Chemistry-Driven Molecular Tools to Study Airway Mucin O-Glycosylation
Final Report Abstract
The mucin O-glycoproteins are major players in inflammatory-infective airway diseases like COPD, cystic fibrosis and asthma. Colonization of the respiratory tracts by opportunistic bacteria results in inflammatory insults of the tissues. Specific carbohydrate structures on the mucin glycoproteins may serve as ligands during airway infections. Better understanding of host-pathogen interactions are desired for fine-tuning of new diagnostic applications, as well as to develop anti-adhesive drugs. In this work we aimed to synthesize mucin peptide tandem repeats modified with different elongated core glycan structures and apply the obtained glycopeptide library in microarray binding studies. We thereby aimed to identify new glycan or glycopeptide ligands to different microbes and viruses that are responsible for triggering of acute exacerbations in airway disease patients. Mucin glycoproteins further play critical roles in tumor progression, the obtained mucin glycopeptide library were therefore also of interest to study binding specificity of cancer lectins (glycan binding proteins) and antibodies induced from synthetic anti-tumor vaccines. In order to study binding events of microbe and virus lectins involved in chronic insults of the airways in patients suffering from COPD and cystic fibrosis, the synthesis focused around the secreted mucin MUC5B tandem repeat glycopeptide, and the membrane bound MUC1 and MUC4 tandem repeats, that are highly expressed in the airways. Efficient convergent synthetic routes were developed to prepare elongated mucin core glycosylated amino acids and library of about 200 mucin glycopeptides were constructed consisting of tumor associated carbohydrate antigens and elongated core structures. The synthetic glycopeptides were enzymatically modified and a library of sialylated glycopeptides were generated. Fucosylated and sulphated structures remains to be prepared. Microarray studies of adenovirus lectins were initiated, but the microarray detection strategy needs to be optimized. Glycopeptide microarray binding studies of P. aeuroginosa, S. aureus, und H. influenzae will start when the library has been further diversified with fucosylated glycopeptides, the terminal fucosylated and sialylated structures are considered to be very important in many bacterial binding recognition events. Glycopeptide microarray studies were performed for analysis of antibodies induced with synthetic vaccines. New knowledge about the nature of antibody immune response to glycopeptide antigens was generated. Glycopeptide microarray studies were performed for analysis of Galectin-3. Important new knowledge was obtained to understand glycan binding events in tumor-cell migration. The synthetic mucin glycopeptides were further used in MS-fragmentation studies. Characteristic oxonium ions were identified that discriminate between specific glycan structural isomers.
Publications
- A Unified Strategy for the Synthesis of Mucin Cores 1-4 Saccharides and the Assembled Multivalent Glycopeptides, Chem Eur. J. 2013 19, 17001-17010
Pett, C., Schorlemer, M., Westerlind, U.
(See online at https://doi.org/10.1002/chem.201302921) - A Convergent Strategy for the Synthesis of Type-1 Elongated Mucin Cores 1-3 and the Corresponding Glycopeptides, Chem. Eur. J., 2014, 20, 7287-7299
Pett, C., Westerlind, U.
(See online at https://doi.org/10.1002/chem.201400162) - Arraying the post-translational glycoproteome (PTG), Curr. Opin. Chem. Biol. 2014 18, 62-69
Blixt, O., Westerlind, U.
(See online at https://doi.org/10.1016/j.cbpa.2014.01.002) - Assignment of Saccharide Identities through Analysis of Oxonium Ion Fragmentation Pathways in LC-MS/MS of Glycopeptides, J. Proteom. Res. 2014, 13, 6024-6032
Halim, A.; Westerlind, U.; Pett, C.; Schorlemer, M.; Rüetschi, U.; Brinkmalm, G.; Sihlbom, C.; Lengqvist, J.; Larson, G.; Nilsson, J.
(See online at https://doi.org/10.1021/pr500898r) - Antibody Induction Directed Against the Tumor-Associated MUC4 Glycoprotein. ChemBioChem 2015, 16, 959-967
Cai, H.; Palitzsch, B.; Hartmann, S.; Stergiou, N.; Kunz, H.; Schmitt, E.; Westerlind, U.
(See online at https://doi.org/10.1002/cbic.201402689) - Distinctive MS/MS fragmentation pathways of glycopeptide-generated oxonium ions provide evidence of the glycan structure, Chem Eur. J. 2016, 22, 1114-1124
Yu, J.; Schorlemer, M.; Gomez Toledo, A.; Pett, C.; Sihlbom, C.; Larson, G.; Westerlind, U., Nilsson, J.
(See online at https://doi.org/10.1002/chem.201503659) - Microarray Analysis of Antibodies Induced with Synthetic Antitumor Vaccines: Specificity against Diverse Mucin Core Structures. Chemistry Vol 23 Issue 16, March 17, 2017, Pages 3875-3884
Pett, C.; Cai, H.; Liu, J.; Palitzsch, B.; Schorlemer, M.; Hartmann, S.; Stergiou, N.; Lu, M.; Kunz, H.; Schmitt, E.; Westerlind, U.
(See online at https://doi.org/10.1002/chem.201603921)
