Bovine natural killer cells are infected by BVDV and the infection results in changes in phenotype and activation markers (P6128)

Abstract

Abstract Bovine viral diarrhea virus infection results in immunosuppression and persistence infection of fetuses. Understanding the interaction between BVDV and NK cells is important to understand the ability of the virus to establish its infection especially through placental barrier to generate persistently infected animals. In this study, we demonstrated that BVDV is able to infect bovine NK cells by detecting the presence of BVDV RNA level up to 24 hours post infection without any increase in RNA levels over time. We also confirmed that although BVDV viral RNA was present, there was neither infectious virus release at any time post infection nor decrease in cell viability due to infection. Using immunofluorescence staining of NK cells with a mAb specific for BVDV E2 protein, we demonstrated the presence of BVDV E2 proteins in NK cells. The effect of BVDV strains that differ in its virulence or biotype on NK activation marker CD25 and phenotype markers CD2, NKp46 and the granule protein granulysin was determined. Highly virulent BVDV strains significantly decreased surface expression of each of these markers with a slight increase in the total number of cells expressing the markers 24 hour post infection. On the other hand less virulent strains increased significantly the percent of expression but with a slight decrease in the number of cells expressing the markers.