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Li S, Xiong F, Zhang S, Liu J, Gao G, Xie J, Wang Y. Oligonucleotide therapies for nonalcoholic steatohepatitis. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102184. [PMID: 38665220 PMCID: PMC11044058 DOI: 10.1016/j.omtn.2024.102184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/28/2024]
Abstract
Nonalcoholic steatohepatitis (NASH) represents a severe disease subtype of nonalcoholic fatty liver disease (NAFLD) that is thought to be highly associated with systemic metabolic abnormalities. It is characterized by a series of substantial liver damage, including hepatocellular steatosis, inflammation, and fibrosis. The end stage of NASH, in some cases, may result in cirrhosis and hepatocellular carcinoma (HCC). Nowadays a large number of investigations are actively under way to test various therapeutic strategies, including emerging oligonucleotide drugs (e.g., antisense oligonucleotide, small interfering RNA, microRNA, mimic/inhibitor RNA, and small activating RNA) that have shown high potential in treating this fatal liver disease. This article systematically reviews the pathogenesis of NASH/NAFLD, the promising druggable targets proven by current studies in chemical compounds or biological drug development, and the feasibility and limitations of oligonucleotide-based therapeutic approaches under clinical or pre-clinical studies.
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Affiliation(s)
- Sixu Li
- Department of Pathophysiology, West China College of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610066, China
| | - Feng Xiong
- Department of Cardiology, The Third People’s Hospital of Chengdu, Chengdu 610031, China
| | - Songbo Zhang
- Department of Breast Surgery, Sichuan Clinical Research Center for Cancer, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliated Cancer Hospital of University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Jinghua Liu
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Li Weibo Institute for Rare Diseases Research, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Viral Vector Core, University of Massachusetts Chan Medical, School, Worcester, MA 01605, USA
| | - Jun Xie
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
- Viral Vector Core, University of Massachusetts Chan Medical, School, Worcester, MA 01605, USA
| | - Yi Wang
- Department of Pathophysiology, West China College of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610066, China
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ASGR1 and Its Enigmatic Relative, CLEC10A. Int J Mol Sci 2020; 21:ijms21144818. [PMID: 32650396 PMCID: PMC7404283 DOI: 10.3390/ijms21144818] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/03/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022] Open
Abstract
The large family of C-type lectin (CLEC) receptors comprises carbohydrate-binding proteins that require Ca2+ to bind a ligand. The prototypic receptor is the asialoglycoprotein receptor-1 (ASGR1, CLEC4H1) that is expressed primarily by hepatocytes. The early work on ASGR1, which is highly specific for N-acetylgalactosamine (GalNAc), established the foundation for understanding the overall function of CLEC receptors. Cells of the immune system generally express more than one CLEC receptor that serve diverse functions such as pathogen-recognition, initiation of cellular signaling, cellular adhesion, glycoprotein turnover, inflammation and immune responses. The receptor CLEC10A (C-type lectin domain family 10 member A, CD301; also called the macrophage galactose-type lectin, MGL) contains a carbohydrate-recognition domain (CRD) that is homologous to the CRD of ASGR1, and thus, is also specific for GalNAc. CLEC10A is most highly expressed on immature DCs, monocyte-derived DCs, and alternatively activated macrophages (subtype M2a) as well as oocytes and progenitor cells at several stages of embryonic development. This receptor is involved in initiation of TH1, TH2, and TH17 immune responses and induction of tolerance in naïve T cells. Ligand-mediated endocytosis of CLEC receptors initiates a Ca2+ signal that interestingly has different outcomes depending on ligand properties, concentration, and frequency of administration. This review summarizes studies that have been carried out on these receptors.
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Springer AD, Dowdy SF. GalNAc-siRNA Conjugates: Leading the Way for Delivery of RNAi Therapeutics. Nucleic Acid Ther 2018; 28:109-118. [PMID: 29792572 PMCID: PMC5994659 DOI: 10.1089/nat.2018.0736] [Citation(s) in RCA: 365] [Impact Index Per Article: 60.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 04/26/2018] [Indexed: 12/15/2022] Open
Abstract
Short-interfering RNA (siRNA)-induced RNAi responses have great potential to treat a wide variety of human diseases from cancer to pandemic viral outbreaks to Parkinson's Disease. However, before siRNAs can become drugs, they must overcome a billion years of evolutionary defenses designed to keep invading RNAs on the outside cells from getting to the inside of cells. Not surprisingly, significant effort has been placed in developing a wide array of delivery technologies. Foremost of these has been the development of N-acetylgalactosamine (GalNAc) siRNA conjugates for delivery to liver. Tris-GalNAc binds to the Asialoglycoprotein receptor that is highly expressed on hepatocytes resulting in rapid endocytosis. While the exact mechanism of escape across the endosomal lipid bilayer membrane remains unknown, sufficient amounts of siRNAs enter the cytoplasm to induce robust, target selective RNAi responses in vivo. Multiple GalNAc-siRNA conjugate clinical trials, including two phase III trials, are currently underway by three biotech companies to treat a wide variety of diseases. GalNAc-siRNA conjugates are a simple solution to the siRNA delivery problem for liver hepatocytes and have shown the RNAi (and antisense oligonucleotide) field the path forward for targeting other tissue types.
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Affiliation(s)
- Aaron D Springer
- Department of Cellular and Molecular Medicine, University of California San Diego , La Jolla, California
| | - Steven F Dowdy
- Department of Cellular and Molecular Medicine, University of California San Diego , La Jolla, California
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Verma SK, Modi A, Dravid A, Bellare J. Lactobionic acid-functionalized polyethersulfone hollow fiber membranes promote HepG2 attachment and function. RSC Adv 2018; 8:29078-29088. [PMID: 35539695 PMCID: PMC9084356 DOI: 10.1039/c8ra02282h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 08/07/2018] [Indexed: 01/29/2023] Open
Abstract
Surface modification of polyethersulfone hollow fibers, which are important in bio-artificial liver, is increasingly used to improve biocompatibility and promote the adhesion and proliferation of hepatocytes resulting in improved cell functionality. Hepatocytes are anchorage-dependent cells, and membrane surface modification enhances the hepatic cell adhesion and proliferation. Specific interaction of the asialoglycoprotein receptor on hepatocyte cell surfaces with a galactose moiety enhances the attachment of the cells on a biocompatible substrate. In this study, the outer surface of the polyethersulfone (P) hollow fiber membranes (HFMs) was chemically modified by covalent coupling with lactobionic acid (LBA). The energy dispersive X-ray spectrometry elemental mapping, attenuated total reflectance-Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy confirmed the LBA-coupling on the outer surface of P-LBA HFMs. Hemocompatibility study indicated the suitability of the modified membranes with human blood. These membranes showed remarkably improved biocompatibility with human primary mesenchymal stem cells and HepG2 cells. Characteristic multi-cellular spheroids of HepG2 cells were observed under scanning electron and confocal microscopy. HepG2 cell functional activity was measured by quantifying the urea synthesis, albumin secretion and glucose consumption in the culture media, which indicated the improved HepG2 functions. These experimental results clearly suggest the potentiality of these LBA-modified P HFMs as a suitable biocompatible substrate for promoting HepG2 attachment and function leading to their application in bioreactors and bio-artificial liver devices. Surface modification of polyethersulfone hollow fibers, which are important in bio-artificial liver, is increasingly used to improve biocompatibility and promote the adhesion and proliferation of hepatocytes resulting in improved cell functionality.![]()
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Affiliation(s)
- Surendra Kumar Verma
- Department of Chemical Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Akshay Modi
- Department of Chemical Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Ashwin Dravid
- Department of Chemical Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Jayesh Bellare
- Department of Chemical Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
- Centre for Research in Nanotechnology & Sciences
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Huang Y. Preclinical and Clinical Advances of GalNAc-Decorated Nucleic Acid Therapeutics. MOLECULAR THERAPY. NUCLEIC ACIDS 2017; 6:116-132. [PMID: 28325278 PMCID: PMC5363494 DOI: 10.1016/j.omtn.2016.12.003] [Citation(s) in RCA: 190] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 12/04/2016] [Accepted: 12/04/2016] [Indexed: 01/03/2023]
Abstract
A main challenge in realizing the full potential of nucleic acid therapeutics is efficient delivery of them into targeted tissues and cells. N-acetylgalactosamine (GalNAc) is a well-defined liver-targeted moiety benefiting from its high affinity with asialoglycoprotein receptor (ASGPR). By conjugating it directly to the oligonucleotides or decorating it to a certain delivery system as a targeting moiety, GalNAc has achieved compelling successes in the development of nucleic acid therapeutics in recent years. Several oligonucleotide modalities are undergoing pivotal clinical studies, followed by a blooming pipeline in the preclinical stage. This review covers the progress of GalNAc-decorated oligonucleotide drugs, including siRNAs, anti-miRs, and ASOs, which provides a panorama for this field.
