This 2016 German review was of the memory characteristics of immune cells:
“Innate immune memory has likely evolved as an ancient mechanism to protect against pathogens. However, dysregulated processes of immunological imprinting mediated by trained innate immunity may also be detrimental under certain conditions.
Evidence is rapidly accumulating that innate immune cells can adopt a persistent pro-inflammatory phenotype after brief exposure to a variety of stimuli, a phenomenon that has been termed ‘trained innate immunity.’ The epigenome of myeloid (progenitor) cells is presumably modified for prolonged periods of time, which, in turn, could evoke a condition of continuous immune cell over-activation.”
The reviewers focused on the particular example of atherosclerosis, although other examples were discussed of epigenetic remodeling to acquire immune memory:
“In the last ten years, several novel non-traditional risk factors for atherosclerosis have been identified that are all associated with activation of the immune system. These include chronic inflammatory diseases such as:
- rheumatoid arthritis,
- gout,
- psoriatic arthritis, and
- ankylosing spondylitis,
as well as infections with bacteria or viruses.”
The reviewers also discussed diet, mainly of various diets’ negative effects. On the positive side, I was interested to see a study referenced that used a common dietary supplement:
“Pathway analysis of the promoters that were potentiated by β-glucan identified several innate immune and signaling pathways upregulated in trained cells that are responsible for the induction of trained immunity.”
Other research into the epigenetic remodeling of immune system memory includes:
- Chronic pain causes epigenetic changes in the brain and immune system
- Epigenetic regulation of natural killer cells
- Assessing epigenetic origins of allergies and asthma
http://www.sciencedirect.com/science/article/pii/S1044532316300185 “Long-term activation of the innate immune system in atherosclerosis”
