Gestational zinc requirement of the A/J mouse: Effects of a marginal zinc deficiency on inutero B-cell development

Abstract

A series of studies were initiated to define the effects of suboptimal zinc intake on in utero development of the immune system using the A/J mouse. Dams were fed a biotin-fortified egg white diet containing 1.3, 2.7, 3.8, 6.2, 10 or 30 μg Zn/g (control) from days 0 to 18 of gestation. It was found that a dietary zinc level of 10 μg Zn/g was adequate for gestation. Dams fed 3.8 μg Zn/g had a modest decrease in weight gain and serum zinc levels; by day 18 fetal body weights were 86% the weight of control fetuses. Thus, the 3.8 μg Zn/g diet was judged to be marginal and was subsequently used to study B-cell development in the fetal liver. Day 18 fetal liver cells (FLC) were prepared from groups receiving adequate (30 μg Zn/g), adequate but restricted-fed (30 μg Zn/g) and marginal levels (3.8 μg Zn/g) of dietary zinc for adoptive transfer to normal, irradiated adult hosts. In response to a T-cell independent antigen (TI), the recipients which received FLC from the marginal or restricted-fed groups produced 49% and 90% respectively as many antibody producing cells per spleen as recipients which received FLC from normal fetuses. The results indicate that B-cell development in utero was significantly altered by a marginal zinc deficiency.