Establishment and characterization of an ovarian cell line from red seabream (Pagrus major) and its application in fish toxicology.

Fish cell lines serve as ideal in vitro models for investigating the toxicity of environmental pollutants in fish. In this study, a novel cell line (PmOVC) derived from the ovary of red seabream (Pagrus major) was successfully established. Using polystyrene microplastics (PS-MPs)-a typical environmental pollutant-as the test substance, the toxicity sensitivity of the PmOVC cell line was systematically assessed from the dimensions of particle size intake and cell activity. The results showed that the PmOVC cells exhibited robust growth in M199 medium supplemented with 15% FBS at 23°C and high exogenous gene transfection efficiency and showed high sensitivity to the toxic effects of microplastics. Specifically, the smaller the particle size of microplastics, the higher the internalization efficiency of cells, among which 100 nm PS-MPs could be completely endocytosed into the cytoplasm; the concentration of PS-MPs was significantly positively correlated with the apoptosis rate of cells (R2 ≥ 0.8). In summary, the established PmOVC cell line provides a critical in vitro tool for in-depth investigation of the toxicological responses and underlying mechanisms of fish to environmental pollutants.