Minor envelope proteins from GP2a to GP4 contribute to the spread pattern and yield of type 2 PRRSV in MARC-145 cells

Front Cell Infect Microbiol. 2024 Mar 25:14:1376725. doi: 10.3389/fcimb.2024.1376725. eCollection 2024.

Abstract

In China, porcine reproductive and respiratory syndrome virus (PRRSV) vaccines are widely used. These vaccines, which contain inactivated and live attenuated vaccines (LAVs), are produced by MARC-145 cells derived from the monkey kidney cell line. However, some PRRSV strains in MARC-145 cells have a low yield. Here, we used two type 2 PRRSV strains (CH-1R and HuN4) to identify the genes responsible for virus yield in MARC-145 cells. Our findings indicate that the two viruses have different spread patterns, which ultimately determine their yield. By replacing the viral envelope genes with a reverse genetics system, we discovered that the minor envelope proteins, from GP2a to GP4, play a crucial role in determining the spread pattern and yield of type 2 PRRSV in MARC-145 cells. The cell-free transmission pattern of type 2 PRRSV appears to be more efficient than the cell-to-cell transmission pattern. Overall, these findings suggest that GP2a to GP4 contributes to the spread pattern and yield of type 2 PRRSV.

Keywords: PRRSV; cell-free; cell-to-cell; spread pattern; yield.

MeSH terms

  • Animals
  • Cell Line
  • Guanidines*
  • Piperazines*
  • Porcine Reproductive and Respiratory Syndrome*
  • Porcine respiratory and reproductive syndrome virus* / genetics
  • Swine
  • Vaccines*

Substances

  • GP 4
  • Vaccines
  • Guanidines
  • Piperazines

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This research was supported by the China National Key R&D Program during the 14th Five-year Plan Period (Grant No. 2023YFD1801300).