To induce Csf1 deletion, Csf1ΔCD4 mice and Csf1fl/fl littermate controls were fed tamoxifen chow beginning one month prior to infection and continuing through the duration of each experiment; disruption of Csf1 expression in CD4+ T cells was confirmed by RT-qPCR after infection (Fig 4E). The gene discussed is CSF1; the disease is infection.