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Affiliation(s)
- Yuanyu Huang
- Advanced Research Institute for Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China; Institute of Molecular Medicine, Peking University, Beijing 100871, China.
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6
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Monestier M, Charbonnier P, Gateau C, Cuillel M, Robert F, Lebrun C, Mintz E, Renaudet O, Delangle P. ASGPR-Mediated Uptake of Multivalent Glycoconjugates for Drug Delivery in Hepatocytes. Chembiochem 2016; 17:590-4. [DOI: 10.1002/cbic.201600023] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Marie Monestier
- Université Grenoble Alpes; INAC-SCIB; CEA; INAC-SCIB; 17 rue des martyrs 38054 Grenoble cedex 09 France
- Université Grenoble Alpes; DCM; CNRS; DCM; 570 rue de la chimie 38041 Grenoble cedex 09 France
| | - Peggy Charbonnier
- Université Grenoble Alpes; iRTSV-LCBM; CEA; iRTSV-LCBM; CNRS; iRTSV-LCBM; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Christelle Gateau
- Université Grenoble Alpes; INAC-SCIB; CEA; INAC-SCIB; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Martine Cuillel
- Université Grenoble Alpes; iRTSV-LCBM; CEA; iRTSV-LCBM; CNRS; iRTSV-LCBM; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Faustine Robert
- Université Grenoble Alpes; INAC-SCIB; CEA; INAC-SCIB; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Colette Lebrun
- Université Grenoble Alpes; INAC-SCIB; CEA; INAC-SCIB; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Elisabeth Mintz
- Université Grenoble Alpes; iRTSV-LCBM; CEA; iRTSV-LCBM; CNRS; iRTSV-LCBM; 17 rue des martyrs 38054 Grenoble cedex 09 France
| | - Olivier Renaudet
- Université Grenoble Alpes; DCM; CNRS; DCM; 570 rue de la chimie 38041 Grenoble cedex 09 France
- Institut Universitaire de France; 103 boulevard Saint-Michel 75005 Paris France
| | - Pascale Delangle
- Université Grenoble Alpes; INAC-SCIB; CEA; INAC-SCIB; 17 rue des martyrs 38054 Grenoble cedex 09 France
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Tian X, Baek KH, Shin I. Dual-labeled glycoclusters: synthesis and their application in monitoring lectin-mediated endocytosis. MOLECULAR BIOSYSTEMS 2013; 9:978-86. [DOI: 10.1039/c3mb25491g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Dorasamy S, Narainpersad N, Singh M, Ariatti M. Novel targeted liposomes deliver sirna to hepatocellular carcinoma cells in vitro. Chem Biol Drug Des 2012; 80:647-56. [PMID: 22783887 DOI: 10.1111/j.1747-0285.2012.01446.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Liposomes form a major class of non-viral vectors for short interfering RNA delivery, however tissue and cell-specific targeting are additional requirements in the design of short interfering RNA delivery systems with a therapeutic potential. Selective delivery of liposomes to hepatocytes may be achieved by directing complexes to the asialoglycoprotein receptor, which is expressed on hepatocytes, and which displays high affinity for the β-d-galactopyranosyl moiety. We aimed to show that the d-galactopyranosyl ring in direct β-glycosidic link to cholesterol, when formulated into liposomes with 3β[N-(N',N'-dimethylaminopropane) carbamoyl] cholesterol (Chol-T) or its quaternary trimethylammonium analogue (Chol-Q), may promote targeted delivery of cytotoxic short interfering RNA to the human hepatoma cell line HepG2 via the asialoglycoprotein receptor. Liposome-short interfering RNA interactions were characterized by electron microscopy, dye displacement, gel retardation and nuclease assays. Stable short interfering RNA-protective lipoplexes were formed at N/P ratios in the range 5:1-7:1. Targeted lipoplex 4 achieved high transfection efficiencies at 50 nm short interfering RNA (70%) and <10% in a competition assay, whilst untargeted complexes reached low levels at the same concentration (<25%). Transfection efficiencies of all lipoplexes in the asialoglycoprotein receptor-negative cell line HEK293 under the same conditions were low. Lipoplexes containing cholesteryl-β-d-galactopyranoside may therefore form the basis for the development of useful hepatotropic short interfering RNA delivery vectors.
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Affiliation(s)
- Shantal Dorasamy
- Non-viral Gene Delivery Laboratory, Discipline of Biochemistry, University of KwaZulu-Natal, Westville campus, P. Bag X54001, Durban 4000, South Africa
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9
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Sørensen ALT, Clausen H, Wandall HH. Carbohydrate clearance receptors in transfusion medicine. Biochim Biophys Acta Gen Subj 2012; 1820:1797-808. [PMID: 22846227 DOI: 10.1016/j.bbagen.2012.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 07/10/2012] [Accepted: 07/20/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Complex carbohydrates play important functions for circulation of proteins and cells. They provide protective shields and refraction from non-specific interactions with negative charges from sialic acids to enhance circulatory half-life. For recombinant protein therapeutics carbohydrates are especially important to enhance size and reduce glomerular filtration loss. Carbohydrates are, however, also ligands for a large number of carbohydrate-binding lectins exposed to the circulatory system that serve as scavenger receptors for the innate immune system, or have more specific roles in targeting of glycoproteins and cells. SCOPE OF REVIEW Here we provide an overview of the common lectin receptors that play roles for circulating glycoproteins and cells, and present a discussion of ways to engineer glycosylation of recombinant biologics and cells to improve therapeutic effects. MAJOR CONCLUSIONS While the pharmaceutical industry has learned how to exploit carbohydrates to improve pharmacokinetic properties of recombinant therapeutics, our understanding of how to improve cell-based therapies by manipulation of complex carbohydrates is still at its infancy. Progress with the latter has recently been achieved with cold-stored platelets, where exposure of uncapped glycans lead to rapid clearance from circulation by several lectin-mediated pathways. GENERAL SIGNIFICANCE Understanding lectin-mediated clearance pathways is essential for progress in development of biological pharmaceuticals.
