CMV infection in patients with HIV/AIDS may be associated with increasing numbers of Tregs, suggesting that CMV infection promotes the production of Tregs; Tregs inhibit the production of mature dendritic cells and other antigen-presenting cells, contributing to CD4+ and CD8+ T lymphocyte dysfunction, which serves to aggravate the damage of cellular immune function, eventually leading to death. The gene discussed is CD4; the disease is cytomegalovirus infection.