Emerging Frontiers in Zebrafish Embryo Cell Lines: From Protocols to Biomedical Applications

Zebrafish (Danio rerio) has become a pivotal vertebrate model in biomedical research, renowned for its genetic similarity to humans, optical transparency, rapid embryonic development, and amenability to experimental manipulation. In recent years, the derivation of cell lines from zebrafish embryos has unlocked new possibilities for in vitro studies across developmental biology, toxicology, disease modeling, and genetic engineering. These embryo-derived cultures offer scalable, reproducible, and ethically favorable alternatives to in vivo approaches, enabling high-throughput screening and mechanistic exploration under defined conditions. This review provides a comprehensive overview of protocols for establishing and maintaining zebrafish embryonic cell lines, emphasizing culture conditions, pluripotency features, transfection strategies, and recent innovations such as genotype-defined mutant lines generated via CRISPR/Cas9 and feeder-free systems. We also highlight emerging applications in oncology, regenerative medicine, and functional genomics, positioning zebrafish cell lines as versatile platforms bridging animal models and next-generation in vitro systems. Their ongoing optimization holds promise for improved reproducibility, reduced animal use, and expanded translational impact in biomedical research.