Establishment of an in vitro model from the vulnerable fish species Coregonus maraena (maraena whitefish): Optimization of growth conditions and characterization of the cell line

Abstract

In this study, a cell line of the fish species Coregonus maraena was produced for the first time. C. maraena is an endangered species, and studies indicate that this fish species will be affected by further population declines due to climate change. This cell line, designated CMAfin1, has been maintained in Leibovitz L‐15 supplemented with 10% fetal bovine serum over 3 years. Both subculturing and storage (short‐term storage at −80°C and long‐term storage in liquid nitrogen) was successful. Cell morphology and growth rate were consistent from passage 10 onwards. Immunocytochemical examination of cellular proteins and matrix components confirmed the mechanical stability of the cells. Actin, fibronectin, vinculin, vimentin, and tubulin are present in the cells and form a network. In addition, the transport of molecules is ensured by the necessary proteins. Gene expression analysis showed a shift in the expressions of stem cell markers between younger and higher passages. While SOX2 and IGF1 were more highly expressed in the seventh passage, SOX9 and IGF2 expressions were significantly increased in higher passages. Therefore, the stable cell culture CMAfin1 can be used for applied analysis to further understand the cell physiology of C. maranea.

Status assessment and opportunities for improving fish welfare in animal experimental research according to the 3R-Guidelines

“…In addition, cell lines should also be established for the fish species of the temperate climate zone, because numerous in vivo experiments are being carried out in "climate research" in particular. Thereby, the production of cell lines from IUCN red-listed fish species should be a priority in order to avoid further reducing these populations through animal testing (Kaya et al 2022). In the last decades, it has been shown that climate change and the associated rising temperatures have a significant impact on fish (e.g.…”