Depressed lymphocyte responses to wheat germ agglutinin and other mitogens in treated coeliac disease patients

Abstract

Abstract This report investigates the possibility that inappropriate lymphocyte responses to wheat germ agglutinin (WGA), a mitogen found in wheat which influences proliferation of and immunoglobulin (Ig) synthesis by peripheral blood mononuclear cells (PBMC), may account for some of the immunological dysfunction noted in coeliac disease. The PBMC were prepared from healthy controls and 16 patients with coeliac disease who had received a gluten‐free diet for periods of 1 month to over 20 years. There was no difference in the proliferative responses of PBMC from the patients and normal subjects to optimal mitogenic concentrations of phytohaemagglutinin (PHA) or Concanavalin A (Con A), but the responses of the cells of the patients to pokeweed mitogen (PWM) and to a suboptimal concentration of Con A were reduced. The proliferative response induced by WGA in PBMC from treated coeliac patients was significantly depressed compared with controls. The synthesis of Ig by PWM‐stimulated PBMC, and the Con A induced suppression of this synthesis, was the same in cultures of PBMC from the patients or the controls. There was no difference in the effect of WGA on Ig synthesis between the patients and controls. It is concluded that there is no difference in the effect of WGA on Ig synthesis by PBMC from coeliac disease patients or controls, but that lymphocytes from coeliac disease patients proliferate poorly in response to WGA.