Functionally important interactions between heparan sulphate and a variety of proteins depend on the precise location of O-sulphate groups. Such residues occur at C-2 of L-iduronic (IdoA) and D-glucuronic acid (GlcA) units, and at C-3 and C-6 of D-glucosamine (GlcN) units. Stable transfection of human embryonic kidney 293 cells with a cDNA encoding mouse mastocytoma IdoA 2-O-sulphotransferase r...

Proteoglycan biosynthesis by human osteochondrophytic spurs (osteophytes) obtained from osteoarthritic femoral heads at the time of surgical joint replacement was studied under defined culture conditions in vitro. Osteophytes were primarily present in two anatomic locations, marginal and epi-articular. Minced tissue slices were incubated in the presence of [(35)S]sulphate or [(14)C]glucosamine....

High level contamination by natural and industrial sources of the alkali earth metal, barium (Ba) has been identified in the ecosystems/workplaces that are associated with high incidence clustering of multiple sclerosis (MS) and other neurodegenerative diseases such as the transmissible spongiform encephalopathies (TSEs) and amyotrophic lateral sclerosis (ALS). Analyses of ecosystems supporting...

Sulphated glycosaminoglycans, such as heparan sulphate, have been shown to be essential for the infectivity of many organisms. The aims of this study were to verify the role of sulphated glycosaminoglycans in chlamydial infection and to investigate whether they are present on chlamydia or chlamydial host cells. The effect of undersulphation of host cells and chlamydial elementary bodies was exa...

of aortic cells, the pinocytosis proceeded with high efficiency. The uptake remained linear with time for at most 24h and then reached a plateau, probably owing to the competition for uptake by newly secreted unlabelled proteoglycans. A considerable amount of added proteoglycans, however, became associated with the cell surface (pericellular pool of glycosaminoglycans) and are not removed by re...

Heparan sulfate, the polysaccharide side chain of heparan sulfate proteoglycan, is important for the permselective properties of the glomerular basement membrane. In this report, we show a role for hydroxyl radicals in heparan sulfate degradation and an enhanced glomerular basement membrane permeability. First, in enzyme-linked immunosorbent assay, exposure of coated heparan sulfate (proteoglyc...

Rotary shadowing electron microscopy was used to examine complexes formed by incubating combinations of the basement membrane components: type IV collagen, laminin, large heparan sulfate proteoglycan and fibronectin. Complexes were analyzed by length measurement from the globular (COOH) domain of type IV collagen, and by examination of the four arms of laminin and the two arms of fibronectin. T...

Proteoglycans may modulate axon growth in the intact and injured adult mammalian CNS. Here we investigate the distribution and time course of deposition of a range of proteoglycans between 4 and 14 days following unilateral axotomy of the nigrostriatal tract in anaesthetised adult rats. Immunolabelling using a variety of antibodies was used to examine the response of heparan sulphate proteoglyc...

Several processes that occur in the luminal compartments of the tissues are modulated by heparin-like polysaccharides. To identify proteins responsible for the expression of heparan sulfate at the apex of polarized cells, we investigated the polarity of the expression of the cell surface heparan sulfate proteoglycans in CaCo-2 cells. Domain-specific biotinylation of the apical and basolateral m...

This study consists of (1) the extraction of proteoglycan from the human meniscus under dissociative conditions, (2) an investigation of the changes that occur in the abundance and structure of this proteoglycan with age and (3) a comparison of these findings with those for human articular-cartilage proteoglycan. Adult meniscus was found to possess proteoglycan molecules of similar size and gly...