Transplantation of skin grafts in rats fed plant protein wheat gluten.

ABSTRACT

The effects of diets containing low biologic value plant protein wheat gluten and the high biologic value protein casein on skin allograft survival were studied in growing Charles River (C.D. strain) rats. Five groups of weanling rats were fed 16% casein or gluten with or without supplementation with the amino acids L-lysine and L-threonine. Allografts were obtained from the hooded Lister strain. Autograft experiments were also performed. The skin bed and the allografts were prepared by round-punch biopsies, and the grafts were retained in situ by cellophane tape dressings. In the gluten-fed rats, no rejection of allografts was observed during the 45-day study period. In the casein-fed rats, a 90% rejection rate occurred on Days 10-14 after transplantation. The absence of rejection in gluten-fed rats may be explained by an impaired cellular immune response due to protein malnutrition. Supplementing the gluten diet with the essential amino acids L-lysine and L-threonine restored the rejection rate to that of the control rats. The cell-mediated immune response, as measured by in vitro stimulation of lymphocytes with the mitogen concanavalin A, was severely impaired by the gluten diet. These experiments indicate that low biologic value protein diet in the rat is associated with skin allograft acceptance, probably due to impairment of cell-mediated immunity.