Current status and future prospects in the search for protein biomarkers of immunosenescence.

Complex adaptations including changes in cellular redox status, the production of high levels of pro-inflammatory cytokines and alterations in immunity occur as the result of aging of the immune system (immunosenescence). These events are thought to underlie the progression of chronic degenerative diseases of aging, such as atherosclerosis, Type 2 diabetes and Alzheimer's disease. It is envisaged that identifying early biomarkers of immune aging would aid in identifying individuals at risk of age-related disease and would allow the discovery of novel intervention strategies. Proteomics has emerged as a rapidly expanding and innovative field, investigating protein expression, interaction and function at a global level. Several proteomic strategies, including use of mass spectrometry and non-mass spectrometry-based detection systems (including secondary antibody labeling with fluorescent tags) may be particularly advantageous in identifying biomarkers of immune health. Application of these approaches may identify factors that both contribute to (and define) age-dependent deregulation of the immune system.