CD4 and infection: In the skin, Langerhans cells, conventional dendritic cells (DCs), macrophages (Mφs) and keratinocytes are believed to be the primary targets of infection, which can then spread to other organs through draining lymph nodes.2–4 In most individuals, DENV infection induces virus-specific Abs and CD4+ and CD8+ T cells, which provide protection against subsequent infection by the same serotype but only temporary cross-protection against different serotypes of DENV.1,4