Mannan-binding protein, a C-type serum lectin, recognizes primary colorectal carcinomas through tumor-associated Lewis glycans.

Mannan (mannose)-binding protein (MBP) is a C-type serum lectin that plays a key role in innate immunity. MBP forms large multimers (200-600 kDa) and exhibits broad specificity for mannose, N-acetylglucosamine, and fucose. MBP exhibits high affinity for unique oligosaccharides that have been isolated from human colorectal carcinoma (SW1116) cells and characterized as highly fucosylated high m.

Dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) recognizes a novel ligand, Mac-2-binding protein, characteristically expressed on human colorectal carcinomas.

Dendritic cell (DC)-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) is a type II transmembrane C-type lectin expressed on DCs such as myeloid DCs and monocyte-derived DCs (MoDCs). Recently, we have reported that DC-SIGN interacts with carcinoembryonic antigen (CEA) expressed on colorectal carcinoma cells. CEA is one of the most widely used tumor markers for gastrointestinal cancers such as colorectal cancer.

A novel mitogen fusion protein against CD40+ cells with potent vaccine adjuvant properties.

A large number of infectious diseases caused by viral or bacterial infections are treatable and/or preventable by vaccination. In addition, ongoing research is aimed at the development of vaccines against other types of diseases, including almost all forms of cancer. The efficacy of a vaccine relies on the antigen-specific response by the entire repertoire of immune competent cells.

Characterization of the interaction between serum mannan-binding protein and nucleic acid ligands.

Serum MBP, also known as MBL, is a C-type lectin that is known to be a soluble host defense factor involved in innate immunity. It has been well established that dying microbes and apoptotic cells release highly viscous DNA that induces inflammation and septic shock, and apoptotic cells display fragmented DNA on their surfaces. However, PRRs that mediate the recognition and clearance of free DNA and fragmented DNA in apoptotic cells have not been characterized clearly.

The lectin Jacalin induces human B-lymphocyte apoptosis through glycosylation-dependent interaction with CD45.

It has been well established that CD45 is a key receptor-type protein tyrosine phosphatase (PTPase) regulating Src-family protein tyrosine kinase (Src-PTK) in T and B lymphocytes. However, precisely how CD45 exerts its effect in these lymphocytes remains controversial. We recently reported that Jacalin, an alpha-O-glycoside of the disaccharide Thomsen-Friedenreich antigen-specific lectin from jackfruit seeds, caused marked T-cell activation in response to T-cell receptor ligation and CD28 costimulation by binding to CD45.

Highly fucosylated N-glycan ligands for mannan-binding protein expressed specifically on CD26 (DPPVI) isolated from a human colorectal carcinoma cell line, SW1116.

The serum mannan-binding protein (MBP) is a host defense C-type lectin specific for mannose, N-acetylglucosamine, and fucose residues, and exhibits growth inhibitory activity toward human colorectal carcinoma cells. The MBP-ligand oligosaccharides (MLO) isolated from a human colorectal carcinoma cell line, SW1116, are large, multiantennary N-glycans with highly fucosylated polylactosamine-type structures having Le(b)-Le(a) or tandem repeats of the Le(a) structure at their nonreducing ends. In this study, we isolated the major MBP-ligand glycoproteins from SW1116 cell lysates with an MBP column and identified them as CD26/dipeptidyl peptidase IV (DPPIV) (110 kDa) and CD98 heavy chain (CD98hc)/4F2hc (82 kDa).

Glycosylation-dependent interactions of C-type lectin DC-SIGN with colorectal tumor-associated Lewis glycans impair the function and differentiation of monocyte-derived dendritic cells.

Dendritic cells (DCs) are APCs that play an essential role by bridging innate and adaptive immunity. DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) is one of the major C-type lectins expressed on DCs and exhibits high affinity for nonsialylated Lewis (Le) glycans. Recently, we reported the characterization of oligosaccharide ligands expressed on SW1116, a typical human colorectal carcinoma recognized by mannan-binding protein, which is a serum C-type lectin and has similar carbohydrate-recognition specificities as DC-SIGN.

Subcellular localization and physiological significance of intracellular mannan-binding protein.

Mannan-binding protein (MBP) is a C-type mammalian lectin specific for mannose and N-acetylglucosamine. MBP is mainly synthesized in the liver and occurs naturally in two forms, serum MBP (S-MBP) and intracellular MBP (I-MBP). S-MBP activates complement in association with MBP-associated serine proteases via the lectin pathway.

LPS suppresses expression of asialoglycoprotein-binding protein through TLR4 in thioglycolate-elicited peritoneal macrophages.

Macrophages are known to express various types of endocytosis receptors that mediate the removal of foreign pathogens. Macrophage asialoglycoprotein-binding protein (M-ASGP-BP) is a Gal/GalNAc-specific lectin, which functions as an endocytosis receptor. We found here that LPS is able to down-regulate the mRNA expression of M-ASGP-BP in a time-dependent manner using thioglycolate-elicited rat and mouse peritoneal macrophages.

Isolation, cloning, and characterization of a novel phosphomannan-binding lectin from porcine serum.

Mannan-binding protein (MBP) is a C-type serum lectin that is an important constituent of the innate immune defense because it activates the complement system via the lectin pathway. While the pig has been proposed to be an attractive source of xenotransplantable tissues and organs, little is known about porcine MBP. In our previous studies, phosphomannan, but not mannan, was found to be an effective inhibitor of the C1q-independent bactericidal activity of newborn piglet serum against some rough strains of Gram-negative bacteria.

Glycosylation-dependent interaction of Jacalin with CD45 induces T lymphocyte activation and Th1/Th2 cytokine secretion.

Jacalin, an alpha-O-glycoside of the disaccharide Thomsen-Friedenreich antigen (galactose beta1-3 N-acetylgalactosamine, T-antigen)-specific lectin from jackfruit seeds, has been shown to induce mitogenic responses and to block infection by HIV-1 in CD4+ T lymphocytes. The molecular mechanism underlying Jacalin-induced T cell activation has not been elucidated completely yet. In the present study, protein tyrosine phosphatase (PTPase) CD45 was isolated from a Jurkat T cell membrane fraction as a major receptor for Jacalin through affinity chromatography and mass spectrometry.

Mannan-binding protein blocks the activation of metalloproteases meprin alpha and beta.

Mannan-binding protein (MBP) is a C-type serum lectin that is known to be a host defense factor involved in innate immunity, and recognizes mannose, fucose, and N-acetylglucosamine residues. Although some exogenous MBP ligands have been reported, little is known about its endogenous ligands. In the present study, we found that endogenous MBP ligands are highly expressed in the brush border epithelial cells of kidney-proximal tubules by immunohistochemistry, and both meprin alpha and beta (meprins), as novel endogenous MBP ligands, have been identified through affinity chromatography and mass spectrometry.

Superoxide production from human polymorphonuclear leukocytes by human mannan-binding protein (MBP).

Mannan-binding protein (MBP) is a Ca(2+)-dependent mammalian lectin that plays an important role in innate immunity. In this study, we found that ligand-bound MBP stimulates polymorphonuclear leukocytes (PMN) to induce cell aggregation and superoxide production. The biological response of PMN to ligand-bound MBP was dose- and time-dependent.

Role of mannan-binding protein, MBP, in innate immunity.

Mannan-binding protein (MBP) is a C-type lectin, which binds to carbohydrates on the surface of some microorganisms and kills them through the activation of complement. This complement activation pathway is called the lectin pathway. MBP also kills mammalian cells that express MBP ligands on their surfaces via the lectin pathway.