Nino Sorgente

Proteinase inhibitor activity in connective tissues

Extrakte verschiedener Bindegewebe wurden auf ihre Proteasehemmung hin elektrophoretisch untersucht. Alle Gewebe zeigten kationisch wandernde Aktivität und ihre Anwesenheit im zellfreien Dentin lässt den Schluss zu, dass das Material extrazellulär lokalisiert ist.

Lysozyme in preosseous cartilage VII. Evidence for physiological role of losozyme in normal endochondral calcification

Abstract Previous work demonstrated that micropuncture aspirates from rat epiphysical plate cartilage contain a nucleating agent for Ca 3 (PO 4 ) 2 mineral growth, and that the nucleation is inhibited by proteoglycan aggregates. In this report data are described which show that mammalian lysozyme inactivates the inhibition. When micropuncture aspirates are incubated in vitro with mammalian lysozyme, a rapid, spontaneous initiation of mineral growth occurs. Incubation of proteoglycan aggregate preparations in the presence of cartilagea lysozyme, but not hen egg white lysozyme, causes a marked decrease of the sedimentation coefficients of the proteoglycans, usually to values close to those obtained with proteoglycan monomer preparations. The inhibition of this effect of mammalian lysozyme by a specific inhibitor of the enzyme tri( N -acetyl-D-glucosamine) suggests that it may be enzymatic in nature.

Lysozyme in preosseous cartilage VI. Purification, characterization and localization of mammalian cartilage lysozyme

Abstract Lysozyme (mucopeptide- N -acetylmuramylhydrolase, EC 3.2.1.17) is present in mammalian cartilage. Lysozyme was isolated and purified from bovine and canine cartilage and from dog serum using various chromatographic steps and affinity chromatography on carboxymethylated chitin. Amino acid analysis of bovine cartilage lysozyme showed that it is similar to other mammalian lysozymes. Anti-canine lysozyme antibodies cross-react with calf lysozyme, but not with hen egg white or embryonic chick cartilage lysozyme. In the epiphyseal plate of the dog, 90-μm sections were analyzed for lysozyme and its was found that in the hypertrophic zone its concentration is approximately six times higher than it is in the resting zone. Using immunocytochemical techniques at the electromicroscopic level, lysozyme in the epiphyseal plate of the dog was localized extracellularly, mainly in the immediate vicinity of the chondrocytes, the territorial matrix.