The sterile protective immunity to malaria induced in humans by immunization with irradiated sporozoites is thought to be mediated by CD4+ and CD8+ T cells responding to malaria peptides expressed on the surface of hepatocytes or antigen presenting cells by secreting interferon-gamma (IFN-γ) and/or by cytotoxic responses, although anti-sporozoite antibodies may contribute [1-5]. Here, CD4 is linked to malaria.