Transcriptome Differences in Porcine Alveolar Macrophages from Tongcheng and Large White Pigs in Response to Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Infection.

Wan Liang,Bang Liu,Yueran Zhen,Likai Ji,Qingde Zhang,Yu Zhang,Xuewen Xu

doi:10.3390/ijms18071475

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) is a single-stranded positive-sense RNA virus that can cause devastating reproductive failure and respiratory tract lesions, which has led to serious damage to the swine industry worldwide. Our previous studies have indicated that Tongcheng (TC) pigs, a Chinese local breed, have stronger resistance or tolerance to PRRSV infection than Large White (LW) pigs. This study aims to investigate their host transcriptome differences in porcine alveolar macrophages (PAMs) at 7 days post challenge. Transcriptome profiling of PAMs from PRRSV infected and control pigs of these two breeds were performed using RNA-sequencing. For both breeds, there were 1257 common differentially expressed genes (DEGs) in response to PRRSV infection, involving hepatic fibrosis/hepatic stellate cell activation, phospholipase C, and granulocyte adhesion and diapedesis pathways. For TC pig, 549 specific DEGs were identified, including VAV2, BCL2 and BAX, which were enriched in activation of leukocyte extravasation and suppression of apoptosis. While, 898 specific DEGs were identified in LW pigs, including GNAQ, GNB5, GNG2, CALM4 and RHOQ, which were involved in suppression of Gαq and PI3K-AKT signaling. This study provides an insight into the transcriptomic comparison of resistant and susceptible pigs to PRRSV infection. TC pigs may promote the extravasation and migration of leukocytes to defend against PRRSV infections and suppress apoptosis of the infected macrophages to increase antigen presentation, thereby reducing the lung lesions.

Highlights

As one of the most devastating diseases in the swine industry, porcine reproductive and respiratory syndrome (PRRS) has aroused much concern worldwide since its emergence
The disease is characterized by reproductive failure and severe respiratory symptoms and the causative agent is the porcine reproductive and respiratory syndrome virus (PRRSV), an enveloped, single-stranded positive-sense RNA virus, which belongs to the Arteriviridae family [1]
Only three individuals from each group were used, it still provides insights into a general trend and offers valuable data for differentially expressed genes (DEGs) and pathway analyses related to PRRSV infection and resistance

Summary

Introduction

As one of the most devastating diseases in the swine industry, porcine reproductive and respiratory syndrome (PRRS) has aroused much concern worldwide since its emergence. The disease is characterized by reproductive failure and severe respiratory symptoms and the causative agent is the porcine reproductive and respiratory syndrome virus (PRRSV), an enveloped, single-stranded positive-sense RNA virus, which belongs to the Arteriviridae family [1]. Once the host is infected by PRRSV, they will enter an acute viraemic stage, which lasts from one to four weeks, followed by a virus clearance stage with variable lengths of time, ranging from several weeks to 200 days [1,3,4]. As a positive-sense RNA virus, PRRSV evolves extremely rapidly and is divided into two main serotypes, North American and European, which display diverse pathogenic characteristics and host immune responses [5,6]. Due to the immune evasion and highly variable character of PRRSV, the development of commercial vaccines has so far been ineffective. Other alternative strategies, such as breeding with highly resistant pigs, have been explored as a potential way to combat PRRS outbreak [7,8]

Objectives

Methods

Results

Discussion

Conclusion