Herpes is a sexually transmitted infection (STI) caused by herpes simplex virus (HSV). Herpes is a very common infection that can persist in your body for life. This infection causes small, painful, fluid-filled blisters to reappear on the skin, mouth, lips (cold sores), eyes, or genitals. More than half of Americans have oral herpes, and about one sixth have genital herpes.
Virus Classification of HSV
There are two types of herpes simplex virus: HSV-1 and HSV-2, also known as Human alphaherpesvirus 1 and Human alphaherpesvirus 2. They are two members of the human Herpesviridae family, a group of new viruses that produce viral infections in the majority of humans.
HSV-1 is mainly transmitted through oral contact to cause infection in or around the mouth (oral herpes). HSV-2 is transmitted almost exclusively through genital contact during sexual intercourse, resulting in genital or anal area (genital herpes) infection. However, the location of lesions does not necessarily indicate the type of virus, because in some unique subsets, HSV-1 is more associated with genital infection than HSV-2. These two infections are mostly asymptomatic or undetected, but can cause painful blisters or ulcers at the site of infection, ranging from mild to severe.
Fig.1 Herpes infection by HSV-1.
Structure of HSV
The structure of HSV is composed of a relatively large, double stranded, linear DNA genome, which can reach 240 kbp. The viral DNA is packaged in a complex T = 16 icosahedral capsid, which is embedded in a proteinaceous layer known as the tegument that is surrounded by a host-derived lipid envelope. The envelope of the virus is covered with glycoproteins that regulate the attachment and entry of the virus. By fusing its envelope with the plasma membrane of the host cell, HSV virions enter the host cell, making the nucleocapsid and tegument enter the cytoplasm. The nucleocapsid is transported along the microtubule to the center of microtubule tissue, and then from there to the nucleus. Then the nucleocapsid combines with the nuclear pore complex, and its genome is injected into the nucleus through the nuclear pore complex.
Fig.2 Structure and genome of HSV. (Argnani, 2005)
Genome of HSV
The genome of HSV is very complex, including two unique regions, namely long unique region (UL) and short unique region (US), as well as the terminal reverse repeat sequence found at both ends of HSV, called repeat long sequence (RL) and repeat short sequence (RS). Of the 74 known open reading frames (ORFs), UL contains 56 viral genes, while US contains only 12.
The following table lists some popular targets in HSV antibody design and their functions.
| ORF | Function |
|---|---|
| ICP0 | E3 ubiquitin ligase that activates viral gene transcription by opposing chromatinization of the viral genome and counteracts intrinsic- and interferon-based antiviral responses. |
| UL27 | Glycoprotein B, Surface and membrane |
| UL29 | Major DNA-binding protein |
| US6 | Glycoprotein D, Surface and membrane |
| UL44 | Glycoprotein C, Surface and membrane |
| US3 | Serine/threonine-protein kinase |
| US8 | Glycoprotein E, Surface and membrane |
| UL54 | Transcriptional regulation and inhibition of the STING signalsome |
| RS1 | Major transcriptional activator. Essential for progression beyond the immediate-early phase of infection. IEG transcription repressor. |
| UL1 | Viral replication |
| UL42 | DNA polymerase processivity factor |
What Creative Biolabs offers?
In order to better understand the antigen structure of HSV and the basis of protective immunity, Creative Biolabs provides a large number of anti-HSV antibodies for hot targets to meet the needs of customers. For special HSV antibodies, our expert team has the ability to provide comprehensive services for specific project needs, including ViroAntibody discovery, ViroAntibody engineering, ViroAntibody customized and ViroAntibody neutralization assays services. If you are interested in our anti-HSV antibody products or services, please feel free to contact us for more details.
Reference
- Argnani, R., et al. “Replication-competent herpes simplex vectors: design and applications.” Gene. Ther. 12 (2005): 170-177.
