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

Development and characterization of red seabream (Pagrus major) muscle satellite cell lines for cultivated seafood: highlighting serum reduction and microcarrier expansion

Cellular aquaculture requires well-characterized marine cell lines for sustainable seafood production. This study developed muscle satellite cell lines from red seabream (Pagrus major) (PMMSC) to support cultured seafood production. Primary cells, isolated via collagenase digestion (2.61 × 105 cells/mL), were cultured in L- 15 medium under varying FBS levels (10-20%) and temperatures (20-28 °C). Optimal growth occurred at 24 °C with 10% FBS, forming dense monolayers by day 9. Differentiation into myotubes, induced with 2% horse serum, was confirmed by myogenic protein expression (Pax7, MYH, MyoD, MyoG, Desmin) over 12 d. PMMSC proliferation was evaluated under reduced-serum conditions supplemented with Spirulina platensis extract, an algae-derived alternative to fetal bovine serum. The algae extract improved cell proliferation, demonstrating its potential for sustainable seafood production. Additionally, 3D cell expansion using gelatin microcarriers in a bioreactor resulted in an 8.18-fold increase in cell count, showcasing its potential for scalable production. This research provides a valuable resource for the cellular aquaculture field by establishing a well-characterized red seabream muscle satellite cell line and demonstrating the potential of algae-based serum replacements.

Establishment and characterization of a kidney cell line from hybrid snakehead (male Channa argus × female Channa maculata) and its susceptibility to hybrid snakehead rhabdovirus (HSHRV)

Hybrid snakehead (male Channa argus × female Channa maculata) is an emerging fish breed with increasing production levels. However, infection with hybrid snakehead rhabdovirus (HSHRV) critically affects hybrid snakehead farming. In this study, a fish cell line called CAMK, derived from the kidneys of hybrid snakehead, was established and characterized. CAMK cells exhibited the maximum growth rate at 28 °C in Leibovitz's-15 medium supplemented with 10% fetal bovine serum(FBS). Karyotyping revealed diploid chromosomes in 54% of the cells at the 50th passage (2n = 66), and 16S rRNA sequencing validated that CAMK cells originated fromhybrid snakehead, and the detection of kidney-specific antibodies suggested that it originated from kidney. .The culture was free from mycoplasma contamination, and the green fluorescent protein gene was effectively transfected into CAMK cells, indicating their potential use for in vitro gene expression investigations. Furthermore, qRT-PCR and immunofluorescence analysis revealed that HSHRV could replicate in CAMK cells, indicating that the cells were susceptible to the virus. Transmission electron microscopy revealed that the viral particles had bullet-like morphology. The replication efficiency of HSHRV was 107.33 TCID50/mL. Altogether, we successfully established and characterized a kidney cell line susceptible to the virus. These findings provide a valuable reference for further genetic and virological studies.