Influenza infection of beta 2-microglobulin-deficient (beta 2m-/-) mice reveals a loss of CD4+ T cell functions with aging.
J Immunol
; 159(7): 3453-9, 1997 Oct 01.
Article
en En
| MEDLINE
| ID: mdl-9317144
Following influenza infection, aged mice have prolonged viral shedding that is presumably due to lower anti-influenza class I-restricted CD8+ CTL activity. To examine alternative viral clearance mechanisms in immunosenescense, we infected young (1.5-2.5 month) and aged (15-18 month) class I and CD8+-deficient beta 2m-/- mice with influenza A/Port Chalmers/1/73 (H3N2). We found that 40% of young beta 2m-/- mice were shedding virus from the lung on day 9 (mean titer of 0.3 log10 TCID[50]), with a maximal anti-influenza class II CTL activity of 68+/-2% on day 7. In contrast, 100% of aged beta 2m-/- mice were still shedding virus (mean titer of 3.0 log10 TCID[50]) from the lung on day 9 with a peak CTL activity of 15+/-6%. Aged beta 2m-/- mice also had significantly lower pulmonary IFN-gamma levels, serum anti-influenza neutralizing Ab, and anti-influenza mucosal IgA titers, as well as a less intense pulmonary inflammatory response on early days of infection. Th2-mediated cytokines were dysregulated. We conclude that there are multiple mechanisms responsible for the age-related delay in recovery from influenza. These include decreased anti-influenza class II-restricted CTL activity, pulmonary IFN-gamma levels, and serum neutralizing Ab. Taken together, these findings show a loss of CD4+ T cell functions with aging.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Virus de la Influenza A
/
Envejecimiento
/
Linfocitos T CD4-Positivos
/
Microglobulina beta-2
/
Infecciones por Orthomyxoviridae
Límite:
Animals
Idioma:
En
Revista:
J Immunol
Año:
1997
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos