This project is directed to the characterization of the recently described siglec family of cell adhesion receptors, a subfamily of the immunoglobulin superfamily. The extracellular domains of the siglecs have a homologous N-terminal Ig domain which confers the ability to bind to sialic acid containing carbohydrate groups of glycoproteins and glycolipids. To date there are ten known members of the family, nine of which are expressed in cells of the immune system. Most is known about CD22 (siglec 2), which has been demonstrated to be an important regulatory molecule in the B cell antigen receptor complex, and has been implicated in dampening the immune response against autoantigens and autoimmune disease. In contrast to CD22, the detailed biology and functions of the other siglecs are poorly understood. The primary goal of the project will be to characterize the detailed specificities of murine and human siglecs towards sialyloligosaccharides of glycoproteins and glycolipids, and to develop multivalent sialyloligosaccharide probes unique to each siglec that will aid in their identification and characterization in complex biological systems. The initial objective will be to establish the affinity and specificity of each of the 11 known siglecs for >20 common sialyloligosaccharides found on carbohydrate groups of glycoproteins and glycolipids. The strategy will be to synthesize monovalent sialyloligosaccharides using a chemo-enzymatic approach, and establish the relative binding affinities using ELISA based and BiaCore based binding assays. This information will be used to design synthetic multivalent sialyloligosaccharide probes that distinguish each selectin in complex biological systems that will allow them to be used as tools in exploring their biological functions. A key biological resource to this project will be the availability of 'knockout mice' deficient in sialyltransferase genes involved in the synthesis of the sialoside ligands of siglecs. These mice will aid in the evaluation of the functional status of siglecs and provide insights into the role of these enzymes in the regulation of siglec function.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM060938-04
Application #
6621921
Study Section
Pathobiochemistry Study Section (PBC)
Program Officer
Marino, Pamela
Project Start
2000-04-01
Project End
2005-12-31
Budget Start
2003-01-01
Budget End
2003-12-31
Support Year
4
Fiscal Year
2003
Total Cost
$511,419
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Chen, Weihsu C; Sigal, Darren S; Saven, Alan et al. (2012) Targeting B lymphoma with nanoparticles bearing glycan ligands of CD22. Leuk Lymphoma 53:208-10
Rhee, Jin-Kyu; Baksh, Michael; Nycholat, Corwin et al. (2012) Glycan-targeted virus-like nanoparticles for photodynamic therapy. Biomacromolecules 13:2333-8
Zeng, Ying; Rademacher, Christoph; Nycholat, Corwin M et al. (2011) High affinity sialoside ligands of myelin associated glycoprotein. Bioorg Med Chem Lett 21:5045-9
Rhee, Jin-Kyu; Hovlid, Marisa; Fiedler, Jason D et al. (2011) Colorful virus-like particles: fluorescent protein packaging by the Q? capsid. Biomacromolecules 12:3977-81
Cui, Lina; Kitov, Pavel I; Completo, Gladys C et al. (2011) Supramolecular complexing of membane Siglec CD22 mediated by a polyvalent heterobifunctional ligand that templates on IgM. Bioconjug Chem 22:546-50
Rillahan, Cory D; Paulson, James C (2011) Glycan microarrays for decoding the glycome. Annu Rev Biochem 80:797-823
Abdu-Allah, Hajjaj H M; Watanabe, Kozo; Completo, Gladys C et al. (2011) CD22-antagonists with nanomolar potency: the synergistic effect of hydrophobic groups at C-2 and C-9 of sialic acid scaffold. Bioorg Med Chem 19:1966-71
Rillahan, Cory D; Brown, Steven J; Register, Amy C et al. (2011) High-throughput screening for inhibitors of sialyl- and fucosyltransferases. Angew Chem Int Ed Engl 50:12534-7
Belisle, Jennifer A; Horibata, Sachi; Jennifer, Gubbels A A et al. (2010) Identification of Siglec-9 as the receptor for MUC16 on human NK cells, B cells, and monocytes. Mol Cancer 9:118
Ramya, T N C; Weerapana, Eranthie; Liao, Lujian et al. (2010) In situ trans ligands of CD22 identified by glycan-protein photocross-linking-enabled proteomics. Mol Cell Proteomics 9:1339-51

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