The objective is to study the function of sulfated glycosaminoglycans (GAGs) in inflammation, with particular emphasis on the sulfation pattern ofthe heparan, chondroitin and dermatan sulfate. We have successfully created conditional mouse mutants altered in heparan sulfate biosynthesis and showed that altering overall sulfation diminishes inflammatory responses in the context of neutrophil rolling and infiltration. In contrast, altering heparan sulfate in leukocytes does not affect these processes and has only mild effects on adaptive immune responses. In this proposal, we plan to complete our studies of endothelial heparan sulfate by examining the impact of altered uronic acid 2-0-sulfafion and glucosamine 6-O-sulfation using mice with conditional alleles in these enzymes, and then extend this analysis to chondroitin-4-sulfate and dermatan sulfate. Because we anticipate that systemic mutations in chondroitin/dermatan sulfate biosynthesis will result in embryonic or perinatal lethality, we are preparing conditional alleles ofthe target genes and will alter their expression selectively in endothelial cells and myeloid cells. Specifically, we propose to: (1) Create mouse lines with conditional alleles of chondroitin polymerase-1, chondroitin 4-0-sulfotransferase-1, chondroitin 4-0-sulfotransferase-2 , and dermatan 4-0-sulfotransferase and in collaboration with Project 1 a conditional targeting construct to express Hyal4, an endo-N-acetylgalactosaminidase that can degrade chondroitin;(2) Examine the role of GAGs in leukocyte rolling, firm adhesion, and diapedesis in vitro using isolated endothelial cells derived from the mutants;(3) In collaboration with Projects 2 and 4, examine the in vivo consequences of altering endothelial GAGs on inflammation induced chemically, sterilely and by bacterial infection;and (4) Examine the consequences of altering endothelial glycosaminoglycans on vascular permeability. By focusing on inflammatory reactions that take place in the vasculature, the proposed studies build on a strong base of preliminary data, which together validate GAGs as potential targets for treating chronic inflammation and ischemic disease. Additionally, the project will provide model organisms for other investigators interested in the physiological function of glycosaminoglycans in other organ systems.
. Inflammation is the body's response to injury and infection. The central hypothesis of Project 3 is that glycosaminoglycans affects one or more steps in the inflammatory response and that their function can be ascertained by genetically manipulating their biosynthesis in endothelial cells, neutrophils, and macrophages.
|Schommer, Nina N; Muto, Jun; Nizet, Victor et al. (2014) Hyaluronan breakdown contributes to immune defense against group A Streptococcus. J Biol Chem 289:26914-21|
|Lin, Ann E; Autran, Chloe A; Espanola, Sophia D et al. (2014) Human milk oligosaccharides protect bladder epithelial cells against uropathogenic Escherichia coli invasion and cytotoxicity. J Infect Dis 209:389-98|
|Mooij, H L; Cabrales, P; Bernelot Moens, S J et al. (2014) Loss of function in heparan sulfate elongation genes EXT1 and EXT 2 results in improved nitric oxide bioavailability and endothelial function. J Am Heart Assoc 3:e001274|
|Padler-Karavani, Vered; Hurtado-Ziola, Nancy; Chang, Yung-Chi et al. (2014) Rapid evolution of binding specificities and expression patterns of inhibitory CD33-related Siglecs in primates. FASEB J 28:1280-93|
|Muto, Jun; Morioka, Yasuhide; Yamasaki, Kenshi et al. (2014) Hyaluronan digestion controls DC migration from the skin. J Clin Invest 124:1309-19|
|Xu, Ding; Esko, Jeffrey D (2014) Demystifying heparan sulfate-protein interactions. Annu Rev Biochem 83:129-57|
|Thacker, Bryan E; Xu, Ding; Lawrence, Roger et al. (2014) Heparan sulfate 3-O-sulfation: a rare modification in search of a function. Matrix Biol 35:60-72|
|Chang, Yung-Chi; Olson, Joshua; Beasley, Federico C et al. (2014) Group B Streptococcus engages an inhibitory Siglec through sialic acid mimicry to blunt innate immune and inflammatory responses in vivo. PLoS Pathog 10:e1003846|
|van Sorge, Nina M; Cole, Jason N; Kuipers, Kirsten et al. (2014) The classical lancefield antigen of group a Streptococcus is a virulence determinant with implications for vaccine design. Cell Host Microbe 15:729-40|
|Zhang, Bing; Xiao, Wenyuan; Qiu, Hong et al. (2014) Heparan sulfate deficiency disrupts developmental angiogenesis and causes congenital diaphragmatic hernia. J Clin Invest 124:209-21|
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