Establishment and evaluation of an immortalized dzo kidney cell line

Immortalized cell lines constructed through transfecting genes such as the hTERT and the SV40-LT provide stable cellular resources for both scientific exploration and industrial implementation. Although advancements have been documented in the establishment of immortalized cell types, research on immortalization of specialized animal cell types remains an underexplored domain. To explore the applicable value of the dzo, a yak-cattle hybrid endemic to northwestern China, and develop potential cell substrates that can be used for the production of BVDV vaccines, this study adopts an immortalization strategy with the hTERT and SV40-LT genes to construct an immortalized dzo kidney cell line. This study employed a lentiviral vector system to stably integrate SV40-LT into dzo renal cells, successfully generating the immortalized NBLS cell line. Compared to liposome-mediated transfection, lentiviral delivery demonstrated superior gene transfer efficiency through high integration capacity and broad tropism. NBLS cells maintained robust proliferation (viability > 90%), normal cell cycle distribution, and diploid karyotype (2n = 60) through 50 passages, whereas hTERT-only transfectants exhibited viability decline below 70% after passage 10. Functional validation revealed NBLS cells displayed enhanced BVDV susceptibility (lgTCID50 = 10^- 6.59/0.1 mL), with tenfold increased sensitivity compared to primary counterparts. The results will provide potential materials for BVDV vaccine production and species-specific cellular models for investigating plateau-adapted disease resistance mechanisms and screening novel vaccine antigens.