Establishment and Biological characterization of a Large Yorkshire Pig fibroblast line

Aim: This study aimed to establish the fibroblast cell bank of the Large Yorkshire pig in the form of somatic cells, and to study its biological characteristics, to explore long-term conservation and sustainable use of this genetic resource. Material and methods: Ear marginal tissue of the Large Yorkshire pig was used to establish a fibroblast cell line by direct culture of explants and cryopreservation techniques, and the quality of the cell line was assessed. Results: Biological analyses showed that the cells were morphologically homogenous fibroblasts, and the estimated population doubling time (PDT) was 72 hours. The growth curve appeared as a typical "S" shape as the cell growth passed through a latent phase, a logarithmic phase and a plateau phase. Tests for bacteria, fungi, viruses and Mycoplasma were negative. Analysis of lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) isoenzymes ruled out cross-contamination between cell lines. Karyotyping and G-banding indicated a total chromosome number of 2n = 36; the proportion of diploid cells in the population was 91-96%. The transfection efficiencies of pEGFP-N3, pEYFP-N1 and pDsRed1-N1 were between 5.14 and 12.13%. Bioindicators of the cell bank met all the standards of the American Type Culture Collection (ATCC). Conclusion: This study not only shows the effective preservation of the Large Yorkshire pig germplasm at the cellular level, but also provides a valuable experimental resource for fields including cell biology, medicine, genomics, post-genomics, genetic engineering and embryo engineering.