ICP47 Protein

Definition

ICP47 is a protein encoded by the herpes simplex virus (HSV) that functions as a virulence factor by interfering with the host's immune response. It is a key component in the viral evasion of the host's cytotoxic T-cell response, a crucial part of the adaptive immune system.

5 Must Know Facts For Your Next Test

1. ICP47 is an immediate-early gene product of the herpes simplex virus, meaning it is one of the first viral proteins expressed during infection.
2. ICP47 binds to the host's transporter associated with antigen processing (TAP) protein, which normally transports viral peptides to the cell surface for presentation to cytotoxic T-cells.
3. By binding to TAP, ICP47 blocks the translocation of viral peptides, preventing their display on the cell surface and effectively hiding the infected cell from detection by cytotoxic T-cells.
4. The inhibition of TAP by ICP47 is a crucial immune evasion strategy employed by the herpes simplex virus to establish a persistent infection in the host.
5. ICP47 is considered a key virulence factor for the herpes simplex virus, as it significantly impairs the host's ability to mount an effective cytotoxic T-cell response against infected cells.

Review Questions

• Explain how the ICP47 protein contributes to the virulence of the herpes simplex virus.
  • The ICP47 protein is a key virulence factor of the herpes simplex virus that enhances the virus's ability to evade the host's immune response. ICP47 binds to the host's TAP protein, which normally transports viral peptides to the cell surface for presentation to cytotoxic T-cells. By blocking this process, ICP47 prevents the infected cells from being recognized and targeted by the host's adaptive immune system, allowing the virus to establish a persistent infection.
• Describe the role of ICP47 in the herpes simplex virus's evasion of the host's cytotoxic T-cell response.
  • ICP47 is a crucial component of the herpes simplex virus's immune evasion strategy. By binding to the host's TAP protein, ICP47 blocks the translocation of viral peptides to the cell surface, preventing their display to cytotoxic T-cells. This effectively hides the infected cells from detection by the host's adaptive immune response, allowing the virus to evade the cytotoxic T-cell-mediated clearance of infected cells and establish a persistent infection in the host.
• Analyze the significance of the ICP47 protein in the overall virulence and pathogenesis of the herpes simplex virus.
  • The ICP47 protein is a critical virulence factor for the herpes simplex virus, as it plays a central role in the virus's ability to evade the host's adaptive immune response. By inhibiting the presentation of viral peptides to cytotoxic T-cells, ICP47 allows the virus to effectively hide from the host's primary defense against intracellular pathogens. This immune evasion strategy is a key contributor to the herpes simplex virus's capacity to establish persistent infections, which can lead to recurrent outbreaks and significant health consequences for the infected host. The importance of ICP47 in the virus's pathogenesis highlights the need for a deeper understanding of this protein and its potential as a target for novel therapeutic interventions.

Related terms

Virulence Factors:

Virulence factors are molecules produced by pathogens that contribute to their ability to infect, colonize, and cause damage to the host.

Cytotoxic T-cells: Also known as CD8+ T-cells, these immune cells recognize and destroy host cells infected with viruses or other intracellular pathogens.

Adaptive Immune Response: The adaptive immune response is the second line of defense against pathogens, involving the activation of specialized cells like T-cells and B-cells to target specific threats.