Fcγ Receptor IIb Strongly Regulates Fcγ Receptor-Facilitated T Cell Activation by Dendritic Cells

Fcγ receptor IIb strongly regulates Fcγ receptor-facilitated T cell activation by dendritic cells.

FcγR ligation by Ag-Ab immune complexes (IC) not only mediates effective Ag uptake, but also strongly initiates dendritic cell (DC) maturation, a requirement for effective T cell activation. Besides the activating FcγRI, FcγRIII, and FcγRIV, the inhibitory FcγRIIb is expressed on DCs. It is unclear how the ratio between signals from the activating FcγR and the inhibitory FcγRIIb determines the ...

Fcg Receptor IIb Strongly Regulates Fcg Receptor- Facilitated T Cell Activation by Dendritic Cells

Coupling of Fcγ receptor I to Fcγ receptor IIb by SRC kinase mediates C-reactive protein impairment of endothelial function.

RATIONALE Elevations in C-reactive protein (CRP) are associated with increased cardiovascular disease risk and endothelial dysfunction. CRP antagonizes endothelial nitric oxide synthase (eNOS) through processes mediated by the IgG receptor Fcγ receptor IIB (FcγRIIB), its immunoreceptor tyrosine-based inhibitory motif, and SH2 domain-containing inositol 5'-phosphatase 1. In mice, CRP actions on ...

Antigen-Specific IgG ameliorates allergic airway inflammation via Fcγ receptor IIB on dendritic cells

BACKGROUND There have been few reports on the role of Fc receptors (FcRs) and immunoglobulin G (IgG) in asthma. The purpose of this study is to clarify the role of inhibitory FcRs and antigen presenting cells (APCs) in pathogenesis of asthma and to evaluate antigen-transporting and presenting capacity by APCs in the tracheobronchial mucosa. METHODS In FcγRIIB deficient (KO) and C57BL/6 (WT) m...

Fcγ Receptor Heterogeneity in Leukocyte Functional Responses

Antibodies participate in defense of the organism from all types of pathogens, including viruses, bacteria, fungi, and protozoa. IgG antibodies recognize their associated antigen via their two Fab portions and are in turn recognized though their Fc portion by specific Fcγ receptors (FcγRs) on the membrane of immune cells. Multiple types and polymorphic variants of FcγR exist. These receptors ar...