Inhibition of denaturation of human gamma globulin by a mixture of L-histidine, L-cystine, and copper, and its clinical implication in rheumatoid arthritis.

A mixture of histidine, cystine, and copper mimicked gold thiomalate, N-ethylmaleimide, and p-chloro-mercuribenzoic acid in inhibiting sulfhydryl-disulfide interchange-mediated denaturation of human gamma globulin, bovine serum albumin, and diluted human serum. Measurable inhibitory effects were obtained with a mixture of physiologic concentrations of L-histidine, L-cystine, and copper. This work suggests a mechanism by which the hypohistidinemia of rheumatoid arthritis could contribute to the pathogenesis of the disease.