PAMs combined with Marc-145 cells for isolation of porcine reproductive and respiratory syndrome virus and genetic evolution analysis
Sun Kehui
Wang Liling
Tao Song
Chen Borong
Li Yue
Li Ming
Abstract：The study aimed to isolate porcine reproductive and respiratory syndrome virus(PRRSV)using the combination of porcine alveolar macrophages(PAMs)and Marc-145 cells,and to conduct genetic evolution analysis on the isolated virus.Three lung samples from a suspected PRRSV-positive pig herd in a certain area of Yunnan were collected.The processing solution was first inoculated onto PAMs,and when the cells showed obvious lesions,it was transferred to Marc-145 cells for virus isolation and culture.The ORF7 identification primer was used to confirm the isolation results,and RT-PCR was used to amplify the ORF5 gene for genetic evolution analysis.The results showed that a PRRSV with a titer of 10-6.57 TCID50/mL was isolated in this study,and it was named XW2025.The isolate was passaged in Marc-145 cells,causing stable lesions in the cells.The ORF7 identification primer could amplify a 432 bp target band;The nucleotide homology analysis of the ORF5 gene showed that the isolate XW2025 was 93.4%similar to the representative strain NADC30 of the American lineage,and the phylogenetic tree showed that it was in the same branch as the reference strain DANC30.The study demonstrated that a highly pathogenic PRRSV was successfully isolated in this experiment.
Keywords：Porcine reproductive and respiratory syndrome virusGenetic evolutionVirus isolation
Publication Date：2026-02-15
Online Publishing Date：2026-03-16(First online date of this platform, not the publication date of the document)
Pages：5( 26-30 )