Kiwifruit extract enhances markers of innate and acquired immunity in a murine model

The present study examined the effects of a kiwifruit (Actinidia chinensis and Actinidia deliciosa) extract on immune response in BALB/c mice. The effects were investigated using cholera vaccine (11 days duration) and diphtheria/tetanus toxoid vaccine (29 days duration) models. Mice were given either test (standard diet incorporated with kiwifruit extract) or control diets ad libitum throughout the respective experimental periods. At the end, blood, spleen and intestinal fluids were collected for determination of cell proliferation, specific antibody responses, cytokine production, phagocytosis, and natural killer cell activity. The kiwifruit extract significantly enhanced (p<0.05) specific intestinal mucosal and serum antibody responses to the vaccines and promoted interferon- and natural killer cell activitiy. No significant (p>0.05) improvement was observed in proliferative cell response, phagocytic activity or interleukin-4 production. The overall results of the present study demonstrate the ability of a kiwifruit extract to enhance markers of innate and acquired immunity in the tested murine model.