Pub Date : 2023-07-01Epub Date: 2023-07-09DOI: 10.1002/pgr2.6
Israel Vlodavsky, Yasmin Kayal, Maram Hilwi, Soaad Soboh, Ralph D Sanderson, Neta Ilan
Heparanase (Hpa1) is expressed by tumor cells and cells of the tumor microenvironment and functions extracellularly to remodel the extracellular matrix (ECM) and regulate the bioavailability of ECM-bound factors, augmenting, among other effects, gene transcription, autophagy, exosome formation, and heparan sulfate (HS) turnover. Much of the impact of heparanase on tumor progression is related to its function in mediating tumor-host crosstalk, priming the tumor microenvironment to better support tumor growth, metastasis, and chemoresistance. The enzyme appears to fulfill some normal functions associated, for example, with vesicular traffic, lysosomal-based secretion, autophagy, HS turnover, and gene transcription. It activates cells of the innate immune system, promotes the formation of exosomes and autophagosomes, and stimulates signal transduction pathways via enzymatic and nonenzymatic activities. These effects dynamically impact multiple regulatory pathways that together drive tumor growth, dissemination, and drug resistance as well as inflammatory responses. The emerging premise is that heparanase expressed by tumor cells, immune cells, endothelial cells, and other cells of the tumor microenvironment is a key regulator of the aggressive phenotype of cancer, an important contributor to the poor outcome of cancer patients and a valid target for therapy. So far, however, antiheparanase-based therapy has not been implemented in the clinic. Unlike heparanase, heparanase-2 (Hpa2), a close homolog of heparanase (Hpa1), does not undergo proteolytic processing and hence lacks intrinsic HS-degrading activity, the hallmark of heparanase. Hpa2 retains the capacity to bind heparin/HS and exhibits an even higher affinity towards HS than heparanase, thus competing for HS binding and inhibiting heparanase enzymatic activity. It appears that Hpa2 functions as a natural inhibitor of Hpa1 regulates the expression of selected genes that maintain tissue hemostasis and normal function, and plays a protective role against cancer and inflammation, together emphasizing the significance of maintaining a proper balance between Hpa1 and Hpa2.
{"title":"Heparanase-A single protein with multiple enzymatic and nonenzymatic functions.","authors":"Israel Vlodavsky, Yasmin Kayal, Maram Hilwi, Soaad Soboh, Ralph D Sanderson, Neta Ilan","doi":"10.1002/pgr2.6","DOIUrl":"10.1002/pgr2.6","url":null,"abstract":"<p><p>Heparanase (Hpa1) is expressed by tumor cells and cells of the tumor microenvironment and functions extracellularly to remodel the extracellular matrix (ECM) and regulate the bioavailability of ECM-bound factors, augmenting, among other effects, gene transcription, autophagy, exosome formation, and heparan sulfate (HS) turnover. Much of the impact of heparanase on tumor progression is related to its function in mediating tumor-host crosstalk, priming the tumor microenvironment to better support tumor growth, metastasis, and chemoresistance. The enzyme appears to fulfill some normal functions associated, for example, with vesicular traffic, lysosomal-based secretion, autophagy, HS turnover, and gene transcription. It activates cells of the innate immune system, promotes the formation of exosomes and autophagosomes, and stimulates signal transduction pathways via enzymatic and nonenzymatic activities. These effects dynamically impact multiple regulatory pathways that together drive tumor growth, dissemination, and drug resistance as well as inflammatory responses. The emerging premise is that heparanase expressed by tumor cells, immune cells, endothelial cells, and other cells of the tumor microenvironment is a key regulator of the aggressive phenotype of cancer, an important contributor to the poor outcome of cancer patients and a valid target for therapy. So far, however, antiheparanase-based therapy has not been implemented in the clinic. Unlike heparanase, heparanase-2 (Hpa2), a close homolog of heparanase (Hpa1), does not undergo proteolytic processing and hence lacks intrinsic HS-degrading activity, the hallmark of heparanase. Hpa2 retains the capacity to bind heparin/HS and exhibits an even higher affinity towards HS than heparanase, thus competing for HS binding and inhibiting heparanase enzymatic activity. It appears that Hpa2 functions as a natural inhibitor of Hpa1 regulates the expression of selected genes that maintain tissue hemostasis and normal function, and plays a protective role against cancer and inflammation, together emphasizing the significance of maintaining a proper balance between Hpa1 and Hpa2.