31st July 2023

Immunology

The human body has a variety of methods to defend itself against viral infection. These include anatomical and chemical barriers, such as mucus and stomach acid, and chemical mediators of the immune system. The latter can be broken down into intrinsic methods (i.e. interferons, apoptosis, autophagy), the innate immune responses (i.e. complement, cytokines, natural killer cells) and the adaptive immune response (i.e. T cells and B cells). The subject is vast and beyond the remit of this section to fully address.

Interferons (IFNs) are arguably the most important of these defences to know about. IFNs are a crucial part of our intrinsic defence system – they are produced by virus-infected cells and uninfected sentinel cells (e.g. dendritic cells, macrophages and natural killer cells) in response to triggers from viruses.

IFN-α and -β are produced rapidly in the early stages of viral infection, and their binding to receptors triggers the synthesis of multiple cell proteins. Their expression has dramatic physiological consequences, resulting in symptoms such as fever, rigors, malise and nausea, which are well recognised as viral phenomena.

In the reference section, a course providing an overview of viral immunology can be found as further reading.