CD4 and infection: Thus, trans infection could (1) be blocked by antibodies to CD4 and T cell accessory molecule CD80 [85], (2) be augmented by activated CD4+ T cells expressing CD40L [85], proinflammatory cytokines such as IL-2 [88] and nominal antigens [89, 90], and (3) result in extensive, apoptotic death of the T cells within the DC-T cell clusters [89, 91].