C5AR1 and acute kidney injury: A number of preclinical studies indicate that genetic ablation or pharmacological inhibition of C5aR1 decreases markers of renal injury, immune cell infiltration, and fibrosis in renal IRI [29,75,79,80], unilateral uretal obstruction (UUO) models of obstructive nephropathy and fibrosis, uropathogenic Escherichia coli (UPEC)-induced pyelonephritis [81,82], and folic acid (FA)-induced AKI [73].