Submitted to: International Symposium of Animal Functional Genomics
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/2008
Publication Date: 4/7/2008
Citation: Miller, L., Harhay, G., Lager, K., Kehrli Jr., M., Laegreid, W., Neill, J. 2008. In depth global analysis of gene expression levels in porcine alveolar macrophages following infection with porcine reproductive and respiratory syndrome virus [abstract]. ARK-Genomics Conference 2008: 3rd International Symposium on Animal Functional Genomics. Paper No. ISAFG-P22. p. 38. Interpretive Summary:
Technical Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen of swine worldwide. Infection of the preferential target cells, porcine alveolar macrophages (PAMs), by PRRSV causes significant changes in their function by mechanisms that are not understood. Serial Analysis of Gene Expression (SAGE) libraries were constructed from in vitro mock-infected and PRRSV strain VR-2332-infected PAMs at 0, 6, 12, 16 and 24 hours post-infection. Each SAGE library was sequenced to obtain >95,000 tags per time point. The sequences were processed to account for sequencing error before generating tag:count databases of relative abundance. Tags were mapped to transcripts and genes by exact regular expression matching to sequences in available databases. More than 590 unique tags with significantly altered expression levels were identified (p<0.01 with Bonferroni correction). Validity and kinetics of expression of SAGE identified genes were confirmed using real-time RT-PCR. Expression of the identified innate immune response genes (including both cytokine and chemokine encoding transcripts known to be altered by other pathogens) showed no or very little change post-infection. Expression of arginase showed a significant, short-lived increase in expression at 6 hours post-infection indicating possible inhibition or lack of a pro-inflammatory response by inhibition of inducible nitric oxide synthase (iNOS) activity. This study represents the first comprehensive evaluation of gene expression in PRRSV-infected PAM, including identification of potential proteins and pathways that may be utilized for the control of PRRSV infection.