chlorogenic acid and alum synergistically enhance cellular and humoral immunity against heat-killed salmonella typhimurium vaccine

Chlorogenic acid (cga), a naturally occurring polyphenolic compound, is present in various plants, notably green coffee beans. this study aimed to evaluate the impact of combining cga with alum on cellular and humoral immunity after vaccination with heat-killed salmonella typhimurium (hkst). male balb/c mice were given two administrations of the hkst vaccine, either with or without alum, cga, or both, spaced two weeks apart. two weeks after the final immunization, immune responses and protection levels against s. typhimurium were assessed. the combination of alum and cga improved the hkst vaccine s capacity to promote lymphocyte proliferation, delayed-type hypersensitivity responses, and antibody levels, as well as to shift the igg2a/igg1 ratio toward igg2a. these results were associated with a greater th1 immune response and enhanced protective immunity against s. typhimurium. additionally, the group treated with the combined adjuvant exhibited an increased survival rate following exposure to the acute dose of s. typhimurium and a decreased bacterial load in the liver after exposure to the subacute dose of s. typhimurium, compared to other immunization strategies the combination of alum and cga considerably enhanced cellular and humoral immunity following hkst immunization.