Repeated aminoglycoside exposure activates interferon-stimulated genes in human renal proximal tubular models.

Aminoglycosides remain clinically important antibiotics, but their use is limited by nephrotoxicity. Although proximal tubular accumulation mediated by megalin is well established, the downstream cellular response is still incompletely understood. Here, we compared repeated-dose transcriptomic responses to gentamicin and tobramycin in a panel of human proximal tubular models comprising primary proximal tubular epithelial cells (PTEC; three donors), human iPSC-derived proximal tubular-like cells (PTL; three donors), RPTEC/TERT1 cells, and HK-2 cells. Cells were exposed daily for seven days to 12, 250, or 450 µg/mL gentamicin or tobramycin, and gene expression was assessed using the TempO-Seq EU-ToxRisk v2.1 panel followed by DESeq2 analysis. Primary PTEC and PTL showed the clearest and most coherent response, characterised by strong induction of interferon-stimulated genes including IFI27, IFI6, IFIT1-3, ISG15, MX1, OAS1, UBE2L6, USP18, IFI44L, HERC6, and RSAD2. Targeted regulator analysis showed strong enrichment of overlapping ISGF3, IRF7, and IRF1 target networks, consistent with a dominant interferon-stimulated gene program, together with a smaller NF-κB-associated inflammatory branch. In contrast, RPTEC/TERT1 and HK-2 cells showed weaker and less coherent responses. Tobramycin generally induced a stronger and more consistent transcriptional response than gentamicin across responsive models. These data identify a robust innate immune-like transcriptional signature in human proximal tubular models following repeated aminoglycoside exposure and support primary PTEC and PTL as more informative in vitro systems for mechanistic investigation of aminoglycoside nephrotoxicity.