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10
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Symens N, Méndez-Ardoy A, Díaz-Moscoso A, Sánchez-Fernández E, Remaut K, Demeester J, Fernández JMG, De Smedt SC, Rejman J. Efficient Transfection of Hepatocytes Mediated by mRNA Complexed to Galactosylated Cyclodextrins. Bioconjug Chem 2012; 23:1276-89. [DOI: 10.1021/bc3001003] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Nathalie Symens
- Laboratory
of General Biochemistry
and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Alejandro Méndez-Ardoy
- Departamento de Química
Organica, Universidad de Sevilla, c/ Profesor Garcia Gonzalez 1, E-41012 Sevilla, Spain
| | - Alejandro Díaz-Moscoso
- Instituto de Investigaciones Químicas (IIQ), CSIC-Universidad de Sevilla, Américo 49, Isla
de Cartuja, E-41092 Sevilla, Spain
| | - Elena Sánchez-Fernández
- Instituto de Investigaciones Químicas (IIQ), CSIC-Universidad de Sevilla, Américo 49, Isla
de Cartuja, E-41092 Sevilla, Spain
| | - Katrien Remaut
- Laboratory
of General Biochemistry
and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Joseph Demeester
- Laboratory
of General Biochemistry
and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - José M. García Fernández
- Instituto de Investigaciones Químicas (IIQ), CSIC-Universidad de Sevilla, Américo 49, Isla
de Cartuja, E-41092 Sevilla, Spain
| | - Stefaan C. De Smedt
- Laboratory
of General Biochemistry
and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | - Joanna Rejman
- Laboratory
of General Biochemistry
and Physical Pharmacy, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
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Cho C, Hoshiba T, Harada I, Akaike T. Regulation of hepatocyte behaviors by galactose-carrying polymers through receptor-mediated mechanism. REACT FUNCT POLYM 2007. [DOI: 10.1016/j.reactfunctpolym.2007.07.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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12
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Hynes MA, Buck LB, Gitt M, Barondes S, Dodd J, Jessell TM. Carbohydrate recognition in neuronal development: structure and expression of surface oligosaccharides and beta-galactoside-binding lectins. CIBA FOUNDATION SYMPOSIUM 2007; 145:189-210; discussion 210-8. [PMID: 2791751 DOI: 10.1002/9780470513828.ch12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The differentiation and development of vertebrate neurons is controlled in part by interactions with cell surface and extracellular matrix molecules, many of which are glycoproteins that mediate their developmental actions by homophilic or heterophilic binding to other glycoproteins. In addition there is increasing evidence that cell recognition and adhesion in some embryonic cell types involve interactions between cell surface oligosaccharides and complementary carbohydrate-binding proteins. Although a role for carbohydrate recognition in neuronal development has been proposed, the precise function of complex carbohydrate structures on neural cells has not been defined. To approach this problem, we have examined the structure and expression of cell surface oligosaccharides and carbohydrate-binding proteins by primary sensory neurons in the rat dorsal root ganglion (DRG). There are several functionally distinct subsets of DRG neurons, each of which conveys a different sensory modality to distinct target domains in the spinal cord. Monoclonal antibodies against defined oligosaccharide structures identify each of the major subsets of DRG neurons on the basis of their expression of a distinct set of complex oligosaccharides, derived from lacto-, globo- and ganglioseries backbone structures. In particular, small diameter DRG neurons involved in pain processing express beta-galactoside-based lactoseries oligosaccharides. DRG and spinal cord neurons also express two soluble beta-galactoside-binding proteins of relative molecular masses 14,500 and 29,000, termed RL-14.5 and RL-29, which represent potential ligands for lactoseries oligosaccharides. RL-14.5 is expressed by the majority of DRG neurons whereas RL-29 is restricted to the subset of small DRG neurons that express surface N-acetyllactosamine structures. RL-14.5 and RL-29 are expressed soon after the differentiation of DRG neurons and appear to be released from cultured DRG neurons. Rat brain cDNA clones encoding RL-14.5 have been isolated. The nucleotide and predicted amino acid sequence of RL-14.5 has confirmed that this lectin is highly homologous to soluble beta-galactoside-binding proteins in other vertebrate species. Northern blot analysis and in situ hybridization indicate that RL-14.5 mRNA is selectively expressed in sensory and motor neurons in the rat nervous system. The selective expression of lactoseries oligosaccharides and complementary beta-galactoside-binding lectins may contribute to the differentiation and/or development of these two classes of neurons.
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Affiliation(s)
- M A Hynes
- Center for Neurobiology and Behavior, Columbia University, College of Physicians and Surgeons, New York, NY 10032
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13
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Rozema DB, Lewis DL, Wakefield DH, Wong SC, Klein JJ, Roesch PL, Bertin SL, Reppen TW, Chu Q, Blokhin AV, Hagstrom JE, Wolff JA. Dynamic PolyConjugates for targeted in vivo delivery of siRNA to hepatocytes. Proc Natl Acad Sci U S A 2007; 104:12982-7. [PMID: 17652171 PMCID: PMC1941806 DOI: 10.1073/pnas.0703778104] [Citation(s) in RCA: 508] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Achieving efficient in vivo delivery of siRNA to the appropriate target cell would be a major advance in the use of RNAi in gene function studies and as a therapeutic modality. Hepatocytes, the key parenchymal cells of the liver, are a particularly attractive target cell type for siRNA delivery given their central role in several infectious and metabolic disorders. We have developed a vehicle for the delivery of siRNA to hepatocytes both in vitro and in vivo, which we have named siRNA Dynamic PolyConjugates. Key features of the Dynamic PolyConjugate technology include a membrane-active polymer, the ability to reversibly mask the activity of this polymer until it reaches the acidic environment of endosomes, and the ability to target this modified polymer and its siRNA cargo specifically to hepatocytes in vivo after simple, low-pressure i.v. injection. Using this delivery technology, we demonstrate effective knockdown of two endogenous genes in mouse liver: apolipoprotein B (apoB) and peroxisome proliferator-activated receptor alpha (ppara). Knockdown of apoB resulted in clear phenotypic changes that included a significant reduction in serum cholesterol and increased fat accumulation in the liver, consistent with the known functions of apoB. Knockdown of ppara also resulted in a phenotype consistent with its known function, although with less penetrance than observed in apoB knockdown mice. Analyses of serum liver enzyme and cytokine levels in treated mice indicated that the siRNA Dynamic PolyConjugate was nontoxic and well tolerated.
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Affiliation(s)
- David B. Rozema
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
- To whom correspondence may be addressed. E-mail: or
| | - David L. Lewis
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
- To whom correspondence may be addressed. E-mail: or
| | | | - So C. Wong
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
| | - Jason J. Klein
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
| | - Paula L. Roesch
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
| | | | - Tom W. Reppen
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
| | - Qili Chu
- *Mirus Bio Corporation, 505 South Rosa Road, Madison, WI 53719; and
| | | | | | - Jon A. Wolff
- Departments of Pediatrics and Medical Genetics, Waisman Center, University of Wisconsin, 1500 Highland Avenue, Madison, WI 53719
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Rice KG, Lee YC. Oligosaccharide valency and conformation in determining binding to the asialoglycoprotein receptor of rat hepatocytes. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 66:41-83. [PMID: 8430516 DOI: 10.1002/9780470123126.ch2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- K G Rice
- Department of Pharmaceutics and Pharmaceutical Chemistry, Ohio State University, Columbus
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15
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Terada T, Nishikawa M, Yamashita F, Hashida M. Analysis of the molecular interaction of glycosylated proteins with rabbit liver asialoglycoprotein receptors using surface plasmon resonance spectroscopy. J Pharm Biomed Anal 2006; 41:966-72. [PMID: 16546339 DOI: 10.1016/j.jpba.2006.01.054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 01/24/2006] [Accepted: 01/28/2006] [Indexed: 11/20/2022]
Abstract
A sensitive, accurate, and efficient biosensor analysis using surface plasmon resonance (SPR) spectroscopy was used for delineating the molecular interaction between rabbit liver asialoglycoprotein receptors (ASGPR) and glycosylated proteins. Isolated rabbit liver ASGPR obtained by affinity column chromatography was dissolved in buffer solution containing TritonX-100 and immobilized on the SPR sensor chip by amine coupling. The SPR study demonstrated that the association rate constants (ka) of galactosylated proteins with ASGPR are dependent on the number of galactose residues, while the dissociation rate constants (kd) are influenced not only by the surface density of the galactose moieties but also by their steric configuration. In addition, it was demonstrated that D-fucosylated BSA had a higher binding affinity to ASGPR than Gal-BSA, when the degree of sugar modification was equivalent.
