Search results for "Recombinant protein"
showing 10 items of 707 documents
Common genetic denominators for Ca++-based skeleton in Metazoa: role of osteoclast-stimulating factor and of carbonic anhydrase in a calcareous spong…
2012
Calcium-based matrices serve predominantly as inorganic, hard skeletal systems in Metazoa from calcareous sponges [phylum Porifera; class Calcarea] to proto- and deuterostomian multicellular animals. The calcareous sponges form their skeletal elements, the spicules, from amorphous calcium carbonate (ACC). Treatment of spicules from Sycon raphanus with sodium hypochlorite (NaOCl) results in the disintegration of the ACC in those skeletal elements. Until now a distinct protein/enzyme involved in ACC metabolism could not been identified in those animals. We applied the technique of phage display combinatorial libraries to identify oligopeptides that bind to NaOCl-treated spicules: those oligop…
Mitochondrial glutathione depletion by glutamine in growing tumor cells.
2000
The effect of L-glutamine (Gln) on mitochondrial glutathione (mtGSH) levels in tumor cells was studied in vivo in Ehrlich ascites tumor (EAT)-bearing mice. Tumor growth was similar in mice fed a Gln-enriched diet (GED; where 30% of the total dietary nitrogen was from Gln) or a nutritionally complete elemental diet (SD). As compared with non-tumor-bearing mice, tumor growth caused a decrease of blood Gln levels in mice fed an SD but not in those fed a GED. Tumor cells in mice fed a GED showed higher glutaminase and lower Gln synthetase activities than did cells isolated from mice fed an SD. Cytosolic glutamate concentration was 2-fold higher in tumor cells from mice fed a GED ( approximately…
CrELISA: a fast and robust enzyme-linked immunosorbent assay bypassing the need for purification of recombinant protein
2004
A multitude of antigens has been recently identified by screening of cDNA expression libraries derived from human tumors with autologous sera. Using a phage autoantibody assay and small panels of sera derived from cancer patients or controls it has been shown that some of these antigens display cancer-associated autoantibody responses. The diagnostic and prognostic significance of these potentially cancer-related autoantibodies remains unclear until large-scale assays are developed and serological data are available for hundreds of cancer patients and controls. The major bottleneck for the development of large-scale assays are the cloning, expression and the purification of each of the resp…
Specific bovine antibody response against a new recombinant Cryptosporidium parvum antigen containing 4 zinc-finger motifs
2002
A Cryptosporidium parvum sporozoite and oocyst lambda gt11 cDNA library was screened with a hyperimmune rabbit serum that was developed against insoluble fragments of ultrasonicated oocysts. A clone named Cp22.4.1 encoding a protein of 231 amino acids with 4 zinc-finger domains characterized by a Cys-X2-Cys-X4-His-X4-Cys motif was isolated and characterized. There was a complete match between the sequencing data of the coding region of Cp22.4.1 and the corresponding gene at chromosomal level. Cloning in a pBAD-TOPO-TA expression vector permitted to evaluate the antigenicity of the recombinant His-tagged antigen. This antigen was recognized by 2 out of 5 sera from Cryptosporidium immune calv…
Function of Dipeptidyl Peptidase IV (CD26, Tp103) in Transfected Human T Cells
1993
CD26 (Tp103) is a proteolytic enzyme (dipeptidyl peptidase IV) expressed on the T cell surface that defines an alternative activation signal for human T lymphocytes. It is absent from or present in only low amounts on resting T cells but it is expressed strongly after activation. Crosslinking of CD26/Tp103 via the monoclonal antibody CB.1 triggers functional activities in preactivated T cells. To study the molecular requirements for T cell activation via CD26 we transfected a cDNA encoding CD26 into several CD26-negative cells. In Jurkat T cell leukemia cells that normally do not express the CD26 antigen, the transfected CD26 molecule is functional because the monoclonal antibody CB.1 induc…
INFγ stimulates arginine transport through system y+L in human monocytes
2004
Freshly isolated human monocytes transport L-arginine mostly through a sodium independent, NEM insensitive pathway inhibited by L-leucine in the presence, but not in the absence of sodium. Interferon-gamma (IFNgamma) stimulates this pathway, identifiable with system y+L, and markedly enhances the expression of SLC7A7, the gene that encodes for system y+L subunit y+LAT1, but not of SLC7A6, that codes for the alternative subunit y+LAT2. System y+ plays a minor role in arginine uptake by monocytes and the expression of system y+-related genes, SLC7A1 and SLC7A2, is not changed by IFNgamma. These results demonstrate that system y+L is sensitive to IFNgamma.
Enzyme replacement therapy for mucopolysaccharidosis VI: evaluation of long-term pulmonary function in patients treated with recombinant human N-acet…
2010
Pulmonary function is impaired in untreated mucopolysaccharidosis type VI (MPS VI). Pulmonary function was studied in patients during long-term enzyme replacement therapy (ERT) with recombinant human arylsulfatase B (rhASB; rhN-acetylgalactosamine 4-sulfatase). Pulmonary function tests prior to and for up to 240 weeks of weekly infusions of rhASB at 1 mg/kg were completed in 56 patients during Phase 1/2, Phase 2, Phase 3 and Phase 3 Extension trials of rhASB and the Survey Study. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and, in a subset of patients, maximum voluntary ventilation (MVV), were analyzed as absolute volume in liters. FEV1 and FVC showed little change f…
Receptor phosphorylation does not mediate cross talk between muscarinic M(3) and bradykinin B(2) receptors.
1999
This study examined cross talk between phospholipase C-coupled muscarinic M3and bradykinin B2receptors coexpressed in Chinese hamster ovary (CHO) cells. Agonists of either receptor enhanced phosphoinositide signaling (which rapidly desensitized) and caused protein kinase C (PKC)-independent, homologous receptor phosphorylation. Muscarinic M3but not bradykinin B2receptors were also phosphorylated after phorbol ester activation of PKC. Consistent with this, muscarinic M3receptors were phosphorylated in a PKC-dependent fashion after bradykinin B2receptor activation, but muscarinic M3receptor activation did not influence bradykinin B2receptor phosphorylation. Despite heterologous phosphorylatio…
Autoimmunity seen through the SEREX-scope.
2003
Autoantibodies can be detected in autoimmune diseases with a long prodromal phase and may serve as early indicators of disease activity. Autoantibody-based screening methods are therefore potent tools for the identification of target antigens. The SEREX method (serological identification of antigens by recombinant expression cloning) has been developed for the serological definition of immunogenic tumor antigens. Recent studies indicate that the SEREX approach may also be utilized for the analysis of complex immune responses involved in autoimmune diseases.
Delineation of the catalytic domain of Clostridium difficile toxin B-10463 to an enzymatically active N-terminal 467 amino acid fragment.
2006
Abstract In an attempt to directly approach the postulated toxic domain of Clostridium difficile 's TcdB-10463, eight subclones of different size and locations in the N-terminal third of the toxin were generated. Expression of these toxin fragments was checked in Western blots and the enzymatic activity of the expressed proteins was analyzed by glucosylating Ras related small GTP-binding proteins. Two polypeptides of 875 aa (TcdBc1–3) and 557 aa (TcdBc1-H) glucosylated their targets Rho, Rac and Cdc42 with the same activity and specificity as the holotoxin. In comparison 516 aa (TcdBc1-N) and 467 aa (TcdBc1-A) protein fragments exhibited highly reduced activity, while Tcdc1 and TcdB2–3 (aa …