Keratan sulfate

About: Keratan sulfate is a research topic. Over the lifetime, 1253 publications have been published within this topic receiving 57984 citations. The topic is also known as: keratan sulfate & KS.

Purification of the keratan sulfate proteoglycan expressed in prostatic secretory cells and its identification as lumican.

Abstract: BACKGROUND. Secretory epithelial cells of human prostate contain a keratan sulfate proteoglycan (KSPG) associated with the prostatic secretory granules (PSGs). The proteoglycan has not been identified, but like the PSGs, it is lost in the early stages of malignant transformation. METHODS. Anion exchange and affinity chromatography were used to purify KSPG from human prostate tissue. Enzymatic deglycosylation was used to remove keratan sulfate (KS). The core protein was isolated using 2D gel electrophoresis, digested in-gel with trypsin, and identified by peptide mass fingerprinting (PMF). RESULTS. The purified proteoglycan was detected as a broad smear on Western blots with an apparent molecular weight of 65-95 kDa. The KS moiety was susceptible to digestion with keratanase 11 and peptide N-glycosidase F defining it as highly sulfated and N-linked to the core protein. The core protein was identified, following deglycosylation and PMF, as lumican and subsequently confirmed by Western blotting using an anti-lumican antibody. CONCLUSIONS. The KSPG associated with PSGs in normal prostate epithelium is lumican. While the role of lumican in extracellular matrix is well established, its function in the prostate secretory process is not known. It's potential to facilitate packaging of polyamines in PSGs, to act as a tumor suppressor and to mark the early stages of malignant transformation warrant further investigation. (C) 2003 Wiley-Liss, Inc.

Serum Sulfotransferase Levels in Patients With Macular Corneal Dystrophy Type I

Abstract: Objective: To measure the levels of sulfotransferase activity for keratan sulfate and chondroitin sulfate in serum of patients with macular corneal dystrophy type I, an inherited disorder that is characterized by the absence of sulfate esters on keratan sulfate in the corneal stroma. Methods: The amount of sulfur-35 transferred from 3′-phosphoadenosine 5′-phosphosulfate to partially sulfated keratan sulfate and partially sulfated chondroitin sulfate by the sulfotransferase present in serum from patients with macular corneal dystrophy and agematched controls was determined under conditions where only the added enzyme was rate limiting. Results: Serum from patients with macular corneal dystrophy type I has the same level of sulfotransferase activity for keratan sulfate and chondroitin sulfate as found in age-matched controls. Conclusions: Patients with macular corneal dystrophy type I have sulfotransferase activity for sulfating at least 1 of the 2 sugars in keratan sulfate. It is proposed that the sulfotransferase for N -acetylglucosamine may be deficient.

Establishment of a monoclonal antibody (1/14/16H9) for detection of equine keratan sulfate.

Abstract: OBJECTIVES: To establish a sensitive and specific monoclonal antibody (MAB) against equine keratan sulfate (KS) and to develop an enzyme immunoassay for measurement of the concentration of KS in serum and synovial fluid from horses. SAMPLE POPULATION: 18 synovial fluid and 48 serum samples were obtained from clinically normal horses and horses with arthritis. PROCEDURE: BALB/c mice were immunized with chondroitinase-ABC-digested proteoglycan monomer from equine joint cartilage, and MAB were raised, using Sp2/O cells as a fusion partner. A competitive ELISA was optimized, using one of the established MAB, and KS concentration in synovial fluid and sera from horses was measured. RESULTS: The high-titer MAB1/14/16H9, which specifically recognizes the epitope on equine KS, was identified. This antibody had no reactivity with chondroitin sulfate and core protein of proteoglycan monomers, hyaluronan, heparin, dermatan sulfate, and heparan sulfate. A competitive ELISA for determination of KS concentration was optimized, using this antibody. Precision data were obtained for the range of 10 to 160 ng/ml. The within- and between-assay coefficients of variation were 10.0 and 12.7%, respectively. CONCLUSIONS: MAB 1/14/16H9 that specifically recognized equine KS was established and was used to develop an enzyme immunoassay for measurement of the concentration of KS in synovial fluid and sera from horses. It is expected that the assay system using MAB 1/14/16H9 will contribute to evaluation of cartilage metabolic activity in horses.

Mapping of Arthritogenic/Autoimmune Epitopes of Cartilage Aggrecans in Proteoglycan-Induced Arthritis

Abstract: Immunization of BALB/c mice with chondroitin sulfate-depleted proteoglycan (aggrecan) of fetal human cartilage produces progressive polyarthritis and ankylosing spondylitis. The development of the disease in genetically susceptible BALB/c mice is dependent upon the expression of both cell-mediated and humoral immune responses against the host mouse cartilage proteoglycan (PG). Although cartilage PGs from various species have many biochemical and immunological similarities, only a select group of PGs from fetal and newborn human, fetal pig and canine articular cartilages, human osteophytes and human chondrosarcomas are able to induce arthritis in BALB/c mice. Arthritis develops only in mice that also develop autoantibodies to self-cartilage PGs, although autoantibodies occasionally are present in non-arthritic animals as well. The protease-sensitive auto/arthritogenic epitope(s) is located in, or close to, the chondroitin sulfate (CS) attachment region of the PG molecule. The primary structure of the core protein is responsible for the autoimmune/arthritogenic effect of this select group of PGs, whereas the core protein epitopes are masked by glycosaminoglycan (GAG)-side chains. The CS side chains seem to inhibit antigen recognition in all aggrecans with arthritogenic potential, whereas a similar effect with keratan sulfate (KS) appears only in PGs of aging cartilages.

67Ga accumulation in inflammatory lesion and its mechanism: Comparison with malignant tumor

Abstract: The accumulation of 67Ga in inflammatory lesions increased with time after injection of turpentine iol and reached a plateau 5 days later. At that time the uptake in the lesions was larger than any other tissue, after ten days the lesion uptake decreased. In experiments using rats which had been kept for 5 days after subcutaneous injection of turpentine oil, the accumulation of 67Ga in inflammatory lesions increased with time until six days after administration of 67Ga-citrate. It is clear from this study that 67Ga is avidly accumulated in areas where the subcutanous tissue is infiltrated with neutrophils and macrophages, that it is not accumulated at the sites in which neutrophils are crowded, that nuclear material, mitochondria, lysosomes and microsomes do not play a major role in 67Ga accumulation in the lesion and that the main binding acid mucopolysaccharide in the lesion is acid mucopolysaccharide which is none of the following: keratan sulfate, heparan sulfate, heparin, or chondroitin sulfate A, B or C. It is presumed that the main 67Ga binding acid mucopolysaccharide is keratan polysulfate (or other oversulfated acid mucopolysaccharides).