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Affiliation(s)
- Takeshi Terada
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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16
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Cho CS, Seo SJ, Park IK, Kim SH, Kim TH, Hoshiba T, Harada I, Akaike T. Galactose-carrying polymers as extracellular matrices for liver tissue engineering. Biomaterials 2006; 27:576-85. [PMID: 16084586 DOI: 10.1016/j.biomaterials.2005.06.008] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2005] [Accepted: 06/20/2005] [Indexed: 11/29/2022]
Abstract
Extracellular matrix (ECM) plays important roles in tissue engineering because cellular growth and differentiation, in the two-dimensional cell culture as well as in the three-dimensional space of the developing organism, require ECM with which the cells can interact. Especially, the bioartificial liver-assist device or regeneration of the liver-tissue substitutes for liver tissue engineering requires a suitable ECM for hepatocyte culture because hepatocytes are anchorage-dependent cells and are highly sensitive to the ECM milieu for the maintenance of their viability and differentiated functions. Galactose-carrying synthetic ECMs derived from synthetic polymers and natural polymers bind hepatocytes through a receptor-mediated mechanism, resulting in enhanced hepatocyte functions. Attachment and functions of hepatocytes were affected by physico-chemical properties including ECM geometry as well as the type, density and orientation of galactose. Also, cellular environment, medium composition and dynamic culture system influenced liver-specific functions of hepatocytes beside ECM.
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Affiliation(s)
- C S Cho
- School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, South Korea
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17
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Shimojo S, Cho CS, Park IK, Kunou M, Goto M, Akaike T. Helical structure of sugar-carrying polystyrene in aqueous solution by circular dichroism. Carbohydr Res 2003; 338:2129-33. [PMID: 14505881 DOI: 10.1016/s0008-6215(03)00343-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Radical polymerization of N-p-vinylbenzyl-D-lactonamide (VLA) gave an optically active helical polymer. The stereoregularity of poly(N-p-vinylbenzyl-D-lactonamide) (PVLA) measured by 13C NMR spectroscopy showed a well-resolved sharp-line width, which was assigned to the phenyl C-1 carbon of the isotactic polystyrene (PS). The helical structure of PVLA shown by circular dichroism (CD) indicated that the aromatic groups were chirally supramolecular-packed giving optically active disaccharide units in the side chain covalently linked via an amide linkage with PS, the original PS not being optically active. The intensity of CD for PVLA (a) decreased with increasing temperature due to the change in the conformation of the phenyl group or to the breakdown of intermolecular hydrogen bonding of amide groups and (b) increased in a mixture of water and alcohol due to the increased hydrophobicity. The CD intensity for maltose-carrying PS (PVMA) was slightly higher than that of PVLA CD due to the more hydrophobic property of PVMA than PVLA.
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Affiliation(s)
- Shojiro Shimojo
- Department of Biomolecular Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho Midori-ku, Yokohama 226-8501, Japan
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18
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Kolatkar AR, Leung AK, Isecke R, Brossmer R, Drickamer K, Weis WI. Mechanism of N-acetylgalactosamine binding to a C-type animal lectin carbohydrate-recognition domain. J Biol Chem 1998; 273:19502-8. [PMID: 9677372 DOI: 10.1074/jbc.273.31.19502] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mammalian hepatic asialoglycoprotein receptor, a member of the C-type animal lectin family, displays preferential binding to N-acetylgalactosamine compared with galactose. The structural basis for selective binding to N-acetylgalactosamine has been investigated. Regions of the carbohydrate-recognition domain of the receptor believed to be important in preferential binding to N-acetylgalactosamine have been inserted into the homologous carbohydrate-recognition domain of a mannose-binding protein mutant that was previously altered to bind galactose. Introduction of a single histidine residue corresponding to residue 256 of the hepatic asialoglycoprotein receptor was found to cause a 14-fold increase in the relative affinity for N-acetylgalactosamine compared with galactose. The relative ability of various acyl derivatives of galactosamine to compete for binding to this modified carbohydrate-recognition domain suggest that it is a good model for the natural N-acetylgalactosamine binding site of the asialoglycoprotein receptor. Crystallographic analysis of this mutant carbohydrate-recognition domain in complex with N-acetylgalactosamine reveals a direct interaction between the inserted histidine residue and the methyl group of the N-acetyl substituent of the sugar. Evidence for the role of the side chain at position 208 of the receptor in positioning this key histidine residue was obtained from structural analysis and mutagenesis experiments. The corresponding serine residue in the modified carbohydrate-recognition domain of mannose-binding protein forms a hydrogen bond to the imidazole side chain. When this serine residue is changed to valine, loss in selectivity for N-acetylgalactosamine is observed. The structure of this mutant reveals that the beta-branched valine side chain interacts directly with the histidine side chain, resulting in an altered imidazole ring orientation.
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Affiliation(s)
- A R Kolatkar
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305, USA
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19
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Abstract
Sialic acids (Sias) are terminal components of many glycoproteins and glycolipids especially of higher animals. In this exposed position they contribute significantly to the structural properties of these molecules, both in solution and on cell surfaces. Therefore, it is not surprising that Sias are important regulators of cellular and molecular interactions, in which they play a dual role. They can either mask recognition sites or serve as recognition determinants. Whereas the role of Sias in masking and in binding of pathogens to host cells has been documented over many years, their role in nonpathological cellular interaction has only been shown recently. The aim of this chapter is to summarize our knowledge about Sias in masking, for example, galactose residues, and to review the progress made during the past few years with respect to Sias as recognition determinants in the adhesion of pathogenic viruses, bacteria, and protozoa, and particularly as binding sites for endogenous cellular interaction molecules. Finally, perspectives for future research on these topics are discussed.
