An alternative perspective on the challenges facing science today
Update: An edited version of this article has been published by Antibody Genie. Thanks to Dr. Colm Ryan for the invitation. Check out the article here: www.antibodygenie.com/blog/can-infection-cause-chronic-disease/
With non-communicable diseases (or NCDs, which include heart disease, diabetes, cancer) now responsible for the most deaths worldwide, large investments into research on these diseases are helping us understand their causes. Many of these diseases have something in common, they involve chronic inflammation. Cells normally triggered by the immune system to fight infection, are persistently activated by factors produced within the body (endogenous factors), eventually causing damage to bodily tissues and beginning the disease processes involved in the development of diabetes, cancer and atherosclerosis - the build-up of fatty plaques in the arteries causing heart attacks and strokes. This begs the question, if both infection and endogenous factors can trigger the same immune responses that are known to cause NCDs, could infection directly cause NCDs?
Triggering our immune defences A good example of the responses triggered by both infection and endogenous factors starts with the well-characterised family of Toll-like receptors (TLRs), which are found on the surface of many immune cells. These receptors play a key role in innate immunity – the first line of defence against infection. Each of the 9 members of the TLR family recognise different components of pathogens, for example TLR4 recognises lipopolysaccharide (LPS) found on the outer membrane of certain types of bacteria, and TLRs 3 and 7 recognise viral ribonucleic acids or RNAs, which viruses release into the host cell they infect to exploit the cell’s machinery to produce its damaging viral proteins. When TLRs bind to a molecule they recognise, they can activate a sequence of proteins ending with a protein called NFkB (NFkappaB) and/or the Interferon regulatory factor (IRF) family, which are responsible for the production of numerous inflammatory proteins [1]. Once an immune response is triggered following TLR activation, it is usually sufficient to successfully destroy the infection. Thus, the infection is short-lived and the immune system can return to a resting state. |
AuthorDr. Anusha Seneviratne This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Categories
All
Archives
March 2020
|