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 Fc receptor IIB (Fc RIIB), its immunoreceptor tyrosine-based inhibitory motif, and SH2 domaincontaining inositol 5 -phosphatase 1. In mice, CRP actions on e...

The allergic response is distinct from other immune reactions in its reliance on IgE, its high affinity receptor, Fc epsilon RI, and the primary effector cell--the tissue mast cell. Positive skin tests or raised concentrations of specific immunoglobulin E (IgE) in the serum define IgE sensitisation or "atopy". IgE participates both in immediate hypersensitivity response and in the induction of ...

Motivation: Children with systemic juvenile idiopathic arthritis (SJIA) are affected by a wide-range of complications. Partially arising from the difficulty of diagnosis due to the idiopathic nature of the indication. There may be a genetic basis for SJIA, which could help in both diagnosis, and treatment. Results: Two mutations in the Fc epsilon RI pathway, including PIK3CD, were detected in l...

Lymphocytes from normal nonallergic donors and patients with atopic disorders were analyzed for subpopulations bearing Fc receptors for immunoglobulin (Ig)E (Fc(epsilon)) and IgG (Fc(gamma)), surface IgM (sIgM) and IgD (sIgD), and for T cells forming spontaneous rosettes with sheep erythrocytes (E). The patients were divided into three groups according to serum IgE concentrations and systemic c...

Macrophage Fc gamma receptors play a significant role in inflammation and host defense. One monocyte/macrophage Fc gamma receptor, Fc gamma RI, the binding site for monomeric IgG, appears to be especially responsive to modulatory signals by hormones and mediators. Since Factor XIIa is generated during inflammation, we studied the effect of XIIa on Fc gamma RI. Factor XIIa, in a concentration-de...

Polymorphonuclear neutrophils (PMNs) are important effector cells in host defense and the inflammatory response to antigen. The involvement of PMNs in inflammation is mediated mainly by the Fc receptor family, including IgE receptors. Recently, PMNs were shown to express two IgE receptors (CD23/Fc«RII and galectin-3). In allergic diseases, the dominant role of IgE has been mainly ascribed to it...

In mouse mast cells, both Fc e RI and Fc g RIII are abg 2 tetrameric complexes in which different a chains confer IgE or IgG ligand recognition while the signaling FcR b and g chains are identical. We used primarily noninvasive techniques (changes in body temperature, dye extravasation) to assess systemic anaphylactic responses in nonanesthetized wild-type, Fc e RI a chain 2 / 2 and FcR g chain...

Besides their phagocytic effector functions, myeloid cells have an essential role as accessory cells in the induction of optimal humoral immune responses by presenting captured antigens and activating lymphocytes. Antigen presentation by human monocytes was recently found to be enhanced in vitro through the high-affinity Fc receptor for IgG (Fc g RI; CD64), which is exclusively present on myelo...

Natural Abs represent the indigenous immune repertoire and are thus present at birth and persist throughout life. Previously, human autoantibodies to the domain of the high-affinity IgE receptor (Fc RI ) have been isolated from Ab libraries derived from normal donors and patients with chronic urticaria. To investigate whether these anti-Fc RI Abs are present in the germline repertoire, we const...