title: Human interdigitating dendritic cells induce isotype switching and IL-13-dependent IgM production in CD40-activated naive B cells.
abstract: Interdigitating dendritic cells (IDC) represent a mature progeny of dendritic cells (DC) in vivo and are exhibiting a strong lymphocyte stimulatory potential. Because of the restricted localization to secondary lymphoid organs where decisive cellular interactions take place in the initial events of immunity, IDC regulatory function was addressed in relation to naive B cells. In this study, we demonstrate that human tonsillar IDC induce a dual response from CD40-activated IgD+/CD38- naive B lymphocytes. IDC direct naive B cells toward either isotype switching or an IL-13-dependent IgM secretion. IDC-dependent proliferation, isotype switching, and Ig production are all strictly mediated by soluble factors, suggesting that such skewing in B cell activation is the result of differential cytokine expression. Moreover, IDC-expressed IL-13 represents a novel source of a cytokine with recently established effects in Th2 induction as well as in immunological disorders resulting in allergic reactions.
authors.affiliation: Department of Immunotechnology, Lund University, Lund, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Johansson
authors.forename: S
authors.initials: S
authors.lastname: Ingvarsson
authors.forename: P
authors.initials: P
authors.lastname: Björck
authors.forename: C A
authors.initials: CA
authors.lastname: Borrebaeck
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism*; D019013:CD40 Antigens / Q000096:biosynthesis / Q000494:pharmacology*; D002469:Cell Separation; D018920:Coculture Techniques; D016207:Cytokines / Q000096:biosynthesis; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D017578:Immunoglobulin Class Switching / Q000276:immunology*; D007132:Immunoglobulin Isotypes / Q000096:biosynthesis*; D007075:Immunoglobulin M / Q000096:biosynthesis*; D007166:Immunosuppressive Agents / Q000494:pharmacology; D018793:Interleukin-13 / Q000276:immunology / Q000502:physiology*; D007399:Interphase / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology*; D012995:Solubility
chemical_list: D000911:Antibodies, Monoclonal; D019013:CD40 Antigens; D016207:Cytokines; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M; D007166:Immunosuppressive Agents; D018793:Interleukin-13