Vacuolar myositis with expression of both MHC class I and class II antigens on skeletal muscle fibers.
We describe here a 10-year-old patient with high levels of serum IgE and inflammatory myopathy whose muscle fibers exhibit excessive autophagy. Previous studies have demonstrated surface expression of class I MHC antigens on muscle fibers from patients with inflammatory myopathy. The muscle fibers of this patients showed marked expression of both class I and class II MHC antigens. The reaction products were demonstrated not only on sarcolemma but also in and around some vacuoles. Both CD4-positive and CD8-positive T-lymphocytes were noted in inflammatory exudates surrounding these fibers but B-lymphocytes were rare. We hypothesize that myocyte expression of both class I and class II antigens may play a role in the pathogenesis of this new type of inflammatory myopathy.
Higuchi
I
I
Third Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Japan.
Nerenberg
M
M
Ijichi
T
T
Fukunaga
H
H
Arimura
K
K
Usuki
F
F
Kuriyama
M
M
Osame
M
M
D001327:Autoimmune Diseases / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D002648:Child; D006680:HLA Antigens / Q000032:analysis*; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007181:Inclusion Bodies, Viral; D008297:Male; D009132:Muscles / Q000276:immunology* / Q000473:pathology; D009220:Myositis / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D010587:Phagocytosis; D011239:Prednisolone / Q000627:therapeutic use; D014617:Vacuoles
D006680:HLA Antigens; D006684:HLA-DR Antigens; D007073:Immunoglobulin E; D011239:Prednisolone