Sibling-Derived Cell Lines of Whole Larval Siberian Sturgeon as an In Vitro Model System for Studying Inter-Individual Differences Within the Same Genomic Heritage.

Sturgeons, once resilient enough to outlive dinosaurs, are now critically endangered. All 26 species of Acipenseriformes face extinction due to anthropogenic causes. Despite their ecological and economic significance, sturgeon research lacks essential tools such as larval cell lines; the Cellosaurus database lists only one larval cell line (AOXlar7y from Atlantic sturgeon). Larval stages are key to understand fish development, representing a transitional phase between embryonic and adult life that is highly sensitive to temperature shifts, oxygen depletion and pollution. Larval cell lines therefore provide potential in vitro models for studying development and stress responses in endangered species. This study focused on establishing and initially characterizing five novel larval cell lines from siblings of the Siberian sturgeon (Acipenser baerii). The lines proved viable for long-term culture, bio-banking and transfer, displaying different morphologies ranging from epithelial-like to fibroblast-like. Functional assays showed variable mitochondrial activity and extracellular acidification rates. A preliminary targeted gene expression analysis revealed similarity to whole larvae within early passages and in vitro adaptations for certain genes (gapdh, vim, col1a1, pcna). These sibling-derived cell lines hold potential as in vitro tools to deeper explore the biology of Siberian sturgeon larvae and support conservation-focused research.