CD4 and liver cancer: Additional studies demonstrated that KLT exhibited immunomodulatory activity by reducing the levels of the cytokines IFN-γ and IL-2, rescuing the levels of CD4+ T cells, and enhancing the cytotoxic activities of natural killer (NK) and CD8+ T cells in the serum of nude mice bearing human liver cancer HepG2 xenografts and stimulated the immune response by increasing the number of T cells and NK cells in the blood of patients with liver cancer (Huang et al., 2014).