FOXO3a, a forkhead transcription factor and member of the forkhead box class O (FOXO) subfamily, has been shown to promote the translocation of p53 to the cytoplasm, thereby inducing the mitochondria-associated apoptotic pathway. However, the binding sites that mediate this interaction between FOXO3a and p53 have not been identified. Here, we show that two regions within FOXO3a, the forkhead (F...

The Src homology 2 domain-containing inositol 5'-phosphatase (SHIP) is recruited to immunoreceptor tyrosine-based inhibition motif (ITIM)-containing proteins, thereby suppressing phosphatidylinositol 3-kinase (PI 3-kinase)-dependent pathways. The role of SHIP in phagocytosis, a PI 3-kinase-dependent pathway, is unknown. Overexpression of SHIP in macrophages led to an inhibition of phagocytosis ...

Anti-tumor mAbs hold promise for cancer therapy, but are relatively inefficient. Therefore, there is a need for agents that might amplify the effectiveness of these mAbs. One such agent is beta-glucan, a polysaccharide produced by fungi, yeast, and grains, but not mammalian cells. Beta-glucans are bound by C receptor 3 (CR3) and, in concert with target-associated complement fragment iC3b, elici...

Antitumor mAb bind to tumors and activate complement, coating tumors with iC3b. Intravenously administered yeast beta-1,3;1,6-glucan functions as an adjuvant for antitumor mAb by priming the inactivated C3b (iC3b) receptors (CR3; CD11b/CD18) of circulating granulocytes, enabling CR3 to trigger cytotoxicity of iC3b-coated tumors. Recent data indicated that barley beta-1,3;1,4-glucan given orally...

The role of the complement receptor type 3 (CR3) on thioglycollate-elicited peritoneal macrophages (TG-PM) in the destruction of opsonized particles was studied. We found that sheep red blood cells (E) that were opsonized with an IgM monoclonal antiForssman antibody and complement (E-IgM-C) were lysed by TG-PM, whereas there was little lysis of E pretreated with either the antibody or the eompl...

Myelotoxic injury in the bone marrow (BM) as a consequence of total body irradiation (TBI) or granulocyte colonystimulating factor (G-CSF) mobilization results in the deposition of iC3b on BM stroma (stroma-iC3b). In the present study, we have examined how stromaiC3b interacts with hematopoietic progenitor cells (HPCs) and the role of complement (C) and complement receptor 3 (CR3) in BM injury/...

The adherence of Bordetella pertussis to human respiratory cilia is critical to the pathogenesis of whooping cough but the significance of bacterial attachment to macrophages has not been determined. Adherence to cilia and macrophages is mediated by two large, nonfimbrial bacterial proteins, filamentous hemagglutinin (FHA), and pertussis toxin (PT). PT and FHA both recognize carbohydrates on ci...

abstract effect of cr3+ concentrations (1, 2, 4, 6, and 8 mg l-1) on lipid peroxidation / mda production and antioxidative enzyme activity (apox, sod, and ppox) in root and leaf tissues of sweet basil seedlings (ocimum basilicum l.) during 6week treatment in hydroponic culture was studied. increasing cr3+ in the culture medium (≥4 mg l-1) caused significant enhancement of apox, sod, and ppox ac...

A lectin function within CD11b mediates both cytotoxic priming of Mac-1/complement receptor type 3 (CR3) by beta-glucan and the formation of transmembrane signaling complexes with GPI-anchored glycoproteins such as CD16b (FcgammaRIIIb). A requirement for GPI-anchored urokinase plasminogen activator receptor (uPAR; CD87) in neutrophil adhesion and diapedesis has been demonstrated with uPAR-knock...

Macrophages, dendritic cells, and neutrophils use phagocytosis to capture and clear off invading pathogens. The process is triggered by the interaction of ligands on the pathogens' surface with specific phagocytic receptors, including immunoglobulin (FcR) and complement C3bi (CR3) receptors (integrin alpha(M)beta2, Mac1) . Localized actin-filament assembly that acts as the driving force for par...