scholarly journals Immunochemical characterization of mucins. Polypeptide (M1) and polysaccharide (A and Leb) antigens

1988 ◽  
Vol 254 (1) ◽  
pp. 185-193 ◽  
Author(s):  
J Bara ◽  
R Gautier ◽  
J Le Pendu ◽  
R Oriol
Keyword(s):  
Monoclonal Antibodies ◽  
Molecular Mass ◽  
High Molecular Mass ◽  
Density Gradient Ultracentrifugation ◽  
Blood Group Antigens ◽  
Lewis Blood Group ◽  
Progressive Loss ◽  
Cscl Density Gradient ◽  
Mucinous Cyst

Seven monoclonal antibodies (MAbs) reacting with high-molecular-mass components (greater than 20,000 kDa) isolated from an ovarian mucinous cyst of an A Le(a-b+) patient are described. By the use of immunoradiometric methods, these MAbs characterized seven different epitopes associated with components having a density of 1.45 g/ml by CsCl-density-gradient ultracentrifugation, like mucins. Two MAbs reacted with A and Lewis blood-group antigens respectively (polysaccharide epitopes). The five other MAbs characterized five M1 epitopes (called a, b, c, d and e), mainly associated with components of more than 20,000 kDa and 2000 kDa. They were completely destroyed by papain and 2-mercaptoethanol treatment (polypeptide epitopes). Moreover, timed trypsin digestion of native mucin resulted in a progressive loss of M1 activity and degraded these mucins into smaller M1-positive fragments. The a and c epitopes were partially degraded from relatively high-molecular-mass fragments (2000 kDa to 500 kDa) into a 100 kDa fragment. The b and d epitopes were completely degraded into smaller fragments ranging from 100 kDa to 40 kDa. The e epitope was completely destroyed by trypsin. These different pathways of M1 antigen degradation suggest the occurrence of different epitopes located in separate regions of the mucin molecules.

scholarly journals Mucins secreted by a transformed cell line derived from human tracheal gland cells1

1997 ◽  
Vol 326 (2) ◽  
pp. 431-437 ◽  
Author(s):  
Jean-Marc LO-GUIDICE ◽  
Marc D. MERTEN ◽  
Geneviève LAMBLIN ◽  
Nicole PORCHET ◽  
Marie-Christine HOUVENAGHEL ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Cell Line ◽  
Density Gradient ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Buoyant Density ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
High Molecular Mass ◽  
Cscl Density Gradient

High-molecular-mass glycoconjugates are secreted by the continuous cell line MM-39, which has been obtained from cultured human tracheal gland cells transformed by simian virus 40. They were purified on Sepharose® CL-4B and then by two steps of density-gradient centrifugation. High-molecular-mass glycoproteins resistant to digestion by hyaluronidase, chondroitin ABC lyase and heparitinase were obtained, in addition to hyaluronic acid and proteoglycans. They were susceptible to β-elimination. They contained polylactosaminoglycan chains as well as carbohydrate chains with a terminal sialic acid in the NeuAc α2-3 sequence. Most of them have a buoyant density of 1.45 g/ml in CsCl-density-gradient centrifugation, except for MUC1. The MM-39 cells were also characterized by a high expression of MUC1 and MUC4 genes, but they did not express MUC2, MUC3, MUC5B and MUC5AC. Therefore the MM-39 cells synthesized mucin-like glycoproteins as well as lysozyme and mucous proteinase inhibitor [Merten, Kammouni, Renaud, Birg, Mattéi and Figarella (1996) Am. J. Respir. Cell. Mol. Biol. 15, 520–528]; they should be considered as having a mixed, both serous and mucous, phenotype.

scholarly journals Characterization of derivatives of the high-molecular-mass penicillin-binding protein (PBP) 1 of Mycobacterium leprae

2000 ◽  
Vol 350 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Sebabrata MAHAPATRA ◽  
Sanjib BHAKTA ◽  
Jasimuddin AHAMED ◽  
Joyoti BASU
Keyword(s):  
Plasma Membrane ◽  
Molecular Mass ◽  
Mycobacterium Leprae ◽  
Binding Activity ◽  
High Molecular Mass ◽  
Class A ◽  
C Terminus ◽  
Fusion Junction ◽  
Derivatives Of

Mycobacterium leprae has two high-molecular-mass multimodular penicillin-binding proteins (PBPs) of class A, termed PBP1 and PBP1* [Lepage, Dubois, Ghosh, Joris, Mahapatra, Kundu, Basu, Chakrabarti, Cole, Nguyen-Disteche and Ghuysen (1997) J. Bacteriol. 179, 4627–4630]. PBP1-Xaa–β-lactamase fusions generated periplasmic β-lactamase activity when Xaa (the amino acid of PBP1 at the fusion junction) was residue 314, 363, 407, 450 or 480. Truncation of the N-terminal part of the protein up to residue Leu-147 generated a penicillin-binding polypeptide which could still associate with the plasma membrane, whereas [∆M1–R314]PBP1 (PBP1 lacking residues Met-1 to Arg-314) failed to associate with the membrane, suggesting that the region between residues Leu-147 and Arg-314 harbours an additional plasma membrane association site for PBP1. Truncation of the C-terminus up to 42 residues downstream of the KTG (Lys-Thr-Gly) motif also generated a polypeptide that retained penicillin-binding activity. [∆M1–R314]PBP1 could be extracted from inclusion bodies and refolded under appropriate conditions to give a form capable of binding penicillin with the same efficiency as full-length PBP1. This is, to the best of our knowledge, the first report of a soluble derivative of a penicillin-resistant high-molecular-mass PBP of class A that is capable of binding penicillin. A chimaeric PBP in which the penicillin-binding (PB) module of PBP1 was fused at its N-terminal end with the non-penicillin-binding (n-PB) module of PBP1* retained pencillin-binding activity similar to that of PBP1, corroborating the finding that the n-PB module of PBP1 is dispensable for its penicillin-binding activity.

Characterization of murine monoclonal antibodies againstHelicobacter pylorilipopolysaccharide specific for Lexand Leyblood group determinants

2005 ◽  
Vol 83 (5) ◽  
pp. 589-596 ◽  
Author(s):  
Eleonora Altman ◽  
Blair A Harrison ◽  
Tomoko Hirama ◽  
Vandana Chandan ◽  
Rebecca To ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Monoclonal Antibodies ◽  
Blood Group ◽  
Cell Envelope ◽  
Mucosal Cell ◽  
Blood Group Antigens ◽  
Binding Characteristics ◽  
Igg3 Subclass ◽  
H Pylori

The cell envelope of Helicobacter pylori contains lipopolysaccharide (LPS), the O-chain of which expresses type 2 Lexand Leyblood group antigens, which mimic human gastric mucosal cell-surface glycoconjugates and may contribute to the survival of H. pylori in gastric mucosa. Here we describe the generation of monoclonal antibodies specific for Lexand Leyblood group determinants and the characterization of their binding properties using purified, structurally defined H. pylori LPS, synthetic glycoconjugates, and H. pylori cells. Analysis of oligosaccharide binding by SPR provided a rapid and reliable means for characterization of antibody affinities. One of the antibodies, anti-Lex, was of IgG3 subclass and had superior binding characteristics as compared with the commercially available anti-LexIgM. These antibodies could have potential in the immunodiagnosis of certain types of cancer, in serotyping of H. pylori isolates, and in structure–function studies.Key words: Helicobacter pylori, lipopolysaccharide, monoclonal antibodies, Lewis determinants, immunodiagnosis.

Sign in / Sign up

Export Citation Format

Share Document