To account for the greater mortality of FV3-infected frogs that had been enriched for CSF-1-MΦs and reconcile the greater FV3 loads in these animals, we next performed histological analyses of kidneys from r-ctrl-, rCSF-1- and rIL-34-injected and FV3 infected frogs after 3, 7 and 21 days of infection (Figure 3). This evidence concerns the gene CSF1 and infection.