DM subgroup.</div></div>","PeriodicalId":19135,"journal":{"name":"Neuromuscular Disorders","volume":"53 ","pages":"Article 105513"},"PeriodicalIF":2.8000,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Neuromuscular Disorders","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0960896625002408","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CLINICAL NEUROLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Muscle biopsy (MB) is an important tool to help differentiate autoimmune inflammatory myopathies (AIM) from hereditary muscular diseases (HMD). HMD may sometimes show inflammatory cell infiltration mimicking AIM. The usefulness of immunohistochemical (IHC) stains of the major histocompatibility complex class 1 (MHC1) become controversial, as the possibility of their upregulation in some HMD. More sensitive markers of AIM are recently used such as myxovirus resistance A (MxA) and interferon-stimulated gene 15 (ISG15), a type1 interferon-inductible (IFN1) proteins. This study aims to compare the morphological and the immunophenotype patterns of the inflammatory cells, versus the MHC1 and IFN1 proteins’ expression in different subsets of AIM and HMD. We selected samples of 85 patients diagnosed with AIM including cases with overlap myositis, dermatomyositis, immune-mediated necrotizing myopathy and inclusion body myositis; and HMD including patients with muscular dystrophies and metabolic myopathies. The inclusion criterion was the presence of inflammatory infiltrate on MB. We characterized the IHC expressions of the inflammatory cells (CD4, CD8, CD20, CD68), MHC1, and IFN1-inductible proteins (MxA and ISG15). There was no statistically significant difference in the types of infiltrating cells between the two groups except for the CD68+ T cells, most abundant in the HMD group (p<0,005). MHC1 was expressed in muscle fibers of AIM and HMD without significant difference between the two groups. The sarcoplasmic expressions of MxA and ISG15 were highly and significantly prevalent in DM patients (80%; p<0,005). Our study demonstrated the limitation of inflammatory cells immunophenotyping and the IHC of the MHC1 in the differential diagnosis of AIM and HMD with inflammatory changes. It also enables us to confirm that IFN1-inductible proteins are much accurate IHC markers of AIM especially in the DM subgroup.

查看原文本刊更多论文

炎性细胞免疫表型、MHC1和1型干扰素蛋白在肌炎和具有炎性细胞浸润的遗传性肌肉疾病中的表达：一项北非研究

肌肉活检（MB）是帮助区分自身免疫性炎症性肌病（AIM）和遗传性肌肉疾病（HMD）的重要工具。HMD有时可能表现出类似AIM的炎症细胞浸润。主要组织相容性复合体1类（MHC1）的免疫组化（IHC）染色的有效性受到争议，因为它们可能在某些HMD中上调。最近使用了更敏感的AIM标记物，如黏液病毒抗性A （MxA）和干扰素刺激基因15 (ISG15)，一种1型干扰素诱导（IFN1）蛋白。本研究旨在比较炎症细胞的形态学和免疫表型模式，以及MHC1和IFN1蛋白在AIM和HMD不同亚群中的表达。我们选取了85例诊断为AIM的患者，包括重叠性肌炎、皮肌炎、免疫介导的坏死性肌病和包涵体肌炎；和HMD，包括肌肉萎缩症和代谢性肌病患者。纳入标准是MB上是否存在炎症浸润。我们表征了炎症细胞（CD4、CD8、CD20、CD68）、MHC1和ifn1诱导蛋白（MxA和ISG15）的IHC表达。两组间浸润细胞类型差异无统计学意义，除CD68+ T细胞外，HMD组浸润细胞最多（p< 0.005）。MHC1在AIM和HMD的肌纤维中表达，两组间差异无统计学意义。MxA和ISG15的肌浆表达在DM患者中高度且显著流行（80%;p< 0.005）。我们的研究证明了炎症细胞免疫分型和MHC1的免疫组化在AIM和HMD伴炎症改变的鉴别诊断中的局限性。这也使我们确认ifn1诱导蛋白是AIM的准确IHC标记物，特别是在DM亚组中。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Neuromuscular Disorders 医学-临床神经学

CiteScore

4.60

自引率

3.60%

发文量

543

审稿时长

53 days

期刊介绍： This international, multidisciplinary journal covers all aspects of neuromuscular disorders in childhood and adult life (including the muscular dystrophies, spinal muscular atrophies, hereditary neuropathies, congenital myopathies, myasthenias, myotonic syndromes, metabolic myopathies and inflammatory myopathies). The Editors welcome original articles from all areas of the field: • Clinical aspects, such as new clinical entities, case studies of interest, treatment, management and rehabilitation (including biomechanics, orthotic design and surgery). • Basic scientific studies of relevance to the clinical syndromes, including advances in the fields of molecular biology and genetics. • Studies of animal models relevant to the human diseases. The journal is aimed at a wide range of clinicians, pathologists, associated paramedical professionals and clinical and basic scientists with an interest in the study of neuromuscular disorders.