Lumpy Skin Disease Virus Infection Activates Autophagy and Endoplasmic Reticulum Stress-Related Cell Apoptosis in Primary Bovine Embryonic Fibroblast Cells

Abstract

Poxviruses have been associated with humans for centuries. From smallpox to mpox to lumpy skin disease virus (LSDV), members of the poxvirus family have continued to threaten the lives of humans and domestic animals. A complete understanding of poxvirus-mediated cellular processes will aid in the response to challenges from the viruses. In this study, we demonstrate that LSDV infection results in an abnormal ultrastructure of the endoplasmic reticulum (ER) lumen in primary bovine embryonic fibroblast (BEF) cells, and we further show that an ER imbalance occurs in LSDV-infected BEF cells. Additionally, we believe that ER stress-related apoptosis plays a role in the late apoptosis of BEF cells infected with LSDV, primarily through the activation of the CCAAT/enhancer binding protein homologous protein (CHOP)-Caspase-12 signal. In addition to cell apoptosis, a further investigation showed that LSDV could also activate autophagy in BEF cells, providing additional insight into the exact causes of LSDV-induced BEF cell death. Our findings suggest that LSDV-induced BEF cell apoptosis and autophagy may provide new avenues for laboratory diagnosis of lumpy skin disease progression and exploration of BEF cell processes.

Mastering Death: The Roles of Viral Bcl-2 in dsDNA Viruses

“…Adenovirus infection, rather than disrupting autophagy, induces autophagy when the adenovirus Bcl-2 homolog, E1B19K, interacts with Beclin 1 [ 158 ]. Autophagosomes were directly observed when the captipoxvirus Lumpy Skin Disease Virus (LSDV) infected bovine embryonic fibroblasts, suggesting that autophagy is directly involved in mediating cell death [ 159 ]. While autophagy may be initiated to destroy viruses through lysosomal degradation (xenophagy) and destroy gene products (virophagy) or organelles (mitophagy) to prevent apoptosis as part of an innate immunity response, it appears that multiple different levels of interference are employed by dsDNA viruses [ 160 ].…”