Arterial chondroitin sulfate proteoglycan: localization with a monoclonal antibody.

Abstract

We generated a monoclonal antibody (Mab) against a large chondroitin sulfate proteoglycan (CSPG) isolated from bovine aorta. This Mab (941) immunoprecipitates a CSPG synthesized by cultured monkey arterial smooth muscle cells. The immunoprecipitated CSPG is totally susceptible to chondroitinase ABC digestion and possesses a core glycoprotein of Mr approximately 400-500 KD. By use of immunofluorescence light microscopy and immunogold electron microscopy, the PG recognized by this Mab was shown to be deposited in the extracellular matrix of monkey arterial smooth muscle cell cultures in clusters which were not part of other fibrous matrix components and not associated with the cell's plasma membrane. With similar immunolocalization techniques, the CSPG antigen was found enriched in the intima and present in the medial portions of normal blood vessels, as well as in the interstitial matrix of thickened intimal lesions of atherosclerotic vessels. Immunoelectron microscopy revealed that this CSPG was confined principally to the space within the extracellular matrix not occupied by other matrix components, such as collagen and elastic fibers. These results indicate that this particular proteoglycan has a specific but restricted distribution in the extracellular matrix of arterial tissue.

Cell biology of arterial proteoglycans.

“…However, the relative amounts of aortic chondroitin sulfate increased, and dermatan sulfate decreased in the hypercholesterolemic animals, indicating that cholesterol feeding may influence the types of proteoglycans that accumulate but not the total quantity. Intense immunostaining using an antj-aortjc CSPG antiserum, has been observed in atherosclerotic lesions in the rabbit after lipkJ feeding 15 ( Figure 3). The mechanism responsible for this specific accumulation is unclear, but it may be that lipoproteins influence the synthesis of proteoglycans by the resident cells of the arterial wall.…”

“…Immunocytochemical studies reveal that a large CSPG is restricted to the interstitial matrix of arterial smooth muscle cell cultures and blood vessels and is not part of other matrix components such as collagen, elastic fibers, and basal laminae 15 ( Figure 3). However, a smaller CSPG that has hydrophobic properties and is immunologically distinct from the large interstitial CSPG is present in nonhuman primate arterial smooth muscle cell cultures and may be associated with the plasma membrane of these cells.…”

Heterotopic bone formation in tumor stromal tissue. Immunohistochemical considerations.

“…With regard to ossification and matrix formation, proteoglycans and bone sialoprotein accumulation might be one of the important factors in initial mineralization (13,18,23). Bone matrix is composed of proteoglycans (PGs), such as chondroitin sulfate PG (CSPG), dermatan sulfate PG (DSPG), heparan sulfate PG (HSPG), and keratan sulfate PG (KSPG) (5), and they are also contained in blood vessel walls, and smooth muscles (4,17,18), cartilage matrix (81, 23 , 24), and so on (7,13). Identification of these PGs has already been described immunohistochemically by the use of specific monoclonal antibodies accompanied with enzymatic digestion (5).…”

Glycosaminoglycan Distribution in Chondro-Osteogenesis Induced by Bone Morphogenetic Protein in Mouse Muscle Tissue with the Use of Monoclonal Antibodies.

“…Classic histochemical observations on proteoglycans (PGs) or GAGs have been made using alcian blue stainings in combination with specific enzyme digestions (5,9), and monoclonal antibodies (MoAbs) specific for epitope(s) of GAGs combined with enzyme digestion techniques have recently been in general employed as well (2,4,17,19,22,23,26,28,29). These investigations have provided significant supplemental information to previously identified PGs and GAGs by biochemical evaluations.…”

“…The structures, functions, and biological significance of GAGs have widely been reviewed in that CS is usually contained in cartilage tissues and blood vessel walls, DS in tendon and skin, heparan sulfate in the cell surface and basement membrane, and KS in the corneal stroma (10). In arterial tissues, CS was identified as a primary structural component (17); however, KS was identified as a major component of the atherosclerotic lesion of the aortas in pigeons (25). In mammals, KS has been reported as a major component of the cornea matrix and of cartilage tissues biochemically (9).…”