To distinguish between these 2 possibilities, we showed, through the use of a Ccr2–/– mouse (which lack circulating Ly6C+ monocytes but are CARD9-intact; ref. 24), that these mice could not clear the fungus from their brains over the course of infection, supporting the premise that influx of Ly6C+ monocytes are protective for CNS candidiasis. The gene discussed is CCR2; the disease is candidiasis.