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Affiliation(s)
- S Kelm
- Biochemisches Institut, University of Kiel, Germany
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20
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Iobst ST, Drickamer K. Selective sugar binding to the carbohydrate recognition domains of the rat hepatic and macrophage asialoglycoprotein receptors. J Biol Chem 1996; 271:6686-93. [PMID: 8636087 DOI: 10.1074/jbc.271.12.6686] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Asialoglycoprotein receptors on the surfaces of both hepatocytes and peritoneal macrophages bind terminal galactose residues of desialylated glycoproteins and mediate endocytosis and eventual degradation of these ligands. The hepatic receptor binds oligosaccharides with terminal N-acetylgalactosamine residues more tightly than ligands with terminal galactose residues, but the macrophage receptor shows no such differential binding affinity. Carbohydrate recognition domains from the macrophage receptor and the major subunit of the hepatic receptor have been expressed in a bacterial system and have been shown to retain the distinct binding selectivities of the receptors from which they derive. Binding of a series of N-acyl derivatives of galactosamine suggests that the 2-substituent of these sugars interacts with the surface of the hepatic receptor with highest affinity binding observed for the N-propionyl derivative. Chimeric sugar-binding domains have been used to identify three regions of the hepatic receptor that are essential for establishing selectivity for N-acetylgalactosamine over galactose. Based on these results and the orientation of N-acetylgalactosamine when bound to an homologous galactose-binding mutant of rat serum mannose-binding protein, a fourth region likely to interact with N-acetylgalactosamine has been identified and probed by site-directed mutagenesis. The results of these studies define a binding pocket for the 2-substituent of N-acetylgalactosamine in the hepatic asialoglycoprotein receptor.
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Affiliation(s)
- S T Iobst
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA
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21
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Sarkar HS, Sen AK, Mukherjee M, Banerji N, Banerjee S. Syntheses of several 99mTc and 131I labeled neoglycoalbumins and their differential uptake patterns in animal biodistribution experiments. Nucl Med Biol 1995; 22:589-97. [PMID: 7581168 DOI: 10.1016/0969-8051(95)00003-g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Several glycoconjugates, alpha-D-mannopyranosyl, beta-L-fucopyranosyl, alpha-L-rhamnopyranosyl, beta-D-glucopyranosyl and beta-D-galactopyranosyl human serum albumin, were synthesized using C9-tether and radiolabeled with 99mTc and 131I. Both 99mTc and 131I radiolabeled neoglycoalbumins had considerable stability and exhibited similar biodistribution patterns within the experimental limits. The results of biodistribution studies can be explained from the in vitro observations that 99mTc-beta-D-galactopyranosyl albumin binds to hepatic binding protein in liver in a dose-dependent fashion. The radiolabeled glycoalbumins derived from D-mannopyranose and L-fucopyranose also bind in a dose-dependent fashion to the receptors present in the liver sinusoidal cells and spleen macrophages. The beta-D-glucopyranosyl and alpha-L-rhamnopyranosyl neoglycoalbumins accumulate nonspecifically in liver and spleen.
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Affiliation(s)
- H S Sarkar
- Indian Institute of Chemical Biology, Department of Nuclear Medicine, Jadavpur, Calcutta
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22
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Adler P, Wood SJ, Lee YC, Lee RT, Petri WA, Schnaar RL. High affinity binding of the Entamoeba histolytica lectin to polyvalent N-acetylgalactosaminides. J Biol Chem 1995; 270:5164-71. [PMID: 7890626 DOI: 10.1074/jbc.270.10.5164] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Entamoeba histolytica trophozoites initiate pathogenic colonization by adherence to host glycoconjugates via an amebic surface lectin which binds to galactose (Gal) and N-acetylgalactosamine (GalNAc) residues. Monovalent and multivalent carbohydrate ligands were screened for inhibition of E. histolytica lectin-mediated human red cell hemagglutination, revealing that: (i) the synthetic multivalent neoglycoprotein GalNAc39BSA (having an average of 39 GalNAc residues linked to bovine serum albumin) was 140,000-fold more potent an inhibitor than monovalent GalNAc and 500,000-fold more potent than monovalent Gal; and (ii) small synthetic multivalent ligands which bind with high affinity to the mammalian hepatic Gal/GalNAc lectin do not bind with high affinity to the E. histolytica lectin. Radioligand binding studies revealed saturable binding of 125I-GalNAc39BSA to E. histolytica membranes (KD = 10 +/- 3 nM, Bmax = 0.9 +/- 0.08 pmol/mg membrane protein). Maximal binding required the presence of calcium chloride (300 microM) or sodium chloride (50 mM), and had a broad pH maximum (pH 6-9). GalNAc39BSA was 200,000-fold more potent than monovalent GalNAc in blocking radio-ligand binding. Among synthetic saccharide-derivatized linear polymers, the GalNAc beta and GalNAc alpha 3Gal beta derivatives were the most potent, with GalNAc alpha and GalNAc alpha 3(Fuc alpha 2)Gal beta derivatives much weaker. The data support a model in which a unique pattern of spaced multiple GalNAc residues are the highest affinity targets for the E. histolytica lectin.
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Affiliation(s)
- P Adler
- Department of Pharmacology and Molecular Science, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
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23
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24
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Krebs A, Depew WT, Szarek WA, Hay GW, Hronowski LJ. Binding of D-galactose-terminated ligands to rabbit asialoglycoprotein receptor. Carbohydr Res 1994; 254:257-68. [PMID: 8180988 DOI: 10.1016/0008-6215(94)84258-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The binding affinities of a series of D-galactose-terminated glycerol glycosides and oligosaccharides for the asialoglycoprotein receptor isolated from rabbit liver were determined in vitro using a radioreceptor-inhibition assay with 125I-asialoorosomucoid. The relative affinities of the synthetic ligands increased with the number of exposed D-galactose termini. Of the compounds examined, 1,2,3-tri-O-beta-lactosylglycerol associated with the greatest affinity (estimated Kd = 7.97 x 10(-5) M). Examination of the affinities of the synthetic series indicated that both the number and propinquity of the D-galactose termini influenced the strength of the binding interactions.
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Affiliation(s)
- A Krebs
- Department of Medicine, Queen's University, Kingston, Ontario, Canada
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25
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Sharma SK, Bagshawe KD, Burke PJ, Boden JA, Rogers GT, Springer CJ, Melton RG, Sherwood RF. Galactosylated antibodies and antibody-enzyme conjugates in antibody-directed enzyme prodrug therapy. Cancer 1994; 73:1114-20. [PMID: 8306255 DOI: 10.1002/1097-0142(19940201)73:3+<1114::aid-cncr2820731352>3.0.co;2-l] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Antibody directed enzyme prodrug therapy (ADEPT) has been studied as a two- and three-phase system in which an antibody to a tumor-associated antigen has been used to deliver an enzyme to tumor sites where it can convert a relatively nontoxic prodrug to a cytotoxic agent. In such a system, it is necessary to allow the enzyme activity to clear from the blood before prodrug injection to avoid toxicity caused by prodrug activation in plasma. To accelerate plasma clearance of enzyme activity, two approaches have been studied. The studies have been performed with a monoclonal anticarcinoembryonic-antigen antibody fragment A5B7-F(ab')2 conjugated to a bacterial enzyme, carboxypeptidase G2 (CPG2), in LS174T xenografted mice. In the first approach, a monoclonal antibody (SB43), directed at CPG2, was used, which inactivates CPG2 in vitro and in vivo. SB43 was galactosylated so that it had sufficient time to form a complex with plasma CPG2, resulting in the inactivation and clearance of the complex from plasma via the carbohydrate-specific receptors in the liver. Injection of SB43gal 19 hours after administration of the radiolabeled conjugate reduced the percentage of injected dose per gram in blood without affecting levels in the tumor. The second approach involved galactosylation of the conjugate so that it cleared rapidly from blood via the asialoglycoprotein receptors in the liver. Localization of the radiolabeled conjugate was achieved by blocking this receptor for about 8 hours with a single injection (8 mg/mouse) of an inhibitor that binds competitively to the receptor. This allowed tumor localization of the conjugate followed by a rapid clearance of the galactosylated conjugate from blood as the inhibitor was consumed. A tumor-to-blood ratio of 45:1 was obtained at 24 hours, which increased to 100:1 at 72 hours after the conjugate injection. These accelerated clearance mechanisms have been applied in antitumor studies in ADEPT.
