Development and characterization of five novel cell lines from snubnose pompano, Trachinotus blochii (Lacepede, 1801), and their application in gene expression and virological studies.

Five novel permanent cell lines have been established from gill, heart, kidney, eye and fin of snubnose pompano, Trachinotus blochii. They were designated as snubnose pompano gill (SPG), snubnose pompano heart (SPH), snubnose pompano kidney (SPK), snubnose pompano eye (SPE) and snubnose pompano fin (SPF), respectively. All these cell lines were characterized and cryopreserved successfully at different passage levels. Cell lines were passaged every alternate day; SPG, SPH, SPK, SPE and SPF cell lines attained passage levels of 68, 74, 82, 79 and 106, respectively, since the initiation of their development in 2019. The cell lines grew well in Leibovitz's 15 medium containing 15% foetal bovine serum at 28°C. Immunophenotyping of the cell lines revealed the presence of fibronectin and pancytokeratin. No mycoplasma contamination was found. The transfection study revealed the gene expression efficiency of these cell lines by expressing the green fluorescent protein (GFP). The authentication on origin of cell lines from T. blochii was confirmed by amplification of species-specific mitochondrial cytochrome oxidase I gene. The results showed the susceptibility of these cell lines to fish nodavirus (FNV) and tilapia lake virus (TiLV) and resistance to cyprinid herpesvirus 2 (CyHV-2). The FNV infection in the cell lines was confirmed by RT-PCR, Western blot, ELISA and immunocytochemistry, while TiLV infection was confirmed by RT-PCR assay. These results revealed that these cell lines are suitable for virological and foreign gene expression studies.

Zebrafish fin-derived fibroblast cell line: A model for in vitro wound healing.

The goal of this study was to develop and characterize a cell line from the caudal fin tissue of zebrafish and also its application as an in vitro model to study the effect of H2 O2 in wound healing. Fibroblastic cell line was developed using explant culture method from caudal fin tissue of zebrafish and characterized. This cell line was named as DrF cell line. The DrF cells treated with 0-10 µM/ml H2 O2 were tested for viability, proliferation and motility by MTT assay, trypan blue assay and chemotaxis assay, respectively. Among the different concentrations of H2 O2 , 4 µM was found to be nontoxic to study cell migration in in vitro scratch wound assay. Furthermore, the expression of proliferating cell nuclear antigen (PCNA) and chemokine receptor (CXCR4) genes was carried by qPCR. The cell survival, proliferation and migration were extremely enriched at 4 µM level of H2 O2 . We observed accelerated wound closure in DrF cells treated with H2 O2. The qPCR results indicated that H2 O2 markedly up-regulated mRNA expression of PCNA and CXCR4. The findings from our study suggest that H2 O2 at low levels promotes cell survival, proliferation, migration and wound healing in DrF cells.