Fig. 1: KIM1 is dramatically upregulated in a cisplatin-induced AKI model, aggravating inflammation and apoptosis in renal tubular epithelial cells.

a Structural scheme of KIM1 domains. Signal signal peptide, Mucin mucin-containing domain, TM transmembrane domain, CytD cytosolic domain. b mRNA levels of several AKI biomarkers in mouse kidneys at Day 3 after cisplatin (Cis) injury. n = 3 mice per group. c KIM1 protein level in mouse kidneys at Day 3 after cisplatin injury. LE/SE, long/short exposure. n = 2 mice per group, each experiment was repeated at least three times independently with similar results obtained. d Representative images of immunohistochemistry staining and quantitation of KIM1 in renal sections at Day 3 after cisplatin injury. Scale bar, 50 μm. n = 4 mice per group. e, f MTT assays to assess the effects of KIM1 overexpression (e) or knockout (f) in HK-2 cells with or without 24 h cisplatin stress. Vec, pRK-5′Flag; KIM1, pRK-5′Flag-KIM1; Cas9, lenti-CRISPR/Cas9; KIM1 KO, lenti-CRISPR/Cas9-based KIM1 knockout. CT, without cisplatin treatment. n = 4-5 biological samples per group, each experiment was repeated at least three times independently with similar results obtained. g, h qPCR of inflammatory factors with KIM1 overexpression (g) or knockout (h) in HK-2 cells with or without 24 h cisplatin stress. n = 3 biological samples per group, each experiment was repeated at least three times independently with similar results obtained. i, j Western blots of apoptotic molecules in KIM1 overexpression (i) or knockout (j) HK-2 cells with or without 24 h cisplatin stress. Each experiment was repeated at least three times independently with similar results obtained. k, l Representative flow cytometry results and quantitative data of KIM1 overexpression (k) or knockout (l) HK-2 cells with or without 24 h cisplatin stress analyzed by Annexin V-FITC and propidium iodide (PI) labeling. Quantitative data provided the average and standard deviation from three independent experiments (percentage of apoptotic cells was calculated by Annexin-V positive cells (Q2 + Q3)). Each experiment was repeated at least three times with representative results shown. m–p Representative images of TUNEL assay (m, n) and quantitative results (o, p) in KIM1 overexpression (m, o) or knockout (n, p) groups. n = 5 biological samples per group, each experiment was repeated at least three times independently with similar results obtained. Scale bar, 50 μm. Data shown as mean ± SD. Two-tailed unpaired Student’s t-test was used for two experimental groups and one-way ANOVA for multiple experimental groups without adjustment. ^*P < 0.05; ^**P < 0.01. Exact P values are provided in Source Data.