Vitelli-Avelar DM, Sathler-Avelar R, Massara RL, Borges JD, Lage PS, et al. (2006) Are increased frequency of macrophage-like and natural killer (NK) cells, together with high levels of NKT and CD4+CD25high T cells balancing activated CD8+ T cells, the key to control Chagas' disease morbidity? The gene discussed is CD4; the disease is Chagas disease.