title: Induction and enhancement of Fc(epsilon)RI-dependent mast cell degranulation following coculture with activated T cells: dependency on ICAM-1- and leukocyte function-associated antigen (LFA)-1-mediated heterotypic aggregation.
abstract: Activated mast cells are known to reside in close apposition to T cells in various inflammatory processes. In this regard, we have reported that activated mast cells form heterotypic aggregates with activated lymphocytes. To determine whether this interaction would result in mast cell degranulation, we examined the effect of EL-4, 2B4, or freshly isolated T cells, activated by PMA or immobilized anti-CD3 mAb, on histamine release from murine bone marrow-derived cultured mast cells (BMCMC). Coculturing BMCMC with activated but not with resting T cells resulted in significant histamine release. Also, Fc(epsilon)RI cross-linking-induced degranulation was augmented when BMCMC were cocultured with activated T cells. Supernatants of activated T cells failed to exert the stimulatory effect. Separation of the two cell populations with a porous membrane prevented degranulation, indicating that BMCMC activation was adhesion dependent. Indeed, the kinetics of histamine release paralleled the kinetics of the formation of heterotypic aggregates, which peaked after 12 h of coculture. Introduction of anti-LFA-1 and anti-intercellular adhesion molecule-1 mAb inhibited the adhesion-induced mast cell degranulation. These data suggest a heretofore unrecognized mast cell activation pathway induced by LFA-1/intercellular adhesion molecule-1-mediated heterotypic aggregation with activated T cells.
authors.affiliation: Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1881, USA.
authors.forename: N
authors.initials: N
authors.lastname: Inamura
authors.forename: Y A
authors.initials: YA
authors.lastname: Mekori
authors.forename: S P
authors.initials: SP
authors.lastname: Bhattacharyya
authors.forename: P J
authors.initials: PJ
authors.lastname: Bianchine
authors.forename: D D
authors.initials: DD
authors.lastname: Metcalfe
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D017252:CD3 Complex; D002449:Cell Aggregation; D002450:Cell Communication; D015550:Cell Degranulation; D002478:Cells, Cultured; D006636:Histamine Release; D018799:Intercellular Adhesion Molecule-1 / Q000502:physiology; D008213:Lymphocyte Activation; D016169:Lymphocyte Function-Associated Antigen-1 / Q000502:physiology; D008407:Mast Cells / Q000166:cytology / Q000276:immunology* / Q000502:physiology*; D051379:Mice; D017455:Receptors, IgE / Q000378:metabolism*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D016169:Lymphocyte Function-Associated Antigen-1; D017455:Receptors, IgE; D018799:Intercellular Adhesion Molecule-1