CXCR1 and infection: Because we observed extensive leukocyte infiltration into the kidneys of CSF-1-MΦ-enriched, FV3-infected frogs at later infection times (Figure 3), we next examined the kidneys of r-ctrl, rCSF-1- and rIL-34-administered animals after 28 dpi for expression of a panel of CC and CXC chemokine genes (Figure 4A,B).