CXCL8 is associated with aflatoxin B1-triggered injury and caspase-3 activation in porcine kidney epithelial PK15 cells: integrated transcriptomics and CRISPR/Cas9 knockout.

Aflatoxin B1 (AFB1) is a prevalent food- and feed-borne mycotoxin, and growing evidence indicates that the renal epithelium is a vulnerable target. However, host determinants that modify epithelial susceptibility remain poorly defined. Here, we investigated AFB1-triggered injury in porcine kidney epithelial PK15 cells and examined the contribution of CXCL8. PK15 cells were exposed to AFB1 (0-32 μM) to define dose-dependent cytotoxicity, and sub-IC50 conditions (4 and 8 μM for 24 h) were used for mechanistic analyses; RNA sequencing at 4 μM for 24 h was used as an exploratory screen to prioritize candidate susceptibility factors. CXCL8 emerged as the most strongly induced transcript and was subsequently evaluated using CRISPR/Cas9-mediated knockout. CXCL8 deficiency attenuated AFB1-induced loss of viability, reduced Annexin V/PI-positive cells, and alleviated mitochondrial ultrastructural injury. In parallel, CXCL8 knockout decreased ROS accumulation, partially restored intracellular GSH and the BCL2/BAX transcriptional ratio, and reduced caspase-3 induction and cleavage. Collectively, these data support CXCL8 as an AFB1-inducible susceptibility factor associated with oxidative stress amplification and caspase-3 activation in PK15 cells, while indicating that the upstream regulatory axis and the precise downstream signaling route require further validation in physiologically relevant renal models.