Dietary Influence on Antinuclear Antibodies and Cell-Mediated Immunity in NZB Mice

The influence of two different commerical diets on immune parameters of 8–11-month-old New Zealand Black (NZB) female mice has been presented. A diet relatively high in fat and low in protein favored increase of body weight, but also increased the propensity of NZB mice to develop anemia, leukocytosis, and reticulocytosis. The higher fat diet also increased the severity of Coombs positivity and resulted in apparently larger amounts of immunoglobulins, especially IgGj and IgA autoantibodies, on red cell surfaces than did the lower fat diet fed to NZB mice. The sera of mice fed a higher fat diet contained a greater titer of antibodies to deoxyribonucleoprotein. The higher fat diet was also associated with a greater deficiency of cellular cytotoxicity to mammary adenocarcinoma and sarcoma I cells, and with a lower capacity to induce graft-vs.-host reactions. Production of serum blocking factors against sarcoma I and hemagglutinating antibody response with SRBC in old NZB mice did not seem to be influenced by diet. These changes in the kinetics of the cellular and humoral immune response associated with diet suggest that acceleration or delay of the involution of the lymphoid system in NZB mice may be attributed to variations in diet. This finding deserves extensive and direct analysis.