Valpha24+ NKT cells are decreased in elderly humans.
Natural killer T (NKT) cells represent a novel cell lineage characterized by the restricted expression of an invariant TCRalpha chain encoded by Valpha24/JalphaQ gene segments in humans and Valpha14/Jalpha281+ in mice. Different aspects of the immune response are severely affected by age. Thus, we have studied the effect of aging on NKT cells from healthy elderly individuals. Our results demonstrated a decreased percentage of CD3+Valpha24+ cells in peripheral blood from elderly donors, whereas mainstream T lymphocytes showed an age-associated decrease in the expression of CD28, the vast majority of CD3+Valpha24+ cells from old individuals were CD28+. A significant increase in the percentage of Valpha24+ cells with the CD4-CD8+ phenotype was also found in the elderly, indicating a redistribution of Valpha24+ subsets according to the CD4/CD8 phenotype. Given the important immunoregulatory role of these cells, the decrease of NKT cells will contribute to the deleterious immune response in the elderly.
DelaRosa
Olga
O
Department of Immunology, Faculty of Medicine, Reina Sofia University Hospital, University of Cordoba, Avda. Menéndez Pidal s/n, 14004 Cordoba, Spain.
Tarazona
Raquel
R
Casado
Javier G
JG
Alonso
Corona
C
Ostos
Belén
B
Peña
José
J
Solana
Rafael
R
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D018106:CD28 Antigens; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology* / Q000276:immunology; D018655:Lymphocyte Count; D016693:Receptors, Antigen, T-Cell, alpha-beta; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology
D015415:Biomarkers; D018106:CD28 Antigens; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta