title: Relationship between functional ability in older people, immune system status, and intensity of response to CMV.
abstract: Shorter survival in the elderly has been associated with deterioration of the immune system and also with functional disability. To analyze the relationship between functional and immune impairment in older individuals, we studied 100 elderly who lived in a nursing home, were age matched, and grouped according to their functional status. We characterized cell subpopulations by flow cytometry, quantified TREC by RT-PCR, and measured the T-cell proliferation and activation response (IFN-γ by ELISPOT, CD69) against anti-CD3 and CMV. Specific antibody titers against influenza virus and CMV were determined by ELISA. Individuals with worse functional status had significantly higher levels of NK cells and fewer B cells. These poorly functioning elders also had a significantly lower proportion of CD4+ T cells, increased CD8+ T cells, and a decreased CD4/CD8 ratio. TREC levels in CD4+ T cells were significantly lower in individuals with a high disability. Lower TREC levels correlated with a lower frequency of naïve T-cell subpopulations (CD45RA+CCR7+) and higher percentages of effector cells (CD45RA-CCR7-). The functionally impaired group had lower anti-CD3 responses, but gradually increased responses against CMV. Similarly, the higher CMV titers were found in elderly with worse functional status. On the contrary, the functional response in vivo, and the titer of antibodies generated after vaccination against influenza virus, was higher in individuals with better performance status. In summary, we concluded that the functional decline of elderly individuals was clearly associated with the aging of their immune system, and the intensity of the response to CMV.
authors.affiliation: Immunology Department, Hospital Universitario Central de Asturias, Oviedo, Spain.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Moro-García
authors.forename: Rebeca
authors.initials: R
authors.lastname: Alonso-Arias
authors.forename: Antonio
authors.initials: A
authors.lastname: López-Vázquez
authors.forename: Francisco Manuel
authors.initials: FM
authors.lastname: Suárez-García
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Solano-Jaurrieta
authors.forename: José
authors.initials: J
authors.lastname: Baltar
authors.forename: Carlos
authors.initials: C
authors.lastname: López-Larrea
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000914:Antibodies, Viral / Q000032:analysis; D003587:Cytomegalovirus / Q000502:physiology*; D003586:Cytomegalovirus Infections / Q000276:immunology*; D004279:DNA, Viral / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007111:Immunity, Cellular; D007156:Immunologic Memory; D008213:Lymphocyte Activation; D008297:Male; D051346:Mobility Limitation; D060888:Real-Time Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*; D017735:Virus Latency
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral