AIM To identify glycosylation-related genes in the HT29 derivative cell line, HT29-MTX-E12, showing differential expression on infection with Helicobacter pylori(H. pylori).METHODS Polarised HT29-MTX-E12 cells were in...AIM To identify glycosylation-related genes in the HT29 derivative cell line, HT29-MTX-E12, showing differential expression on infection with Helicobacter pylori(H. pylori).METHODS Polarised HT29-MTX-E12 cells were infected for 24 h with H. pylori strain 26695. After infection RNA was isolated from both infected and non-infected host cells. Sufficient infections were carried out to provide triplicate samples for microarray analysis and for q RTPCR analysis. RNA was isolated and hybridised to Affymetrix arrays. Analysis of microarray data identified genes significantly differentially expressed upon infection. Genes were grouped into gene ontology functional categories. Selected genes associated with host glycan structure(glycosyltransferases, hydrolases, lectins, mucins) were validated by real-time q RT-PCR analysis.RESULTS Infection of host cells was confirmed by the isolation of live bacteria after 24 h incubation and by PCR amplification of bacteria-specific genes from the host cell RNA. H. pylori do not survive incubation under the adopted culture conditions unless they associate with the adherent mucus layer of the host cell. Microarray analysis identified a total of 276 genes that were significantly differentially expressed(P < 0.05) upon H. pylori infection and where the fold change in expression was greater than 2. Six of these genes are involved in glycosylation-related processes. Real-time q RT-PCR demonstrated significant downregulation(1.8-fold, P < 0.05) of the mucin MUC20. REG4 was heavily expressed and significantly downregulated(3.1-fold, P < 0.05) upon infection. Gene ontology analysis was consistent with previous studies on H. pylori infection.CONCLUSION Gene expression data suggest that infection with H. pylori causes a decrease in glycan synthesis, resulting in shorter and simpler glycan structures.展开更多
Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex.type oligosaccharide attached to Asn297 of the Fc is essen- tial...Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex.type oligosaccharide attached to Asn297 of the Fc is essen- tial for antibody effector functions, fucose and outer-arm sugars attached to the core heptasaccharide that gen- erate structural heterogeneity （glycoforms） exhibit unique biological activities. Hence, efficient and quan- titative glycan analysis techniques have been increas- ingly important for the development and quality control of therapeutic antibodies, and g｜ycan profiles of the Fc are recognized as critical quality attributes. In the past decade our understanding of the influence of glycosy- lation on the structure/function of IgG-Fc has grown rapidly through X-ray crystallographic and nuclear magnetic resonance studies, which provides possibili- ties for the design of novel antibody therapeutics. Fur- thermore, the chemoenzymatic glycoengineering approach using endoglycosidase-based glycosyn- thases may facilitate the development of homogeneous IgG glycoforms with desirable functionality as next- generation therapeutic antibodies. Thus, the Fc glycans are fertile ground for the improvement of the safety,functionality, and efficacy of therapeutic IgG antibodies in the era of precision medicine.展开更多
The depletion of chondroitin sulfates(CSs)within the intervertebral disc(IVD)during degenerative disc disease(DDD)results in a decrease in tissue hydration,a loss of fluid movement,cell apoptosis,a loss of nerve growt...The depletion of chondroitin sulfates(CSs)within the intervertebral disc(IVD)during degenerative disc disease(DDD)results in a decrease in tissue hydration,a loss of fluid movement,cell apoptosis,a loss of nerve growth inhibition and ultimately,the loss of disc function.To date,little is known with regards to the structure and content of chondroitin sulfates(CSs)during IVD ageing.The behavior of glycosaminoglycans(GAGs),specifically CSs,as well as xylosyltransferase I(XT-I)and glucuronyltransferase I(GT-I),two key enzymes involved in CS synthesis as a primer of glycosaminoglycan(GAG)chain elongation and GAG synthesis in the nucleus pulposus(NP),respectively,were evaluated in a bovine ageing IVD model.Here,we showed significant changes in the composition of GAGs during the disc ageing process(6-month-old,2-year-old and 8-year-old IVDs representing the immature to mature skeleton).The CS quantity and composition of annulus fibrosus(AF)and NP were determined.The expression of both XT-I and GT-I was detected using immunohistochemistry.A significant decrease in GAGs was observed during the ageing process.CSs are affected at both the structural and quantitative levels with important changes in sulfation observed upon maturity,which correlated with a decrease in the expression of both XT-I and GT-I.A progressive switch of the sulfation profile was noted in both NP and AF tissues from 6 months to 8 years.These changes give an appreciation of the potential impact of CSs on the disc biology and the development of therapeutic approaches for disc regeneration and repair.展开更多
