Variation rhythms of lymphocyte subsets during healthy aging.
Immunological alterations associated with aging (immunosenescence) do not represent a simple unidirectional decline in all functions but develop as a complex remodeling of the immune system, involving multiple reorganization and developmentally regulated changes. In general, most data available about aging were obtained at particular age intervals and most of them come from Caucasian individuals from either Europe or the United States. Here, we report the frequencies of major lymphocyte subsets in healthy Brazilian individuals from 2 distinct geographic regions (Southeast and South) at several age intervals spanning a lifetime period (0-86 years). Overall, we demonstrated that changes in the frequencies of cells related to both innate and adaptive immunity clearly occur with aging in these individuals. These changes were not progressive and equally steady for all cell populations tested but instead showed an oscillatory or rhythmic behavior that was distinctive of each population at different age intervals. We also observed that abrupt changes in the frequencies of immune cells may occur in healthy individuals over 75 years old, suggesting there is an impaired flexibility of the immune system at late stages of life to sustain homeostasis via immune mechanisms. We presented reference ranges for healthy Brazilian individuals at all ages. The knowledge of these parameters in further detail will allow interventions to optimize immune function in advanced age and to improve the quality of life in the elderly.
Faria
Ana Maria Caetano
AM
Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. afaria@icb.ufmg.br
de Moraes
Sara Monteiro
SM
de Freitas
Ludmila Helene Ferreira
LH
Speziali
Elaine
E
Soares
Taciana Figueiredo
TF
Figueiredo-Neves
Suzane Pretti
SP
Vitelli-Avelar
Danielle Marquete
DM
Martins
Marina Angela
MA
Barbosa
Kátia Valéria Bastos Dias
KV
Soares
Eric Basseti
EB
Sathler-Avelar
Renato
R
Peruhype-Magalhães
Vanessa
V
Cardoso
Glenda Meira
GM
Comin
Fabiano
F
Teixeira
Rosângela
R
Elói-Santos
Silvana Maria
SM
Queiroz
Dulciene Maria Magalhães
DM
Corrêa-Oliveira
Rodrigo
R
Bauer
Moisés Evandro
ME
Teixeira-Carvalho
Andréa
A
Martins-Filho
Olindo Assis
OA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000276:immunology*; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007121:Immunocompetence; D016130:Immunophenotyping; D007223:Infant; D007231:Infant, Newborn; D007694:Killer Cells, Natural; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000166:cytology*; D008297:Male; D012016:Reference Values; D050378:T-Lymphocytes, Regulatory; D055815:Young Adult