Establishment of the first dermal fibroblast cell line derived from the Indo-Pacific Bottlenose Dolphin (Tursiops aduncus) and its response to pollutant exposure

The Indo-Pacific bottlenose dolphin (Tursiops aduncus), classified as a new species since 1998, is underexplored in ecotoxicology owing to ethical constraints and the lack of specific in vitro models. Herein, we established the first skin fibroblast cell line (TaSF) from an Indo-Pacific bottlenose dolphin stranded along the Pearl River Estuary, China. TaSF cells exhibited strong proliferation in early passages but ceased mitosis at passage 19, likely owing to reaching the Hayflick limit. Morphology and immunofluorescence tests confirmed the fibroblastic nature of these cells. Karyotyping revealed 21 pairs of autosomes and 1 pair of sex chromosomes (XY), consistent with many cetaceans. To facilitate long-term future studies, TaSF cells were immortalized with exogenous simian virus 40 T antigen, creating the TaSFT cell line. The cytotoxic effects of 27 contaminants, including 6 organotins (OTs), 10 per- and polyfluoroalkyl substances (PFASs), and 11 phthalates (PAEs), on TaSFT cells were evaluated after 24-h exposure. Among these chemicals, OTs exhibited the strongest cytotoxicity, and both OTs and PFASs showed structure-related toxicity. These findings confirm the feasibility of TaSFT cells as a novel tool for ecotoxicity research on the Indo-Pacific bottlenose dolphin and highlight the need for further investigation into the environmental contaminant pressures on this species.