CCR1 and infection: The third important new question arises from our data that neutrophil accumulation was decreased but not entirely eliminated in Ccr1−/− kidneys late after infection (Figure 4), and from our competitive repopulation study, which showed that, despite the significant skewing toward Ccr1+/+ neutrophils, Ccr1−/− neutrophils also trafficked from the blood into the kidney at day 9 post-infection (Figure 8).