Havenar-Daughten et al. have shown that in the absence of IFNAR on CD4+ T cells, the CD4+ T cells are still able to become activated and proliferate following infection with LCMV-Arm; however, similar to CD8+ T cells, IFN-Is are required for their survival during the antigen-driven proliferation stage [97]. The gene discussed is IFNAR1; the disease is infection.