A recent study in twins has found that infection with cytomegalovirus(CMV) significantly altered over half of all the 204 immune system parameters tested. The paper also suggests that exposure to environmental factors appears to be the dominant force in changing the immune system over time.
CMV chronically infects the majority of the population by old age and has been implicated for some time as a driver in the dysfunction of the immune system with aging(known as "immunosenescence.") Immune system dysfunction and possibly the chronic inflammation associated with it, may play a part in a broad range of age-associated disabilities and diseases, far beyond only reducing the ability to fight off infections.
See the following posts for some further information on CMV and aging, including simple methods to reduce the chance of becoming infected with CMV:
http://www.longecity...ytomegalovirus/
http://www.longecity...ction-on-aging/
http://www.longecity...o-cmv-exposure/
1. Cell. 2015 Jan 15;160(1-2):37-47. doi: 10.1016/j.cell.2014.12.020.
Variation in the human immune system is largely driven by non-heritable
influences.
Brodin P(1), Jojic V(2), Gao T(2), Bhattacharya S(3), Angel CJ(4), Furman D(4),
Shen-Orr S(5), Dekker CL(6), Swan GE(7), Butte AJ(8), Maecker HT(9), Davis
MM(10).
Author information:
(1)Science for Life Laboratory, Department of Medicine, Solna, Karolinska
Institutet, 17121 Solna, Sweden; Department of Microbiology and Immunology,
Stanford University School of Medicine, Stanford, CA 94304, USA; Institute of
Immunity, Transplantation and Infection, Stanford University School of Medicine,
Stanford, CA 94304, USA. (2)Department of Computer Science, University of North
Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. (3)Institute of Immunity,
Transplantation and Infection, Stanford University School of Medicine, Stanford,
CA 94304, USA. (4)Department of Microbiology and Immunology, Stanford University
School of Medicine, Stanford, CA 94304, USA; Institute of Immunity,
Transplantation and Infection, Stanford University School of Medicine, Stanford,
CA 94304, USA. (5)Department of Immunology, Faculty of Medicine, Technion, Haifa
31096, Israel. (6)Department of Pediatrics, Stanford University School of
Medicine, Stanford, CA 94304, USA. (7)Stanford Prevention Research Center,
Department of Medicine, Stanford University School of Medicine, Stanford, CA
94304, USA. (8)Department of Pediatrics, Stanford University School of Medicine,
Stanford, CA 94304, USA; Center for Pediatric Bioinformatics, Lucille Packard
Children's Hospital, Stanford University, Stanford, CA 94304, USA. (9)Institute
of Immunity, Transplantation and Infection, Stanford University School of
Medicine, Stanford, CA 94304, USA; Human Immune Monitoring Center, Stanford
University School of Medicine, Stanford, CA 94304, USA. (10)Department of
Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA
94304, USA; Institute of Immunity, Transplantation and Infection, Stanford
University School of Medicine, Stanford, CA 94304, USA; Howard Hughes Medical
Institute, Stanford University School of Medicine, Stanford, CA 94304, USA.
Electronic address: mmdavis@stanford.edu.
There is considerable heterogeneity in immunological parameters between
individuals, but its sources are largely unknown. To assess the relative
contribution of heritable versus non-heritable factors, we have performed a
systems-level analysis of 210 healthy twins between 8 and 82 years of age. We
measured 204 different parameters, including cell population frequencies,
cytokine responses, and serum proteins, and found that 77% of these are dominated
(>50% of variance) and 58% almost completely determined (>80% of variance) by
non-heritable influences. In addition, some of these parameters become more
variable with age, suggesting the cumulative influence of environmental exposure.
Similarly, the serological responses to seasonal influenza vaccination are also
determined largely by non-heritable factors, likely due to repeated exposure to
different strains. Lastly, in MZ twins discordant for cytomegalovirus infection,
more than half of all parameters are affected. These results highlight the
largely reactive and adaptive nature of the immune system in healthy individuals.
Copyright © 2015 Elsevier Inc. All rights reserved.
PMCID: PMC4302727 [Available on 2016/1/15]
PMID: 25594173 [PubMed - in process]
http://www.ncbi.nlm....pubmed/25594173
http://www.the-scien...ental-Immunity/
