key term - EBNA-1

Definition

EBNA-1 (Epstein-Barr Nuclear Antigen 1) is a protein encoded by the Epstein-Barr virus (EBV) that plays a crucial role in the pathogenesis of autoimmune disorders. It is a DNA-binding protein that is essential for the maintenance and replication of the EBV genome in latently infected cells.

5 Must Know Facts For Your Next Test

1. EBNA-1 is essential for the episomal maintenance and replication of the EBV genome in latently infected cells, allowing the virus to persist in the host.
2. EBNA-1 has been implicated in the development of several autoimmune disorders, including systemic lupus erythematosus (SLE), rheumatoid arthritis, and multiple sclerosis.
3. The molecular mimicry between EBNA-1 and certain self-antigens can lead to the production of cross-reactive autoantibodies, triggering an autoimmune response.
4. EBNA-1 has been shown to induce the expression of pro-inflammatory cytokines and chemokines, contributing to the inflammatory response in autoimmune diseases.
5. The persistence of EBNA-1 in latently infected cells and its ability to modulate the host's immune response are thought to be key factors in the development of EBV-associated autoimmune disorders.

Review Questions

• Explain the role of EBNA-1 in the maintenance and replication of the Epstein-Barr virus genome.
  • EBNA-1 is a critical protein encoded by the Epstein-Barr virus (EBV) that is essential for the maintenance and replication of the viral genome in latently infected cells. It binds to the EBV origin of replication, allowing the virus to persist in the host's cells and replicate along with the host's chromosomes during cell division. This ensures that the EBV genome is passed on to daughter cells, enabling the virus to maintain a lifelong infection in the host.
• Describe how the molecular mimicry between EBNA-1 and self-antigens can contribute to the development of autoimmune disorders.
  • The molecular mimicry between EBNA-1 and certain self-antigens, such as those found in tissues affected by autoimmune diseases, can lead to the production of cross-reactive autoantibodies. These autoantibodies mistakenly target and attack the body's own tissues, triggering an autoimmune response. This phenomenon is thought to be a key mechanism by which EBNA-1 contributes to the development of autoimmune disorders, such as systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis.
• Analyze the potential role of EBNA-1 in modulating the host's immune response and its implications for the pathogenesis of EBV-associated autoimmune disorders.
  • EBNA-1 has been shown to induce the expression of pro-inflammatory cytokines and chemokines, which can contribute to the inflammatory response observed in autoimmune diseases. Additionally, the persistent presence of EBNA-1 in latently infected cells may enable the virus to modulate the host's immune response, potentially leading to the evasion of immune surveillance and the perpetuation of autoimmune processes. This ability of EBNA-1 to influence the host's immune system is a critical factor in the development and progression of EBV-associated autoimmune disorders, as it can promote the breakdown of self-tolerance and the sustained autoimmune response.

Related terms

Epstein-Barr Virus (EBV): A ubiquitous human herpesvirus that is the causative agent of infectious mononucleosis and is associated with several autoimmune and malignant diseases.

Molecular Mimicry:

A phenomenon where a foreign antigen shares structural similarities with self-antigens, leading to the activation of an autoimmune response.

Autoantibodies:

Antibodies produced by the body's immune system that mistakenly target and attack the body's own tissues or organs.