</p>","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10398610/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10325441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to “Functional and structural insights into human <i>N</i>‐deacetylase/<i>N</i>‐sulfotransferase activities”","authors":"","doi":"10.1002/pgr2.12","DOIUrl":"https://doi.org/10.1002/pgr2.12","url":null,"abstract":"","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135857748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martyna Maszota‐Zieleniak, Adam Liwo, Sylvie Ricard‐Blum, Sergey A. Samsonov
Abstract We have previously shown that the extracellular domains of the four syndecans are intrinsically disordered, and adopt a wide range of conformations. We report here the building of coarse‐grained models of the extracellular domains of human syndecans 2 and 4 using small‐angle X‐ray scattering restraints. One, two or three heparan sulfate (HS) hexadecasaccharides, (IdoA[2S]GlcNS[6S]) 8 , were attached to three serine residues of the core proteins, resulting in eight variants for each syndecan that were used for all‐atom molecular dynamics (MD) simulations (0.5–1 µs). Syndecan‐4 had a larger conformational diversity than syndecan‐2, and remained extended during MD simulations in absence of HS whereas syndecan‐2 adopted more compact conformations. Their core proteins thus appeared to be structurally distinct. The HS chains also behave differently, the middle chain being more flexible in syndecan‐4, and the third chain being able to interact with the core protein regions mediating cell adhesion. The cell adhesion sites on both core proteins were flexible, with or without HS chains, the NXIP motif of syndecan‐2 being located in a particularly flexible region. In conclusion, the HS chains induce moderate changes in the conformational dynamics of both syndecans, depending on the number of HS chains and their location on the core protein, and on the core protein itself.
{"title":"Interplay of heparan sulfate chains with the core proteins of syndecans 2 and 4","authors":"Martyna Maszota‐Zieleniak, Adam Liwo, Sylvie Ricard‐Blum, Sergey A. Samsonov","doi":"10.1002/pgr2.10","DOIUrl":"https://doi.org/10.1002/pgr2.10","url":null,"abstract":"Abstract We have previously shown that the extracellular domains of the four syndecans are intrinsically disordered, and adopt a wide range of conformations. We report here the building of coarse‐grained models of the extracellular domains of human syndecans 2 and 4 using small‐angle X‐ray scattering restraints. One, two or three heparan sulfate (HS) hexadecasaccharides, (IdoA[2S]GlcNS[6S]) 8 , were attached to three serine residues of the core proteins, resulting in eight variants for each syndecan that were used for all‐atom molecular dynamics (MD) simulations (0.5–1 µs). Syndecan‐4 had a larger conformational diversity than syndecan‐2, and remained extended during MD simulations in absence of HS whereas syndecan‐2 adopted more compact conformations. Their core proteins thus appeared to be structurally distinct. The HS chains also behave differently, the middle chain being more flexible in syndecan‐4, and the third chain being able to interact with the core protein regions mediating cell adhesion. The cell adhesion sites on both core proteins were flexible, with or without HS chains, the NXIP motif of syndecan‐2 being located in a particularly flexible region. In conclusion, the HS chains induce moderate changes in the conformational dynamics of both syndecans, depending on the number of HS chains and their location on the core protein, and on the core protein itself.","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136260478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01Epub Date: 2023-08-09DOI: 10.1002/pgr2.9
Atsuko Hayashida, Hajirah N Saeed, Fuming Zhang, Yuefan Song, Jian Liu, William C Parks, Paulo J M Bispo, Pyong Woo Park
A large number of bacterial pathogens bind to host extracellular matrix (ECM) components. For example, many Gram-negative and Gram-positive pathogens express binding proteins for fibronectin (FN) on their cell surface. Mutagenesis studies of bacterial FN-binding proteins have demonstrated their importance in pathogenesis in preclinical animal models. However, means to draw on these findings to design therapeutic approaches that specifically target FN-bacteria interactions have not been successful because bacterial pathogens can elaborate several FN-binding proteins and also because FN is an essential protein and likely a nondruggable target. Here we report that select heparan compounds potently inhibit Streptococcus pneumoniae infection of injured corneas in mice. Using intact heparan sulfate (HS) and heparin (HP), heparinase-digested fragments of HS, HP oligosaccharides, and chemically or chemoenzymatically modified heparan compounds, we found that inhibition of S. pneumoniae corneal infection by heparan compounds is not mediated by simple charge effects but by a selective sulfate group. Removal of 2-O-sulfates significantly inhibited the ability of HP to inhibit S. pneumoniae corneal infection, whereas the addition of 2-O-sulfates to heparosan (H) significantly increased H's ability to inhibit bacterial corneal infection. Proximity ligation assays indicated that S. pneumoniae attaches directly to FN fibrils in the corneal epithelial ECM and that HS and HP specifically inhibit this binding interaction in a 2-O-sulfate-dependent manner. These data suggest that heparan compounds containing 2-O-sulfate groups protect against S. pneumoniae corneal infection by inhibiting bacterial attachment to FN fibrils in the subepithelial ECM of injured corneas. Moreover, 2-O-sulfated heparan compounds significantly inhibited corneal infection in immunocompromised hosts, by a clinical keratitis isolate of S. pneumoniae, and also when topically administered in a therapeutic manner. These findings suggest that the administration of nonanticoagulant 2-O-sulfated heparan compounds may represent a plausible approach to the treatment of S. pneumoniae keratitis.
{"title":"Sulfated motifs in heparan sulfate inhibit <i>Streptococcus pneumoniae</i> adhesion onto fibronectin and attenuate corneal infection.","authors":"Atsuko Hayashida, Hajirah N Saeed, Fuming Zhang, Yuefan Song, Jian Liu, William C Parks, Paulo J M Bispo, Pyong Woo Park","doi":"10.1002/pgr2.9","DOIUrl":"10.1002/pgr2.9","url":null,"abstract":"<p><p>A large number of bacterial pathogens bind to host extracellular matrix (ECM) components. For example, many Gram-negative and Gram-positive pathogens express binding proteins for fibronectin (FN) on their cell surface. Mutagenesis studies of bacterial FN-binding proteins have demonstrated their importance in pathogenesis in preclinical animal models. However, means to draw on these findings to design therapeutic approaches that specifically target FN-bacteria interactions have not been successful because bacterial pathogens can elaborate several FN-binding proteins and also because FN is an essential protein and likely a nondruggable target. Here we report that select heparan compounds potently inhibit <i>Streptococcus pneumoniae</i> infection of injured corneas in mice. Using intact heparan sulfate (HS) and heparin (HP), heparinase-digested fragments of HS, HP oligosaccharides, and chemically or chemoenzymatically modified heparan compounds, we found that inhibition of <i>S. pneumoniae</i> corneal infection by heparan compounds is not mediated by simple charge effects but by a selective sulfate group. Removal of 2-<i>O</i>-sulfates significantly inhibited the ability of HP to inhibit <i>S. pneumoniae</i> corneal infection, whereas the addition of 2-<i>O</i>-sulfates to heparosan (H) significantly increased H's ability to inhibit bacterial corneal infection. Proximity ligation assays indicated that <i>S. pneumoniae</i> attaches directly to FN fibrils in the corneal epithelial ECM and that HS and HP specifically inhibit this binding interaction in a 2-<i>O</i>-sulfate-dependent manner. These data suggest that heparan compounds containing 2-<i>O</i>-sulfate groups protect against <i>S. pneumoniae</i> corneal infection by inhibiting bacterial attachment to FN fibrils in the subepithelial ECM of injured corneas. Moreover, 2-<i>O</i>-sulfated heparan compounds significantly inhibited corneal infection in immunocompromised hosts, by a clinical keratitis isolate of <i>S. pneumoniae</i>, and also when topically administered in a therapeutic manner. These findings suggest that the administration of nonanticoagulant 2-<i>O</i>-sulfated heparan compounds may represent a plausible approach to the treatment of <i>S. pneumoniae</i> keratitis.</p>","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11218895/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84998073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The role of hyperglycemia‐evoked intracellular hyaluronan accumulation and its activity on the autophagic and endoplasmic reticulum stress pathways","authors":"A. Wang, Aimin Wang, V. Hascall","doi":"10.1002/pgr2.7","DOIUrl":"https://doi.org/10.1002/pgr2.7","url":null,"abstract":"","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84421742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sylvain D. Vallet, T. Annaval, R. Vivès, Emeline Richard, Jérôme Hénault, C. Le Narvor, D. Bonnaffé, B. Priem, R. Wild, H. Lortat‐Jacob
Heparan sulfate (HS) is a linear polysaccharide composed of a glucuronic acid (GlcA)‐N‐acetyl‐glucosamine (GlcNAc) disaccharide repeat motif, polymerized by the EXT1–EXT2 complex. It is extensively modified by a series of Golgi localized enzymes, that generate distinct saccharide sequences involved in the binding and the regulation of numerous protein partners. N‐deacetylase/N‐sulfotransferase (NDST), of which four isoforms have been identified in mammals, are involved in the first step of this process and catalyze both the N‐deacetylation of the GlcNAc residues into GlcNH2 and its re‐N‐sulfation into GlcNS residues. Further modifications of the HS chain depend on this first maturation event, NDST action is, therefore, key to HS biosynthesis. However, although the sulfotransferase domain of NDST1 has been characterized at the structural level some 20 years ago, information on the overall structure and activity of the enzyme are still lacking. Here, we report the characterization of the two most expressed NDSTs in humans, NDST1 and NDST2, and a model structure of NDST1 homodimer using cryoelectron microscopy combined with AlphaFold2 modeling. Structure‐driven mutagenesis along with two bioassays to follow the protein activities allowed us to characterize the kinetics of the deacetylation and sulfoaddition and to identify the residue H529 as necessary for N‐deacetylation. These results shed light on a poorly understood family of enzymes and will help deciphering the molecular basis for HS and heparin maturation.
硫酸肝素(HS)是由葡萄糖醛酸(GlcA) - N -乙酰-氨基葡萄糖(GlcNAc)双糖重复基序组成的线性多糖,由EXT1-EXT2络合物聚合而成。它被一系列高尔基定位酶广泛修饰,这些酶产生不同的糖序列,参与许多蛋白质伴侣的结合和调节。N -去乙酰化酶/N -磺基转移酶(NDST)参与了这一过程的第一步,并催化GlcNAc残基的N -去乙酰化转化为GlcNH2和其再- N -磺化转化为GlcNS残基。NDST在哺乳动物中已鉴定出四种亚型。HS链的进一步修饰依赖于这第一个成熟事件,因此NDST作用是HS生物合成的关键。然而,尽管NDST1的硫转移酶结构域在20多年前就已经在结构水平上得到了表征,但关于该酶的整体结构和活性的信息仍然缺乏。在这里,我们报道了两种在人类中表达最多的NDST1和NDST2的特征,以及NDST1同型二聚体的模型结构,使用冷冻电镜结合AlphaFold2模型。结构驱动诱变以及跟踪蛋白质活性的两次生物测定使我们能够表征脱乙酰化和磺化的动力学,并确定残留物H529是N -去乙酰化所必需的。这些结果揭示了一个鲜为人知的酶家族,并将有助于破译HS和肝素成熟的分子基础。
{"title":"Functional and structural insights into human N‐deacetylase/N‐sulfotransferase activities","authors":"Sylvain D. Vallet, T. Annaval, R. Vivès, Emeline Richard, Jérôme Hénault, C. Le Narvor, D. Bonnaffé, B. Priem, R. Wild, H. Lortat‐Jacob","doi":"10.1002/pgr2.8","DOIUrl":"https://doi.org/10.1002/pgr2.8","url":null,"abstract":"Heparan sulfate (HS) is a linear polysaccharide composed of a glucuronic acid (GlcA)‐N‐acetyl‐glucosamine (GlcNAc) disaccharide repeat motif, polymerized by the EXT1–EXT2 complex. It is extensively modified by a series of Golgi localized enzymes, that generate distinct saccharide sequences involved in the binding and the regulation of numerous protein partners. N‐deacetylase/N‐sulfotransferase (NDST), of which four isoforms have been identified in mammals, are involved in the first step of this process and catalyze both the N‐deacetylation of the GlcNAc residues into GlcNH2 and its re‐N‐sulfation into GlcNS residues. Further modifications of the HS chain depend on this first maturation event, NDST action