porcine-corneal-tissue-explant-to-study-efficacy-herpes-simplex-virus

Porcine Corneal Tissue Explant to Study the Efficacy of Herpes Simplex Virus-1 Antivirals

Viruses and bacteria can cause a variety of ocular surface defects and degeneration such as wounds and ulcers through corneal infection. With a ...

University of Illinois at Chicago

Herpes simplex virus-1 (HSV-1) infection is known to cause skin blisters, keratitis as well as deadly cases of encephalitis in some situations. Only a few therapeutic modalities are available for this globally prevalent infection. Very recently, a small molecule BX795 was identified as an inhibitor of HSV-1 protein synthesis in an ocular model of infection. In order to demonstrate its broader antiviral benefits, this study was aimed at evaluating the antiviral efficacy, mode-of-action, and toxicity of BX795 against HSV-1 infection of three human cell lines: HeLa, HEK, and HCE. Several different assays, including cell survival analysis, imaging, plaque analysis, Immunoblotting, and qRT-PCR, were performed. In all cases, BX795 demonstrated low toxicity at therapeutic concentration and showed strong antiviral benefits. Quite interestingly, cell line-dependent differences in the mechanism of antiviral action and cytokine response to infection were seen upon BX795 treatment. Taken together, our results suggest that BX795 may exert its antiviral benefits via cell-line specific mechanisms.

BX795 demonstrates potent antiviral benefits against herpes simplex Virus-1 infection of human cell lines.

Herpes simplex virus type 2 (HSV-2) causes recurrent lesions in the anogenital area that may be transmitted through sexual encounters. Nucleoside analogs, such as acyclovir (ACV), are currently prescribed clinically to curb this infection. However, in some cases, reduced efficacy has been observed due to the emergence of resistance against these drugs. In our previous study, we reported the discovery of a novel anti-HSV-1 small molecule, BX795, which was originally used as an inhibitor of TANK-binding kinase 1 (TBK1). In this study, we report the antiviral efficacy of BX795 on HSV-2 infection in vaginal epithelial cells  at 10 μM and  at 50 μM. Additionally, through biochemical assays  and histopathology , we show the tolerability of BX795 in vaginal epithelial cells at concentrations as high as 80 μM. Our investigations also revealed that the mechanism of action of BX795 antiviral activity stems from the reduction of viral protein translation via inhibition of protein kinase B phosphorylation. Finally, using a murine model of vaginal infection, we show that topical therapy using 50 μM BX795 is well tolerated and efficacious in controlling HSV-2 replication.

 and  Activity, Tolerability, and Mechanism of Action of BX795 as an Antiviral against Herpes Simplex Virus 2 Genital Infection.

Herpes simplex virus (HSV) can infect a broad host range and cause mild to life threating infections in humans. The surface glycoproteins of HSV are evolutionarily conserved and show an extraordinary ability to bind more than one receptor on the host cell surface. Following attachment, the virus fuses its lipid envelope with the host cell membrane and releases its nucleocapsid along with tegument proteins into the cytosol. With the help of tegument proteins and host cell factors, the nucleocapsid is then docked into the nuclear pore. The viral double stranded DNA is then released into the host cell's nucleus. Released viral DNA either replicates rapidly (more commonly in non-neuronal cells) or stays latent inside the nucleus (in sensory neurons). The fusion of the viral envelope with host cell membrane is a key step. Blocking this step can prevent entry of HSV into the host cell and the subsequent interactions that ultimately lead to production of viral progeny and cell death or latency. In this review, we have discussed viral entry mechanisms including the pH-independent as well as pH-dependent endocytic entry, cell to cell spread of HSV and use of viral glycoproteins as an antiviral target.

Article	Year
BX795 demonstrates potent antiviral benefits against herpes simplex Virus-1 infection of human cell lines. Antiviral research\| PubMed ID: 32380150	2020
and Activity, Tolerability, and Mechanism of Action of BX795 as an Antiviral against Herpes Simplex Virus 2 Genital Infection. Antimicrobial agents and chemotherapy\| PubMed ID: 32601167	2020
Herpes Simplex Virus Cell Entry Mechanisms: An Update. Frontiers in cellular and infection microbiology\| PubMed ID: 33537244	2020

Ipsita Volety

Biography

JoVE Journal Publications

Other Publications