EFFECTS OF BILE-ACIDS AND LECTINS ON IMMUNOGLOBULIN PRODUCTION IN RATMESENTERIC LYMPH-NODE LYMPHOCYTES

We investigated the effect of bile acids either alone or in combinatio n with lectins on immunoglobulin (Ig) production in vitro of rat mesen teric lymph node (MLN) lymphocytes to examine their immunoregulatory a ctivities. Among free bile acids examined, chenodeoxycholic acid stimu lated IgE production by MLN lymphocytes and inhibited IgA production a t the concentration of 0.3 mM, whereas cholic and deoxycholic acids ex erted the comparable effect at 3 mM. Among conjugated bile acids, deox ycholic acid derivatives stimulated IgE production more strongly than cholic acid derivatives. On the other hand, free and conjugated bile a cids did not affect IgG production. The IgE production by MLN lymphocy tes was stimulated by concanavalin A and inhibited by pokeweed mitogen , and the effect of phytohemmagglutinin and lipopolysaccharide was mar ginal. These lectins did not affect IgA and IgG production by the lymp hocytes. In the presence of lectins, free bile acids affected IgE prod uction at 0.03 mM. These results suggest the possibility that bile aci d is a stimulant for food allergy.