CD8A and coccidiosis: In another study in broiler chickens, a blend of carvacrol, cinnamaldehyde, and capsicum oleoresin was useful in promoting cell-mediated immunity leading to an increase in natural killer T cells, CD4+ (helper) T cells, CD8+ (cytotoxic) T cells, macrophages, and cytokines such as Interleukins-6 and interferon-γ that enhanced the host immunity against coccidiosis by stimulating both the innate and the adaptive (humoral) immune response [11].