title: Atomic force microscopy to study the effects of ITIM-bearing FcgammaRIIB on the activation of RBL-2H3 cells.
abstract: We have studied here the effects of ITIM-bearing FcgammaRIIB2 on the FcvarepsilonRI-dependent activation of rat basophilic leukemia (RBL-2H3) cells by atomic force microscopy (AFM). AFM images showed that ruffling and degranulation of RBL-2H3 cells were significantly reduced but the cell spreading was not by the co-clustering of FcgammaRIIB2 and FcvarepsilonRI. From the results it was shown that the co-clustering of ITIM-bearing negative co-receptors in a single RBL cell hardly induce the degranulation though the [Ca(2+)](i) increased transiently in the cell. This suggested that secretory responses and the membrane ruffling which were induced by the crosslinkng of FcgammaRII should be negatively controlled by the co-clustering of FcgammaRII.
authors.affiliation: Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, 467-8603, Nagoya, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Nakamura
authors.forename: M
authors.initials: M
authors.lastname: Nakanishi
mesh_terms: D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology / Q000494:pharmacology; D015703:Antigens, CD / Q000276:immunology*; D015549:Basophil Degranulation Test; D001491:Basophils / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D015550:Cell Degranulation / Q000187:drug effects / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology / Q000494:pharmacology; D051379:Mice; D018625:Microscopy, Atomic Force / Q000379:methods; D010047:Ovalbumin / Q000276:immunology / Q000494:pharmacology; D051381:Rats; D017455:Receptors, IgE / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology*; D013050:Spectrometry, Fluorescence / Q000379:methods; D014407:Tumor Cells, Cultured
chemical_list: D000936:Antigen-Antibody Complex; D015703:Antigens, CD; C080571:Fc gamma receptor IIB; D007074:Immunoglobulin G; D017455:Receptors, IgE; D017452:Receptors, IgG; C038600:trinitrophenyl-ovalbumin; D010047:Ovalbumin