Cross-presentation, dendritic cell subsets, and the generation of immunity to cellular antigens.
Cross-presentation involves the uptake and processing of exogenous antigens within the major histocompatibility complex (MHC) class I pathway. This process is primarily performed by dendritic cells (DCs), which are not a single cell type but may be divided into several distinct subsets. Those expressing CD8alpha together with CD205, found primarily in the T-cell areas of the spleen and lymph nodes, are the major subset responsible for cross-presenting cellular antigens. This ability is likely to be important for the generation of cytotoxic T-cell immunity to a variety of antigens, particularly those associated with viral infection, tumorigenesis, and DNA vaccination. At present, it is unclear whether the CD8alpha-expressing DC subset captures antigen directly from target cells or obtains it indirectly from intermediary DCs that traffic from peripheral sites. In this review, we examine the molecular basis for cross-presentation, discuss the role of DC subsets, and examine the contribution of this process to immunity, with some emphasis on DNA vaccination.
Heath
William R
WR
Department of Immunology and The Cooperative Research Center for Vaccine Technology, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia. heath@wehi.edu.au
Belz
Gabrielle T
GT
Behrens
Georg M N
GM
Smith
Christopher M
CM
Forehan
Simon P
SP
Parish
Ian A
IA
Davey
Gayle M
GM
Wilson
Nicholas S
NS
Carbone
Francis R
FR
Villadangos
Jose A
JA
D000818:Animals; D000941:Antigens / Q000276:immunology*; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology; D045142:Cross-Priming / Q000276:immunology*; D003713:Dendritic Cells / Q000145:classification / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology; D006801:Humans; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*
D000941:Antigens; D000954:Antigens, Surface; D015395:Histocompatibility Antigens Class I; D019444:Vaccines, DNA