title: Atypical MHC class II-expressing antigen-presenting cells: can anything replace a dendritic cell?
abstract: Dendritic cells, macrophages and B cells are regarded as the classical antigen-presenting cells of the immune system. However, in recent years, there has been a rapid increase in the number of cell types that are suggested to present antigens on MHC class II molecules to CD4(+) T cells. In this Review, we describe the key characteristics that define an antigen-presenting cell by examining the functions of dendritic cells. We then examine the functions of the haematopoietic cells and non-haematopoietic cells that can express MHC class II molecules and that have been suggested to represent 'atypical' antigen-presenting cells. We consider whether any of these cell populations can prime naive CD4(+) T cells and, if not, question the effects that they do have on the development of immune responses.
authors.affiliation: Department of Pathology and Laboratory Medicine and Division of Rheumatology, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Taku
authors.initials: T
authors.lastname: Kambayashi
authors.affiliation: Philadelphia Veterans Affairs Medical Center, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Terri M
authors.initials: TM
authors.lastname: Laufer
mesh_terms: D017951:Antigen Presentation / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D001491:Basophils / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D004804:Eosinophils / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D008407:Mast Cells / Q000276:immunology; D009504:Neutrophils / Q000276:immunology
chemical_list: D000949:Histocompatibility Antigens Class II; D007073:Immunoglobulin E