INFLUENCE OF DIETARY RESTRICTION AND SOYBEAN SUPPLEMENTATION ON THE GROWTH OF A MURINE LYMPHOMA AND HOST IMMUNE FUNCTION

A comparative study was made to reveal the influence of caloric restri ction with or without soyabean in the diet on the growth of a murine l ymphoma, host survival, serum profile of vitamin A and E and immune st atus of the host. Caloric restriction delayed and inhibited tumour gro wth and improved host survival; inclusion of soyabean during restricti on enhanced this effect. Dietary restriction both in the absence and p resence of soyabean improved the proliferative response of peripheral blood lymphocytes. This was accompanied by increased cytolytic activit y of peritoneal macrophages and elevation in serum immunoglobulins (Ig G and IgM). Levels of vitamins A and E, which is found to be low in tu mour bearing animals, decreased further when maintained in the restric ted diet without soyabean, but was raised to normal levels following a ddition of soyabean in the diet. These observations imply that tumour growth is arrested possibly by insufficient nutrition available due to dietary restriction, for actively proliferating tumour cells and by i mprovement in host immune mechanism in the presence of soyabean in the diet.