Immature myeloid DC such as Langerhans cells in the mucosal epithelium and interstitial DC in the subepithelial mucosal tissues are thought to be the first cell types that contact with HIV-1, which exploits the biology of DCs to spread the infection to HIV-1-specific and HIV-1-nonspecific CD4 T cells[29]–[31]. The gene discussed is CD4; the disease is infection.