Autophagy in Virus Infection: A Race between Host Immune Response and Viral Antagonism

Abstract

Virus-infected cells trigger a robust innate immune response and facilitate virus replication. Here, we review the role of autophagy in virus infection, focusing on both pro-viral and anti-viral host responses using a select group of viruses. Autophagy is a cellular degradation pathway operated at the basal level to maintain homeostasis and is induced by external stimuli for specific functions. The degradative function of autophagy is considered a cellular anti-viral immune response. However, autophagy is a double-edged sword in viral infection; viruses often benefit from it, and the infected cells can also use it to inhibit viral replication. In addition to viral regulation, autophagy pathway proteins also function in autophagy-independent manners to regulate immune responses. Since viruses have co-evolved with hosts, they have developed ways to evade the anti-viral autophagic responses of the cells. Some of these mechanisms are also covered in our review. Lastly, we conclude with the thought that autophagy can be targeted for therapeutic interventions against viral diseases.

Blue light irradiation exerts anti-viral and anti-inflammatory properties against herpes simplex virus type 1 infection

“…Autophagy is a catabolic process to maintain cellular function in host cells upon stimulation by viruses and other pathogens, although the role of autophagy is controversial as a double-edged sword during infection [ 40 ]. Functional autophagic responses can be beneficial for regulating viral replication, but they also act as host factors for inhibiting viral distribution by degrading viral proteins [ 41 , 42 ]. It is also evident that ICP34.5 polypeptide encoded by HSV-1 restricts host beclin-1, which is an autophagic marker that inhibits autophagy and supports viral replication.…”

Autophagy of the ER: the secretome finds the lysosome

“…A few viruses, however, appear to use ER-phagy receptors to promote infection. In some cases, these viruses co-opt the ER-phagy receptors for their morphogenic functions; in others, the virus may have evolved to hijack autophagy itself as part of productive infection [58,59]. To illustrate the complex interplay between ERphagy and viral infection, we focus here on advances in flavivirus research, as well as a few studies of filovirus, picornavirus, and most recently, coronavirus.…”

Interplay between Autophagy and Herpes Simplex Virus Type 1: ICP34.5, One of the Main Actors

“…Macroautophagy is broadly considered an innate immune response that protect cells from viral infections [ 109 ]. Due to the antiviral role of autophagy, pharmacological modulation of this pathway has been proposed as a potential tool to fight HSV-1 infection [ 110 ].…”