Modulation by Zinc of the in Vitro Antibody Response to T-Dependent and T-Independent Antigens

Abstract

The influence of zinc on the in vitro antibody response to antigen or mitogen stimulation was studied by adding various concentrations of ZnCl₂ to cultures of spleen cells stimulated with sheep erythrocytes, trinitrophenyl-lipopolysaccharide or with the polyclonal B cell activator E. coli lípopolysac-charide (LPS). Addition of ZnCl₂ in concentrations ranging from 10^-8 or 10^-7 to 10^-5 M increased the specific antibody response to antigens or the polyclonal antibody synthesis induced by stimulation with LPS, when the response of the assayed population in the control cultures without ZnCl₂ was low, as observed in cultures without 2-mercaptoethanol (2-ME). However, in cultures supplemented with 2-ME, the potentiating effect of ZnCl₂ diminished or disappeared or even the antibody response was inhibited. Higher concentrations of ZnCl₂ markedly depressed (5 × 10^-5 M) or abolished (10^-4)the in vitro induced antibody response in all cultures. The various mechanisms which could mediate the effects of zinc are discussed.