As total DC numbers in the Ccr2-/- mice were not significantly different than those observed in B6 mice at 24 hours post-infection, but were significantly different at 48 hours post-infection, it is likely that monocytes are the major producers of TNF and IL-12 at 24 hours post-infection, with an additional contribution from DCs occurring at later timepoints. The gene discussed is CCR2; the disease is infection.