Expression of 65-kd heat shock proteins in the inflammatory myopathies

✍ Scribed by Reinhard Hohlfeld; Dr Andrew G. Engel

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 368 KB
• Volume: 32
• Category: Article
• ISSN: 0364-5134
• DOI: 10.1002/ana.410320619

✦ Synopsis

In normal muscle, 65-kd heat shock proteins (hsp) were detected on capillary endothelial cells, the mural elements of larger vessels, and some intracellular organelles, probably mitochondria. In the inflammatory myopathies, the 65-kd hsp were detected on inflanunaxory cells, degenerating and regenerating fibers, and on many but not all nonnecrotic muscle fibers invaded by T cells.

The expression of the 65-kd hsp may be an immunenonspecific response to cellular "stress," but hsp determinants could possibly also serve as autoantigen(s) recognized by autoreactive T cells.

Hohlfeld R, Engel AG. Expression of 65-kd heat shock proteins in the inflammatory myopathies. Ann Neurol 1992;32:821-823 Heat shock proteins (hsp) constitute a heterogeneous family of molecules that serve important functions in the folding, assembly, and transport of cellular proteins 11-31. The majority of hsp are expressed constitutively in various cells [1-3]. In addition, many hsp are induced under conditions of stress including heat shock, nutritional deprivation, and on exposure to cytokines or inflammatory mediators {l-31. Hsp may serve as antigens recognized by T cells expressing either the common a / p or the uncommon $6 T-cell receptor [4-61. This has led to speculation that hsp might be involved in T-cell-mediated autoimmune reactions [4-61. In this communication, we document the distribution of 65-kd hsp in polymyositis, inclusion body myositis, dermatomyositis, and granulomatous myopathy. Materials and Methods Muscle specimens were used from 23 patients with inflammatory myopathies (polymyositis, 6 patients; inclusion body myositis, 6 patients; dermatomyositis, 6 patients; granulomatous myopathy, 5 patients) and from 2 subjects without mus-From the