Cultured corneas show dendritic spread and restrict herpes simplex virus infection that is not observed with cultured corneal cells

Abstract

Herpes simplex virus-1 (HSV-1) causes life-long morbidities in humans. While fever blisters are more common, occasionally the cornea is infected resulting in vision loss. A very intriguing aspect of HSV-1 corneal infection is that the virus spread is normally restricted to only a small fraction of cells on the corneal surface that connect with each other in a dendritic fashion. Here, to develop a comprehensive understanding of the susceptibility of human corneal epithelial (HCE) cells to HSV-1 infection, we infected HCE cells at three different dosages of HSV-1 and measured the outcomes in terms of viral entry, gene and protein expression, viral replication and cytokine induction. In cultured cells, infectivity and cytokine induction were observed even at the minimum viral dosage tested, while a more pronounced dose-restricted infectivity was seen in ex vivo cultures of porcine corneas. Use of fluorescent HSV-1 virions demonstrated a pattern of viral spread ex vivo that mimics clinical findings. We conclude that HCE cell cultures are highly susceptible to infection whereas the cultured corneas demonstrate a higher ability to restrict the infection even in the absence of systemic immune system. The restriction is helped in part by local interferon response and the unique cellular architecture of the cornea.

An off-target effect of BX795 blocks herpes simplex virus type 1 infection of the eye

“…6, G and H). In parallel, we also used a porcine cornea culture model to determine the antiviral activity of BX795 (42)(43)(44). Consistent with our findings, BX795 treatment blocked HSV-1 infection in porcine corneas, as seen from representative immunofluorescence images ( fig.…”

Emerging Roles of Heparanase in Viral Pathogenesis

“…HSV-1 can cause mucocutaneous, ocular and systemic illnesses. The virion belongs to the Alphaherpesviridae sub-family of herpesviruses, comprising of a lipid coat, a nucleocapsid, tegument proteins, and a double-stranded DNA genome [ 30 , 31 ]. During entry, the HSV-1 virion binds to the cell surface HS via the viral envelope glycoproteins gB and gC, and use this interaction to slide down membrane projections such as filopodia to reach the cell body for membrane penetration [ 32 ].…”

New Paradigms for the Study of Ocular Alphaherpesvirus Infections: Insights into the Use of Non-Traditional Host Model Systems

“…Corneas may or may not be scarified prior to infection with herpesvirus and are either covered with media and cultured for up to 8 days, or placed in a rocking air-liquid interface and cultured for up to three weeks. Thus far, corneoscleral explants have been described to model HSV-1 infection using human, rabbit and pig corneas [ 103 , 104 , 105 , 106 ], CHV-1 infection using canine corneas [ 8 ] and FHV-1 infection using feline corneas [ 72 , 107 ]. The infection in these cornea models was shown to be similar across the different viruses and is depicted schematically in Figure 2 .…”

“…The explants are typically infected at a high multiplicity of infection (MOI) to ensure infection and, as a result, virus is found uniformly across the epithelium, resulting in damage to the entire epithelium. However, using a porcine cornea explant to model HSV-1 growth, Thakkar et al showed that dendritic ulcerations form in a virus inoculum-dependent manner, eventually leading to the formation of larger, geographic ulceration commonly observed in vivo [ 106 ]. Additionally, some models suggest that cells deeper in the corneal tissue, including endothelial cells and other unidentified cells, may also become infected [ 8 , 105 ] ( Figure 2 ).…”