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Affiliation(s)
- S K Sharma
- Department of Medical Oncology, Charing Cross Hospital, London, United Kingdom
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26
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Qi P, Sykes TR, Koganty RR, Selvaraj S, Noujaim AA. Preparation and biological evaluation of radiolabelled antibodies with selected carbohydrate modifications. Nucl Med Biol 1993; 20:453-9. [PMID: 8504287 DOI: 10.1016/0969-8051(93)90076-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Two carbohydrates, N-acetylgalactosamine (GalNAc) and galactose-beta-1,3-GalNAc have been attached to human IgG (hIgG) by a novel linking reagent, hexafluoroglutaric acid dimethyl ester. Fluorine-19 NMR signals were used for the determination of the conjugation ratio. A third carbohydrate, sialic acid, was conjugated via reductive amination and the conjugation ratio determined by a resorcinol assay. The biological behaviour of these radioiodinated antibodies with carbohydrate modifications in normal mice indicates an enhanced liver uptake at 15 min post-injection with an associated change in circulating blood levels occurs for the galactose-based hIgG preparations. However, no significant differences in the biodistribution were observed for the sialic acid conjugate. These studies confirm the potential of carbohydrate-antibody conjugation for modifying the behaviour of antibodies in immunoscintigraphy and radioimmunotherapy.
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Affiliation(s)
- P Qi
- Faculty of Pharmacy, University of Alberta, Edmonton, Canada
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27
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Tanzer ML, Chandrasekaran S, Dean JW, Giniger MS. Role of laminin carbohydrates on cellular interactions. Kidney Int 1993; 43:66-72. [PMID: 8433571 DOI: 10.1038/ki.1993.12] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Laminins, a family of large multidomain glycoproteins of the basal lamina, have been implicated in the development and maintenance of cellular and tissue organization. Considerable interest has arisen concerning the ways in which laminin carries out its biological functions. Previously these biologic responses have been primarily attributed to the peptide sequences of laminin, however, newer studies suggest that laminin carbohydrates may also participate in such cellular activities. Recently, a subpopulation of laminin molecules purified from EHS sarcoma by lectin affinity chromatography has been shown to contain about 25 to 30% carbohydrate. Most of the carbohydrates present are complex-type asparagine-linked oligosaccharides encompassing many different structures, some of which are unique to laminin. To date, the biological function of the carbohydrates of laminin remains somewhat unclear. They do not appear to be needed for heparin binding or to enhance proteinase stability, however, current evidence suggests they are important in cellular spreading and neurite outgrowth. It is our hypothesis that in the covalently-linked carbohydrate moieties of laminin will ultimately prove to be involved in information transfer to responsive cells. It is the purpose of this review to delineate current concepts of the structure and function of this unique glycoprotein's sugar chains.
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Affiliation(s)
- M L Tanzer
- Department of BioStructure and Function, University of Connecticut Health Center, Farmington
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28
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Eichler HG, Menear KA, Dunnet KE, Hastewell JG, Taylor PW. Studies on the uptake of low molecular weight monomeric tris-galactosyl conjugates by the rat liver. Biochem Pharmacol 1992; 44:2117-22. [PMID: 1472076 DOI: 10.1016/0006-2952(92)90337-i] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have attempted to direct low molecular weight compounds to the liver via the internalizing asialoglycoprotein receptor on parenchymal cells by conjugation to a monomeric triantennary galactosyl cluster. Acetate and a hypolipidaemic ansamycin were derivatized and the biodistribution of the conjugates was determined 250 sec and 30 min after administration to Wistar rats. The ansamycin conjugate (CGH46) was rapidly cleared from the circulation by the liver; after 250 sec, 64% of the radiolabelled dose was found in the liver compared to 18% in the blood. However, the distribution of the conjugate did not differ significantly from that of unconjugated ansamycin (CGH45). Tris-galactosyl acetate showed no capacity to localize in the liver, with only 2% recovered from that organ 250 sec after administration compared to 38% in the blood and 13-18% in the kidneys, skin and muscle. Extraction efficiency of CGH46 by isolated perfused rat livers was almost 20% of the administered dose and this value was not significantly changed by co-administration of specific inhibitors of the uptake process. It is concluded that derivatization of low molecular weight molecules with monomeric triantennary galactosyl residues is unlikely to increase their affinity for the liver.
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Affiliation(s)
- H G Eichler
- Research and Preclinical Development, CIBA-Geigy Pharmaceuticals, Horsham, West Sussex, U.K
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29
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Chandrasekaran S, Dean JW, Giniger MS, Tanzer ML. Laminin carbohydrates are implicated in cell signaling. J Cell Biochem 1991; 46:115-24. [PMID: 1918177 DOI: 10.1002/jcb.240460205] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have examined how laminin carbohydrates participate in cellular responses and have focused upon cell spreading and neurite outgrowth. Our earlier studies showed that unglycosylated laminin fully supported cell adhesion but did not promote subsequent spreading of mouse melanoma cells or neurite outgrowth of rat pheochromocytoma cells (Dean et al. (1990): J Biol Chem 265:12553-12562). In the present experiments, we determined whether those cellular responses could be restored to adherent cells. When a mixture of unglycosylated and glycosylated laminins was used as a substratum for mouse melanoma cells, some cells began to spread when 30% glycosylated laminin was present. At least 65% glycosylated laminin was required to elicit a maximal spreading response by the majority of the cells. In separate experiments, we found that cell spreading was fully restored by a pronase digest of glycosylated laminin; a similar digest of unglycosylated laminin had no effect. These results indicate that laminin carbohydrates, rather than polypeptide sequences, were responsible for cell spreading. We also conclude that substrate attachment of the carbohydrate moieties was not essential. In other experiments, laminins containing immature oligosaccharides were produced using two glycosylation pathway inhibitors, swainsonine or castanospermine. When such laminins were used to study cell spreading or neurite outgrowth, laminin containing immature oligosaccharides was as effective as laminin which contains fully processed oligosaccharides. In contrast, laminin with partially processed oligosaccharides had incomplete activity. These composite reconstitution experiments show that laminin carbohydrates provide essential information to responsive cells, enabling them to progress from an adherent state to a spread form or to extend neurite processes.
