Scleroderma: Possible Association with the C4 System — A Progress Report

Abstract

Scleroderma (progressive systemic sclerosis; PSS) is a systemic connective tissue disorder characterized by proliferative vascular lesions, obliterative microvascular lesions, and residual atrophy with fibrosis of multiple organs, e.g., skin, gastrointestinal tract, heart, lung, and kidney. The etiology is unknown. Immune mechanisms such as hyperimmunoglobulinemia, circulating immune complexes, anti-nuclear antibodies, mononuclear cell infiltrates in the skin, aberrant T cell subpopulations, and decreased lymphocyte transformation by nonspecific mitogens, though unspecific findings, have been described. Also, a scleroderma-like disease may occur in graft-versus-host reactions. Yet association studies of PSS with HLA region markers have revealed heterogeneous results. Associations with A9, B8, B27, B35, Dwl, and DR5 have been reported. In two investigations, no associations were found. Most recently, three C4B1QO,QO individuals were found among 17 patients with PSS, compared with three C4B*QO,QO individuals among 144 normal controls (P = 0.016 in Fisher’s test). The aim of the Workshop scleroderma study was to see whether this previous finding [3] could be confirmed.

This study was supported in part by a grant from Deutsche Forschungsgemeinschaft (Ri 164/16-1)