基金Supported by Science Foundation Ireland,SFI AGRC Grant,No.08/SRC/B1393
文摘AIM To identify glycosylation-related genes in the HT29 derivative cell line, HT29-MTX-E12, showing differential expression on infection with Helicobacter pylori(H. pylori).METHODS Polarised HT29-MTX-E12 cells were infected for 24 h with H. pylori strain 26695. After infection RNA was isolated from both infected and non-infected host cells. Sufficient infections were carried out to provide triplicate samples for microarray analysis and for q RTPCR analysis. RNA was isolated and hybridised to Affymetrix arrays. Analysis of microarray data identified genes significantly differentially expressed upon infection. Genes were grouped into gene ontology functional categories. Selected genes associated with host glycan structure(glycosyltransferases, hydrolases, lectins, mucins) were validated by real-time q RT-PCR analysis.RESULTS Infection of host cells was confirmed by the isolation of live bacteria after 24 h incubation and by PCR amplification of bacteria-specific genes from the host cell RNA. H. pylori do not survive incubation under the adopted culture conditions unless they associate with the adherent mucus layer of the host cell. Microarray analysis identified a total of 276 genes that were significantly differentially expressed(P < 0.05) upon H. pylori infection and where the fold change in expression was greater than 2. Six of these genes are involved in glycosylation-related processes. Real-time q RT-PCR demonstrated significant downregulation(1.8-fold, P < 0.05) of the mucin MUC20. REG4 was heavily expressed and significantly downregulated(3.1-fold, P < 0.05) upon infection. Gene ontology analysis was consistent with previous studies on H. pylori infection.CONCLUSION Gene expression data suggest that infection with H. pylori causes a decrease in glycan synthesis, resulting in shorter and simpler glycan structures.
文摘Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex.type oligosaccharide attached to Asn297 of the Fc is essen- tial for antibody effector functions, fucose and outer-arm sugars attached to the core heptasaccharide that gen- erate structural heterogeneity （glycoforms） exhibit unique biological activities. Hence, efficient and quan- titative glycan analysis techniques have been increas- ingly important for the development and quality control of therapeutic antibodies, and g｜ycan profiles of the Fc are recognized as critical quality attributes. In the past decade our understanding of the influence of glycosy- lation on the structure/function of IgG-Fc has grown rapidly through X-ray crystallographic and nuclear magnetic resonance studies, which provides possibili- ties for the design of novel antibody therapeutics. Fur- thermore, the chemoenzymatic glycoengineering approach using endoglycosidase-based glycosyn- thases may facilitate the development of homogeneous IgG glycoforms with desirable functionality as next- generation therapeutic antibodies. Thus, the Fc glycans are fertile ground for the improvement of the safety,functionality, and efficacy of therapeutic IgG antibodies in the era of precision medicine.
基金This publication has emanated from research conducted with the financial support of Science Foundation Ireland(SFI)cofunded under the European Regional Development Fund under Grant Number 13/RC/2073.
文摘The depletion of chondroitin sulfates(CSs)within the intervertebral disc(IVD)during degenerative disc disease(DDD)results in a decrease in tissue hydration,a loss of fluid movement,cell apoptosis,a loss of nerve growth inhibition and ultimately,the loss of disc function.To date,little is known with regards to the structure and content of chondroitin sulfates(CSs)during IVD ageing.The behavior of glycosaminoglycans(GAGs),specifically CSs,as well as xylosyltransferase I(XT-I)and glucuronyltransferase I(GT-I),two key enzymes involved in CS synthesis as a primer of glycosaminoglycan(GAG)chain elongation and GAG synthesis in the nucleus pulposus(NP),respectively,were evaluated in a bovine ageing IVD model.Here,we showed significant changes in the composition of GAGs during the disc ageing process(6-month-old,2-year-old and 8-year-old IVDs representing the immature to mature skeleton).The CS quantity and composition of annulus fibrosus(AF)and NP were determined.The expression of both XT-I and GT-I was detected using immunohistochemistry.A significant decrease in GAGs was observed during the ageing process.CSs are affected at both the structural and quantitative levels with important changes in sulfation observed upon maturity,which correlated with a decrease in the expression of both XT-I and GT-I.A progressive switch of the sulfation profile was noted in both NP and AF tissues from 6 months to 8 years.These changes give an appreciation of the potential impact of CSs on the disc biology and the development of therapeutic approaches for disc regeneration and repair.
