Repository logo
 

CMV immune evasion and manipulation of the immune system with aging

Published version
Peer-reviewed

Type

Article

Change log

Authors

Jackson, SE 
Redeker, A 
Arens, R 
van Baarle, D 
van den Berg, SPH 

Abstract

Human cytomegalovirus (HCMV) encodes numerous proteins and microRNAs that function to evade the immune response and allow the virus to replicate and disseminate in the face of a competent innate and acquired immune system. The establishment of a latent infection by CMV, which if completely quiescent at the level of viral gene expression would represent an ultimate in immune evasion strategies, is not sufficient for lifelong persistence and dissemination of the virus. CMV needs to reactivate and replicate in a lytic cycle of infection in order to disseminate further, which occurs in the face of a fully primed secondary immune response. Without reactivation, latency itself would be redundant for the virus. It is also becoming clear that latency is not a totally quiescent state, but is characterized by limited viral gene expression. Therefore, the virus also needs immune evasion strategies during latency. An effective immune response to CMV is required or viral replication will cause morbidity and ultimately mortality in the host. There is clearly a complex balance between virus immune evasion and host immune recognition over a lifetime. This poses the important question of whether long-term evasion or manipulation of the immune response driven by CMV is detrimental to health. In this meeting report, three groups used the murine model of CMV (MCMV) to examine if the contribution of the virus to immune senescence is set by the (i) initial viral inoculum, (ii) inflation of T cell responses, (iii) or the balance between functionally distinct effector CD4+ T cells. The work of other groups studying the CMV response in humans is discussed. Their work asks whether the ability to make immune responses to new antigens is compromised by (i) age and HCMV carriage, (ii) long-term exposure to HCMV giving rise to an overall immunosuppressive environment and increased levels of latent virus, or (iii) adapted virus mutants (used as potential vaccines) that have the capacity to elicit conventional and unconventional T cell responses.

Description

Keywords

cytomegalovirus, immune evasion, aging, immune manipulation

Journal Title

GeroScience

Conference Name

Journal ISSN

2509-2715
2509-2723

Volume Title

39

Publisher

Springer
Sponsorship
Medical Research Council (MR/K021087/1)
Medical Research Council (G0701279)
DvB and SPHVdB are funded by a strategic program grant RIVM. MRW and SEJ are funded by the Medical Research Council Grant (GB) [MR/K021087/1]. The work summarized in the section titled BThe impact of aging on IL-10 secreting HCMV latent antigen specific T cells and latent viral load^ was supported by the Cambridge NIHR BRC Cell Phenotyping Hub. We gratefully acknowledge the participation of all Cambridge NIHR BioResource volunteers, and we thank the Cambridge BioResource staff for their help with volunteer recruitment. The Cambridge BioResource is funded by the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre (BRC) and the NHS Blood and Transplant (NHSBT). CAB is funded by an NIH grant AI101423. LCS was funded in part by grants from the Helmholtz Association (HGFVI-424) and the German Scientific Council (SFB900 TP B2).