title: Aging and innate immune cells.
abstract: The innate immune system serves an important role in preventing microbial invasion. However, it experiences significant changes with advancing age. Among the age-associated changes are: Aged macrophages and neutrophils have impaired respiratory burst and reactive nitrogen intermediates as a result of altered intracellular signaling, rendering them less able to destroy bacteria. Aged neutrophils are also less able to respond to rescue from apoptosis. Aged dendritic cells (DC) are less able to stimulate T and B cells. The altered T cell stimulation is a result of changes in human leukocyte antigen expression and cytokine production, and lower B cell stimulation is a result of changes in DC immune complex binding. Natural killer (NK) cells from the elderly are less capable of destroying tumor cells. NK T cells increase in number and have greater interleukin-4 production with age. Levels of various complement components are also altered with advancing age.
authors.affiliation: Department of Cellbiology, Loyola University Chicago, Stritch School of Medicine, Building 110, Room 4237, 2160 South First Avenue, Maywood, IL 60513, USA.
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Plackett
authors.forename: Eric D
authors.initials: ED
authors.lastname: Boehmer
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Faunce
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Kovacs
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D003165:Complement System Proteins / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D009504:Neutrophils / Q000276:immunology*
chemical_list: D003165:Complement System Proteins