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Affiliation(s)
- S Chandrasekaran
- Department of BioStructure & Function, School of Dental Medicine, University of Connecticut Health Center, Farmington 06030
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30
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Ichikawa Y, Lee RT, Lee YC. Synthesis and Binding Activity of 3- and 4-Deoxy-N-Acetyl-Galactosamine Derivatives. J Carbohydr Chem 1990. [DOI: 10.1080/07328309008543865] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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31
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Lee RT, Rice KG, Rao NB, Ichikawa Y, Barthel T, Piskarev V, Lee YC. Binding characteristics of N-acetylglucosamine-specific lectin of the isolated chicken hepatocytes: similarities to mammalian hepatic galactose/N-acetylgalactosamine-specific lectin. Biochemistry 1989; 28:8351-8. [PMID: 2605188 DOI: 10.1021/bi00447a013] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Binding characteristics of N-acetylglucosamine- (GlcNAc) specific lectin on the chicken hepatocyte surface were probed by an inhibition assay using various sugars and glycosides as inhibitors. Results indicated that the binding area of the lectin is small, interacting only with GlcNAc residues whose 3- and 4-OH's are open. The combining site is probably of trough-type, since substitution with as large a group as monosaccharide is permitted on the C-6 side of GlcNAc, and on the C-1 side, the aglycon of GlcNAc can be very large (e.g., a glycoprotein). These binding characteristics are shared with the homologous mammalian lectin specific for galactose/N-acetylgalactosamine, suggesting that tertiary structure of the combining area of these two lectins is similar. This is understandable, since there is approximately 40% amino acid sequence identity in the carbohydrate recognition domain of these two lectins [Drickamer, K., Mannon, J. F., Binns, G., & Leung, J. O. (1984) J. Biol. Chem. 259, 770-778]. A series of glycosides, each containing two GlcNAc residues separated by different distances (from 0.8 to 4.7 nm), were synthesized. Inhibition assay with these and other cluster glycosides indicated that clustering of two or more GlcNAc residues increased the affinity toward the chicken lectin tremendously. Among the ligands containing two GlcNAc residues, the structure which allows a maximal inter-GlcNAc distance of 3.3 nm had the strongest affinity, its affinity increase over GlcNAc (monosaccharide) amounting to 100-fold. Longer distances slightly diminished the affinity, while shortening the distance caused substantial decrease in the affinity.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R T Lee
- Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218
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32
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Lee H, Kelm S, Yoshino T, Schauer R. Carbohydrate specificity of the galactose-recognizing receptor of rat peritoneal macrophages. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1988; 369:705-14. [PMID: 2850818 DOI: 10.1515/bchm3.1988.369.2.705] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The galactose-recognizing system of rat peritoneal macrophages mediates the binding and uptake of desialylated blood cells and glycoproteins. To characterize the specificity of this receptor, binding studies were performed with various galactose derivatives as competitive inhibitors and sialidase-treated erythrocytes or asialoorosomucoid as ligands for receptors, which were either membrane-bound or isolated after solubilization. From the results obtained it can be concluded that galactose is recognized via its hydrophobic and/or hydrophilic regions, formed by the accumulation of OH-functions on one side and of H-atoms on the other ("side effect"), whereas the binding partner or the anomeric configuration of galactose has no significant influence. Although it became apparent that not a single hydroxyl group of the sugar is responsible for binding, the hydroxyl at C-4 seems to be most important, followed by the OH-group at C-3. Those at C-1, C-2 and C-6 do not play a great role. This order of importance ("position effect") was found with galactose, derivatized by methylation or otherwise, and with diastereomers of galactose. Whereas the recognition of a single galactose residue leads to weak binding only, an appropriate arrangement of several of these ligands in one molecule results in an enormous increase in the binding strength of each galactose residue. This "cluster effect" was observed not only with membrane-bound but also with solubilized receptor. However, the binding of asialoorosomucoid by the latter was better inhibited with free galactose, when compared with the membrane-bound receptor.
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Affiliation(s)
- H Lee
- Biochemisches Institut der Universität zu Kiel
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33
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Baenziger JU, Green ED. Pituitary glycoprotein hormone oligosaccharides: structure, synthesis and function of the asparagine-linked oligosaccharides on lutropin, follitropin and thyrotropin. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 947:287-306. [PMID: 3130893 DOI: 10.1016/0304-4157(88)90012-3] [Citation(s) in RCA: 211] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Luteinizing hormone (LH), follicle-stimulating hormone (FSH) and thyroid-stimulating hormone (TSH) from pituitary and chorionic gonadotropin (CG) from placenta are a family of closely related glycoproteins. Each hormone is a heterodimer, consisting of an alpha- and a beta-subunit. Within an animal species, the alpha-subunits of all four glyco-protein hormones have an identical amino acid sequence, whereas each beta-subunit is distinct and confers hormone-specific features to the heterodimer. LH and FSH are synthesized within the same cell, the gonadotroph of the anterior pituitary, but are predominantly stored in separate secretory granules. We have characterized the asparagine-linked oligosaccharides on bovine, ovine and human LH, FSH and TSH. The various pituitary hormones were found to contain unique sulfated oligosaccharides with the terminal sequence SO4-4GalNAc beta 1----4GlcNAc beta 1----2Man alpha, sialylated oligosaccharides with the terminal sequence SA alpha Gal beta GlcNAc beta Man alpha, or both sulfated and sialylated structures. Despite synthesis of LH and FSH in the same pituitary cell, sulfated oligosaccharides predominate on LH while sialylated oligosaccharides predominate on FSH for all three animal species. We have examined the reactions leading to synthesis of the sulfated oligosaccharides to determine which steps are hormone specific. The sulfotransferase is oligosaccharide specific, requiring only the sequence GalNAc beta 1----4GlcNAc beta 1----2Man alpha. In contrast, the GalNAc-transferase appears to be protein specific, accounting for the preferential addition of GalNAc to LH, TSH, and free (uncombined) alpha-subunits compared with FSH and other pituitary glycoproteins. The predominance of sulfated oligosaccharide structures on LH may account for sorting of LH and FSH into separate secretory granules. Differences in sulfation and sialylation of LH, FSH and TSH may also play a role in the regulation of hormone bioactivity.
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Affiliation(s)
- J U Baenziger
- Department of Pathology, Washington University Medical School, St. Louis, MO 63110
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34
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Oka JA, Weigel PH. Effects of hyperosmolarity on ligand processing and receptor recycling in the hepatic galactosyl receptor system. J Cell Biochem 1988; 36:169-83. [PMID: 2833526 DOI: 10.1002/jcb.240360208] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Binding, endocytosis, and degradation of asialo-orosomucoid (ASOR) mediated by the galactosyl (Gal) receptor were examined in isolated rat hepatocytes in complete media supplemented with an osmolite. The specific binding of 125I-ASOR to cells at 4 degrees C was unaffected by up to 0.4 M sucrose or NaCl. Unlike sucrose or NaCl, mannitol stimulated 125I-ASOR binding at low concentrations but inhibited binding at higher concentrations. Continuous internalization at 37 degrees C, which requires receptor recycling, was completely blocked at 0.2 M sucrose or 0.15 M NaCl, corresponding in each case to a total osmolality of about 550 mmol/kg. This effect was reversed and endocytic function was restored by washing the cells, indicating that cell viability was unaffected. The rate of degradation of internalized 125I-ASOR was also inhibited by increasing sucrose concentrations. This inhibition is due to a block in the delivery of ligand to lysosomes and not an effect on degradation per se. In the presence of 0.2 M sucrose, the rate and extent of endocytosis of surface-bound 125I-ASOR were, respectively, 33.0 +/- 8.1% and 69.4 +/- 10.5% (n = 8) of the control without sucrose. Under these conditions, the dissociation of internalized receptor-ASOR complexes was completely inhibited. When sucrose was added, the effect on the endocytosis of surface-bound 125I-ASOR was virtually immediate. Previous studies showed that about 40% of the surface-bound 125I-ASOR which is internalized can return to the cell surface still bound to receptor (Weigel and Oka: J Biol Chem 259:1150, 1984). If 0.2 M sucrose was added after endocytosis occurred, 125I-ASOR still returned to the cell surface, although the rate and extent of return were inhibited by more than 50%. Interestingly, hyperosmolarity is the only treatment we have found which can reversibly inhibit, although only partially, the endocytosis of surface-bound 125I-ASOR.
