MHC class I, MHC class II and intercellular adhesion molecule-1 (ICAM-1) expression in inflammatory myopathies.
We investigated the relationship between the MHC-I, MHC-II and intercellular adhesion molecule-1 (ICAM-1) expression on myofibres and the presence of inflammatory cells in muscle specimens of 18 patients with inflammatory myopathies (nine polymyositis, seven dermatomyositis, two inclusion body myositis). We observed MHC-I expression in muscle fibres, infiltrating mononuclear cells and endothelial cells in every specimen. In seven patients, some muscle fibres were MHC-II-positive for the DR antigen, while the DP and DQ antigens were absent. ICAM-1 expression, detected in seven patients, was found in clusters of myofibres, associated with a marked MHC-I positivity and a widespread mononuclear infiltration. Most of the ICAM-1-positive fibres were regenerating fibres. Furthermore, some fibres expressed both ICAM-1 and DR antigens near infiltrating cells. This finding could support the hypothesis that myofibres may themselves be the site of autosensitization.
Bartoccioni
E
E
Institute of General Pathology, Catholic University, Rome, Italy.
Gallucci
S
S
Scuderi
F
F
Ricci
E
E
Servidei
S
S
Broccolini
A
A
Tonali
P
P
D015703:Antigens, CD / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D019002:CD56 Antigen; D015815:Cell Adhesion Molecules / Q000032:analysis*; D003882:Dermatomyositis / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000032:analysis*; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1; D009132:Muscles / Q000276:immunology; D009220:Myositis / Q000276:immunology*; D017285:Polymyositis / Q000276:immunology
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D019002:CD56 Antigen; D015815:Cell Adhesion Molecules; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D018799:Intercellular Adhesion Molecule-1