Article

Muscle inflammation and MHC class I up-regulation in muscular dystrophy with lack of dysferlin: an immunopathological study.

Department of Neuromuscular Diseases, Istituto Nazionale Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy.
Journal of Neuroimmunology (impact factor: 2.96). 10/2003; 142(1-2):130-6. pp.130-6
Source: PubMed

ABSTRACT Muscle inflammation is characteristic of inflammatory myopathies but also occurs in muscular dystrophy with lack of the sarcolemmal protein dysferlin. We quantified inflammatory cells and major histocompatibility complex (MHC) expression in muscle from 10 patients with dysferlinopathy. Infiltrating cells were always present although numbers varied considerably; macrophages were more common than T cells, T cytotoxicity was absent, and MHC class I was overexpressed on muscle fibers. These findings differ from polymyositis (PM) but are closely similar to those in SJL/J mice (which lack dysferlin) and emphasize the relationship between absence of dysferlin and immune system abnormalities in muscle.

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Keywords

10 patients
 
common
 
dysferlinopathy
 
immune system abnormalities
 
Infiltrating cells
 
inflammatory cells
 
inflammatory myopathies
 
macrophages
 
major histocompatibility complex
 
MHC
 
MHC class
 
muscle fibers
 
Muscle inflammation
 
muscular dystrophy
 
numbers varied
 
polymyositis
 
sarcolemmal protein dysferlin
 
SJL/J mice
 
T cells
 
T cytotoxicity