# Advances in the immunosuppression of porcine reproductive and respiratory syndrome virus

## TL;DR

This review explores how PRRSV causes immunosuppression in pigs, hindering vaccine effectiveness and complicating disease control.

## Contribution

The paper provides a comprehensive review of PRRSV's immunosuppressive mechanisms to guide future vaccine strategies.

## Key findings

- PRRSV evades the immune system through antigen escape and delayed antibody production.
- The virus inhibits dendritic cell function and induces regulatory T cells, weakening immune responses.
- Understanding these mechanisms can improve vaccine development and disease control.

## Abstract

Porcine reproductive and respiratory syndrome (PRRS) is a highly infectious disease caused by the PRRS virus (PRRSV), its impact is second only to that of African swine fever (ASFV). Since the discovery of this disease, comprehensive studies have been conducted on its genome structure, protein function, pathogenicity, transmission route, and epidemiology as well as vaccines, prevention, and control. Despite the availability of numerous vaccines, complete immune protection in pigs is lacking. This limitation may be attributed to immune evasion, immunosuppression, or inherent characteristics of pigs. From the view of immunosuppression, the antigen escape, delayed neutralization antibody production, T cell immunity, antibody dependence enhancement, dendritic cell function inhibition, regulatory T cell induction and thymic destruction of PRRSV were discussed in this review to better understand PRRSV pathogenesis and inform vaccine development.