is, therefore, key to HS biosynthesis. However, although the sulfotransferase domain of NDST1 has been characterized at the structural level some 20 years ago, information on the overall structure and activity of the enzyme are still lacking. Here, we report the characterization of the two most expressed NDSTs in humans, NDST1 and NDST2, and a model structure of NDST1 homodimer using cryoelectron microscopy combined with AlphaFold2 modeling. Structure‐driven mutagenesis along with two bioassays to follow the protein activities allowed us to characterize the kinetics of the deacetylation and sulfoaddition and to identify the residue H529 as necessary for N‐deacetylation. These results shed light on a poorly understood family of enzymes and will help deciphering the molecular basis for HS and heparin maturation.","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87913298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Functional organization of extracellular hyaluronan, CD44, and RHAMM","authors":"M. Cowman, E. Turley","doi":"10.1002/pgr2.4","DOIUrl":"https://doi.org/10.1002/pgr2.4","url":null,"abstract":"","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76612066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-01Epub Date: 2023-06-01DOI: 10.1002/pgr2.3
Michael Nguyen, Tanaya Walimbe, Andrew Woolley, John Paderi, Alyssa Panitch
Many endothelial complications, whether from surgical or pathological origins, can result in the denudation of the endothelial layer and the exposure of collagen. Exposure of collagen results in the activation of platelets, leading to thrombotic and inflammatory cascades that ultimately result in vessel stenosis. We have previously reported the use of peptide-GAG compounds to target exposed collagen following endothelial injury. In this paper we optimize the spacer sequence of our collagen binding peptide to increase its conjugation to GAG backbones and increase the peptide-GAG collagen binding affinity by increasing peptide C-terminal cationic charge. Furthermore, we demonstrate the use of these molecules to inhibit platelet activation through collagen blocking, as well as their localization to exposed vascular collagen following systemic delivery. Altogether, optimization of peptide sequence and linkage chemistry can allow for increased conjugation and function, having implications for glycoconjugate use in other clinical applications.
许多内皮并发症,无论是手术还是病理引起的,都会导致内皮层剥脱和胶原蛋白暴露。胶原蛋白的暴露会导致血小板活化,引发血栓和炎症级联反应,最终导致血管狭窄。我们以前曾报道过使用肽-GAG 化合物来靶向内皮损伤后暴露的胶原蛋白。在本文中,我们优化了胶原蛋白结合肽的间隔序列,以增加其与 GAG 骨架的连接,并通过增加肽 C 端阳离子电荷来提高肽-GAG 胶原蛋白结合亲和力。此外,我们还证明了这些分子可通过阻断胶原蛋白来抑制血小板活化,并可在全身给药后定位到暴露的血管胶原蛋白上。总之,肽序列和连接化学的优化可以提高共轭能力和功能,并对糖共轭物在其他临床应用中的使用产生影响。
{"title":"Synthesis and Optimization of Collagen-targeting Peptide-Glycosaminoglycans for Inhibition of Platelets Following Endothelial Injury.","authors":"Michael Nguyen, Tanaya Walimbe, Andrew Woolley, John Paderi, Alyssa Panitch","doi":"10.1002/pgr2.3","DOIUrl":"10.1002/pgr2.3","url":null,"abstract":"<p><p>Many endothelial complications, whether from surgical or pathological origins, can result in the denudation of the endothelial layer and the exposure of collagen. Exposure of collagen results in the activation of platelets, leading to thrombotic and inflammatory cascades that ultimately result in vessel stenosis. We have previously reported the use of peptide-GAG compounds to target exposed collagen following endothelial injury. In this paper we optimize the spacer sequence of our collagen binding peptide to increase its conjugation to GAG backbones and increase the peptide-GAG collagen binding affinity by increasing peptide C-terminal cationic charge. Furthermore, we demonstrate the use of these molecules to inhibit platelet activation through collagen blocking, as well as their localization to exposed vascular collagen following systemic delivery. Altogether, optimization of peptide sequence and linkage chemistry can allow for increased conjugation and function, having implications for glycoconjugate use in other clinical applications.</p>","PeriodicalId":74585,"journal":{"name":"Proteoglycan research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11178347/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75867783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}