Heat Shock Protein 70 in Cold-Stressed Farm Animals: Implications for Viral Disease Seasonality

Abstract

The seasonal patterns of viral diseases in farm animals present significant challenges to global livestock productivity, with cold stress emerging as a potential modulator of host-pathogen interactions. This review synthesizes current knowledge on the expression dynamics of heat shock protein 70 (HSP70) in farm animals under cold-stress conditions and its potential roles as (1) a viral replication facilitator and (2) an immune response regulator. This review highlights cold-induced HSP70 overexpression in essential organs, as well as its effects on significant virus life cycles, such as porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome virus (PRRSV), and bovine viral diarrhea virus (BVDV), through processes like viral protein chaperoning, replication complex stabilization, and host defense modulation. By integrating insights from thermophysiology, virology, and immunology, we suggest that HSP70 serves as a crucial link between environmental stress and viral disease seasonality. We also discuss translational opportunities targeting HSP70 pathways to break the cycle of seasonal outbreaks, while addressing key knowledge gaps requiring further investigation. This article provides a framework for understanding climate-driven disease patterns and developing seasonally adjusted intervention strategies.

Keywords: PEDV; PRRSV; animal cold stress; heat shock protein 70; viral diseases seasonality.

Figure 1

Multifactorial drivers of viral disease seasonality in intensive animal production systems. This schematic illustrates the complex interplay of environmental drivers (temperature and humidity), host-related factors (animal behavior, physiological stress, and immune function), pathogen characteristics (viral stability and transmission routes), vector dynamics, and husbandry practices that collectively influence the seasonal patterns of viral diseases in animal husbandry. The central circle highlights the impact of cold-season climate hazards on livestock, emphasizing the role of immune compromise. Arrows indicate the direction of influence between factors.

Figure 2

Roles of HSP70 at various steps in the PEDV life cycle. This diagram depicts the PEDV life cycle within a host cell, highlighting the involvement of host HSP70 at different stages. Double-sided red arrows denote binding interactions between host HSP70 and the PEDV spike (S) or membrane (M) proteins. Single-sided red arrows indicate key steps mediated or facilitated by HSP70 activity, including viral entry, uncoating, mRNA synthesis, and translation. Cold-exposure-induced HSP70 upregulation is shown to influence these processes.