Sca1^-/- kidneys display increased injury after IRI.

(A) Histograms (mean+sd) comparing Kim-1 and Ngal mRNA levels in uninjured NL and Sca1^-/- kidneys. p = 0.0258 and 0.0227, respectively. (B) Western blot detection of Kim-1 protein in uninjured kidneys and in kidneys 7 days post-IRI from three NL and Sca1^-/- animals. Kim-1 was significantly induced kidneys in uninjured kidneys (upper panel) and in IRI kidneys at day 7 (lower panel) post IRI in Sca1^-/- mice vs. NL mice (p = 0.0183 and p = 0.010, respectively). (C) Histograms (mean+sd) showing qPCR measurement of Sca-1 expression in wild-type kidneys after IRI. Normal control animals: n = 6 (0h), 6 (24h), 4 (48h), 5 (72h), 5 (7d). Sca1^-/-: n = 6 (controls), 4 (24h), 3 (48h), 6 (72h), 7 (7d). (D) High power H&E stain of representative 6 μm sections from control (Cont.) and Sca1^-/- kidneys 7 days post IRI. Tubular casts (black arrows) and increased interstitial cellularity (yellow arrow) were frequently observed in Sca1^-/- kidneys. Kidney injury scores (mean+s.d.) 7 days post IRI were 3.0 and 2.75 for two controls and 4.5, 3.5 and 3.5 for three Sca1^-/- mice. Injury scores of zero were derived for kidneys from uninjured control and Sca1^-/- mice.