Effect of GM and non-GM soybeans on the immune system of BN rats and B10A mice

Subchronic animal feeding studies to examine the effect of glyphosate-toler ant soybeans, which contain the bacterial 5-enolpyruvylshikimate-3-phosphat e synthase from Agrobacterium sp. strain CP4, on the immune system were con ducted with BN rats and B10A mice. The studies were designed to compare the feeding value of a line of genetically modified glyphosate-tolerant soybea ns (GM soybeans) to that of closely-related and one-parent same cultivar (n on-GM soybeans). Heat-treated soybean meal was incorporated into the diets of the rats and mice at a concentration of 30%. The study duration was 15 w eeks. Growth, food intake and weights of the liver and the spleen mere comp ared between animals fed the non-GM and GM lines. The histopathology of the thymus, liver, spleen, mesenteric lymph node, Peyer's patches, and small i ntestine, and the production of soybean-specific IgE and IgG antibodies in the sera were also compared. Growth, feeding value, and the histopathology of immune-related organs showed no significant differences between animals fed GM and non-GM lines. The production of soybean-specific IgE was not det ected in the sera of either group, and the increase in soybean-specific IgG was identical in the GM and non-GM groups. No immunotoxic activity was fou nd in GM-soybean-fed rats or mice.