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Affiliation(s)
- J A Oka
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77550
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Wong TC, Townsend RR, Lee YC. Synthesis of D-galactosamine derivatives and binding studies using isolated rat hepatocytes. Carbohydr Res 1987; 170:27-46. [PMID: 3435903 DOI: 10.1016/0008-6215(87)85003-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Derivatives of glycosides of D-galactosamine were prepared in order to study further the binding requirement of the Gal/GalNAc receptor in mammalian hepatocytes. These structures included N-propanoyl, N-benzoyl, and N,N-phthaloyl derivatives of 2-hydroxyethyl 2-amino-2-deoxy-beta-D-galactopyranoside, 6-amino-hex-1-yl 2-deoxy-2-(trifluoroacetamido)-beta-D-galactopyranoside, the mono- and di-O-methyl derivatives of allyl 2-acetamido-2-deoxy-beta-D-galactopyranoside, and allyl 2-acetamido-2,4-dideoxy-4-fluoro-alpha-D-galactopyranoside. The inhibition results confirmed some of our previous findings on the involvement of the hydroxyl groups, and provided new information on the involvement of the N-substituent, as well as on the requirement of hydrogen bonding of the 4-hydroxyl group in binding.
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Affiliation(s)
- T C Wong
- Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218
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Lee RT, Lee YC. Preparation of a high-affinity photolabeling reagent for the Gal/GalNAc lectin of mammalian liver: demonstration of galactose-combining sites on each subunit of rabbit hepatic lectin. Biochemistry 1986; 25:6835-41. [PMID: 2432926 DOI: 10.1021/bi00370a016] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
On the basis of the knowledge that the D-galactose/N-acetyl-D-galactosamine-specific lectin of rabbit liver can tolerate a large group on the C-6 hydroxyl group of a galactoside [Lee, R. T. (1982) Biochemistry 21, 1045-1050], we prepared a high-affinity photolabeling reagent for this lectin from a triantennary glycopeptide fraction of asialofetuin. The C-6 hydroxyl group of a D-galactopyranoside was converted, under mild conditions, into a primary amino group. The procedure involves conversion of the hydroxyl group to an oxo group with galactose oxidase, followed by reductive amination using benzylamine and sodium cyanoborohydride. Catalytic hydrogenolysis of the benzylamino derivative yielded the desired 6-amino-6-deoxy-D-galactoside. A 4-azidobenzoyl group was attached to the newly produced amino group to yield a photoactivatable affinity-labeling reagent. The reagent labeled the Triton-solubilized, purified hepatic lectins of rabbit and rat in a photo- and affinity-dependent manner. All the polypeptide subunits of the lectins were labeled, indicating that each subunit contains at least one D-galactose-combining site. In the case of the rabbit hepatic lectin, the minor subunit (46 kDa) was labeled more efficiently than the major one (40 kDa).
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Lee RT, Wong TC, Lee YC. Synthesis of 6′-Aminohexyl 2-Acetamido-2-deoxy-D-galactoside Isomers and a Unique Isomerization Catalyzed by Ion Exchange Resin. J Carbohydr Chem 1986. [DOI: 10.1080/07328308608058840] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Leffler H, Barondes SH. Specificity of binding of three soluble rat lung lectins to substituted and unsubstituted mammalian beta-galactosides. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(18)67499-x] [Citation(s) in RCA: 255] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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The binding of fucose-containing glycoproteins by hepatic lectins. The binding specificity of the rat liver fucose lectin. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(17)38409-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Heeb MJ, Marini AM, Gabriel O. Factors affecting binding of galacto ligands to Actinomyces viscosus lectin. Infect Immun 1985; 47:61-7. [PMID: 2578122 PMCID: PMC261466 DOI: 10.1128/iai.47.1.61-67.1985] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The specificity requirements for the binding of Actinomyces viscosus T14V were examined by testing simple sugars, oligopeptides, and glycoproteins as inhibitors of the aggregation of glycoprotein-coated latex beads and washed A. viscosus cells. Lactose was the most inhibitory simple sugar; D-fucose and D-galactose were equally inhibitory, methyl-alpha-D-fucoside was slightly less inhibitory, and L-fucose and raffinose were not inhibitory. The concentration of galactose residues required for 50% inhibition of aggregation was 15 times higher in the form of lactose than in the form of asialoglycoprotein, suggesting an enhancement of lectin binding when galactose residues are clustered. However, when the inhibitory power of bi-, tri-, and tetraantennary asialooligopeptides of alpha 1-acid glycoprotein was compared with that of equivalent concentrations of galactose in the form of lactose, the biantennary form was slightly less effective than lactose, the triantennary form was approximately as effective as lactose, and the tetraantennary form was slightly more effective than lactose. Steric interference may prevent this type of clustering from enhancing lectin binding. The O-linked asialooligopeptides of asialofetuin were 10 times more inhibitory than an equivalent concentration of galactose in the form of N-linked asialooligopeptides. Thus, galactose beta-1----3 linked to N-acetylgalactosamine exhibits greater specificity for the A. viscosus lectin than does galactose beta-1----4 linked to N-acetylglucosamine. These results, taken together with previously reported data, are consistent with a lectin of low affinity, binding enhanced by multivalency, and specificity for beta-linked galactose.
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Recycling of the hepatic asialoglycoprotein receptor in isolated rat hepatocytes. Receptor-ligand complexes in an intracellular slowly dissociating pool return to the cell surface prior to dissociation. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)43580-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Abstract
Asialo- (i.e., galactose-terminal) glycoproteins are specifically and avidly recognized by a mammalian hepatic parenchymal cell receptor. This receptor, itself a glycoprotein, binds ligand molecules and directs their delivery to lysosomes for catabolism. The receptor is reutilized during this process of receptor-mediated endocytosis. Ligand specificity is conferred by galactose or N-acetyl-galactosamine at the nonreducing termini of the oligosaccharide chains. The receptor appears to be a transmembrane protein and is localized both to the cell surface as well as to several membranous intracellular compartments.
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Recycling of the asialoglycoprotein receptor in isolated rat hepatocytes. Dissociation of internalized ligand from receptor occurs in two kinetically and thermally distinguishable compartments. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(17)44450-4] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Springer GF, Cheingsong-Popov R, Schirrmacher V, Desai PR, Tegtmeyer H. Proposed molecular basis of murine tumor cell-hepatocyte interaction. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(20)81949-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Zehavi U, El-On J, Pearlman E, Abrahams JC, Greenblatt CL. Binding of Leishmania promastigotes to macrophages. ZEITSCHRIFT FUR PARASITENKUNDE (BERLIN, GERMANY) 1983; 69:405-14. [PMID: 6624192 DOI: 10.1007/bf00927696] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Leishmania tropica promastigotes are easily attached to and engulfed by C3H peritoneal macrophages in vitro at 37 degrees C. Different sugars at 0.3-0.5 M inhibited in vitro the attachment of L. tropica promastigotes to C3H peritoneal macrophages with lactose (Gal-beta [1 leads to 4]Glc) being the most efficient. Inhibition of attachment is also affected by pre-treatment of promastigotes with galactose oxidase. Oligosaccharides extending from promastigote and amastigote cell surfaces contain an important proportion of non-reducing galactose as does the carbohydrate-rich factor (EF) excreted by promastigotes of L. tropica and L. donovani. This study suggests that Leishmania, an obligatory intracellular parasite, uses as a means of entering the host cell a cellular mechanism similar to that used in the removal of damaged cells from blood circulation. This mechanism is assumed to take advantage of the exposed sugars, particularly the exposed non-reducing galactose, on the parasite surface during the stage of attachment. Once the parasite is inside the cell, the EF it produces might have a protective function, being inhibitory to some of the host cell lysosomal enzymes.
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