title: Expansion of regulatory T cells in aged mice following influenza infection.
abstract: While it has been established that Treg cells can down-modulate an immune response, no study has addressed if the observed increase in Treg cells in aged mice is related to the decreased and delayed specific CD8 T cell responses seen following primary influenza infection. In this study, phenotypic characteristics and function of Treg cells were analyzed in young (4-6 months) and aged (18-22 months) mice prior to and during the course of primary influenza infection. Upon infection, aged, but not young, mice have a significant expansion of Treg cells. In addition, Treg cells of aged mice demonstrate both a higher percentage and higher expression per cell of CD69 both at baseline and during infection compared to young mice. However, Treg cells isolated from young and aged mice comparably suppress CD8 T cells and suppression is dose dependent. These results suggest that the increase in the percentage of Treg cells in aged mice may contribute to the diminished CD8 T cell response to primary influenza infection.
authors.affiliation: Department of Biology, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Williams-Bey
authors.forename: Jiu
authors.initials: J
authors.lastname: Jiang
authors.forename: Donna M
authors.initials: DM
authors.lastname: Murasko
mesh_terms: D000375:Aging; D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000096:biosynthesis; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D004195:Disease Models, Animal; D051858:Forkhead Transcription Factors / Q000096:biosynthesis; D053645:Interleukin-2 Receptor alpha Subunit / Q000096:biosynthesis; D037181:Lectins, C-Type / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009976:Orthomyxoviridae Infections / Q000097:blood*; D010641:Phenotype; D013154:Spleen / Q000166:cytology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000821:virology; D013997:Time Factors; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D051858:Forkhead Transcription Factors; D053645:Interleukin-2 Receptor alpha Subunit; D037181:Lectins, C-Type; D000099192:CD69 Antigens; C498833:Foxp3 protein, mouse