Immunofluorescent localization and extractability of fibronectin in human dental pulp.
Fibronectin, visualized in premolar pulps by indirect immunofluorescence, was abundant in the odontoblast layer, around blood vessels and in the core of the pulp. Similarity of alignment of fibronectin with the argyrophilic fibres and von Korff fibres was evident. Fibronectin was extracted from pulps after first removing blood by washing with water, confirmed by eventual negative reaction on alpha 2-macroglobulin. Extraction of fibronectin from this remaining tissue was most effectively achieved by treatment with collagenase or hyaluronidase, though in all cases some fibronectin remained, indicating that fibronectin in pulp is not exclusively associated with collagen and/or proteoglycans. The fibronectin quantified by electro-immunoassay and expressed as percentage of dry weight was 0.030 per cent in the water extract, 0.094 per cent in the collagenase extract and 0.109 per cent in the hyaluronidase extract. Twice as much fibronectin was extracted from the apical pulp as from the coronal and middle parts, in accord with earlier findings of a higher collagen content in the radicular part. It is suggested that with the loss of collagen type III during odontoblast differentiation and its reappearance with advancing vascularization of the dental papilla, the amount of fibronectin is similarly altered.
D000293:Adolescent; D002648:Child; D003782:Dental Pulp / Q000032:analysis*; D005353:Fibronectins / Q000302:isolation & purification*; D005455:Fluorescent Antibody Technique; D006801:Humans; D009804:Odontoblasts / Q000032:analysis
D005353:Fibronectins