Immune evasion

Definition

Immune evasion refers to the various strategies employed by viruses to avoid detection and destruction by the host immune system. These tactics can significantly influence a virus's ability to spread, establish infection, and cause disease, highlighting the intricate arms race between viruses and their hosts.

5 Must Know Facts For Your Next Test

1. Viruses can employ multiple mechanisms for immune evasion, including altering their surface proteins, secreting proteins that inhibit immune responses, and hiding within host cells.
2. Certain viruses, like HIV, integrate into the host genome and can remain latent, evading immune surveillance until reactivation occurs.
3. Zoonotic viruses often have enhanced immune evasion strategies because they need to adapt quickly to new hosts with different immune systems.
4. Vaccination poses a challenge for viruses due to their ability to rapidly mutate and evolve, leading to new strains that can evade vaccine-induced immunity.
5. The effectiveness of antiviral therapies may be compromised by immune evasion strategies as viruses adapt to escape the effects of these treatments.

Review Questions

• How do immune evasion strategies contribute to the persistence and spread of animal viruses?
  • Immune evasion strategies allow animal viruses to avoid detection by the host's immune system, which is crucial for their survival and replication. By employing tactics such as antigenic variation or latency, these viruses can establish long-term infections without being eliminated. This persistence enables them to spread effectively within populations, leading to outbreaks and complicating control efforts.
• Discuss the implications of immune evasion on the development of vaccines for zoonotic viruses.
  • Immune evasion poses significant challenges in vaccine development for zoonotic viruses because these pathogens can rapidly mutate or exhibit antigenic variation. This means that a vaccine effective against one strain may not provide protection against another. Additionally, understanding the specific immune evasion mechanisms employed by these viruses is essential for designing vaccines that stimulate a robust and lasting immune response capable of addressing these challenges.
• Evaluate how mechanisms of viral evolution and adaptation relate to immune evasion in the context of viral oncogenesis.
  • Viral evolution and adaptation play a critical role in immune evasion, particularly in oncogenic viruses that manipulate host cellular pathways. For instance, these viruses may acquire mutations that enhance their ability to evade immune detection while simultaneously promoting cell proliferation. This dual strategy not only allows them to establish persistent infections but also increases their potential to induce oncogenesis by disrupting normal cellular regulatory mechanisms. As a result, understanding this relationship is vital for developing targeted therapies for cancers associated with viral infections.

Related terms

Antigenic variation: A process by which viruses alter their surface proteins to evade recognition by the immune system, allowing them to persist in the host.

Immunosuppression: The reduction of the immune response, which can be either a natural occurrence in some viral infections or induced therapeutically to control disease.

Latency:

A phase in certain viral infections where the virus remains dormant within host cells, avoiding immune detection while being capable of reactivation.