title: [In vivo administration of purified supernatant of fetal and postnatal osteoblast cultures: initial results].
abstract: With increasing age of an organism, the osseous regenerative potential is reduced. In osteoblast-like cell cultures, cells of older donors that would not proliferate under standard conditions start to proliferate and express a differentiated phenotype when supplemented with the supernatant of fetal osteoblast-like cultures. The aim of this study was an evaluation of the fetal supernatant actions in vivo. Rat calvaria-derived osteoblasts of fetal and 21-day-old donors were isolated enzymatically and cultured. Their osteoblastic phenotype was confirmed by the expression of typical osteoblast synthesis products. The supernatant of the cultures of each age group was collected and pooled. The supernatant was purified by HPLC and concentrated approximately ten times. Additionally, several age-dependent differences within the purified protein fractions were documented by MALDI. After resuspension, the purified supernatant proteins were transferred on a collagen carrier and implanted into critical size defects of the calvaria of adult Wistar rats. In a control group, the collagen carriers were implanted containing isotonic salt solution. After 2, 4, and 8 weeks, a radiographic and histologic analysis of the regeneration process was performed which revealed differences in the progress of mineralization. The methods used in this study might help to identify age-dependent differences regarding the osteoblastic synthesis of osteoanabolic peptides and their impact on the regeneration of osseous defects.
authors.affiliation: Klinik und Poliklinik für Mund-, Kiefer- und Gesichtschirurgie, Medizinische Hochschule Hannover.
authors.forename: F J
authors.initials: FJ
authors.lastname: Kramer
authors.forename: M
authors.initials: M
authors.lastname: Meyer
authors.forename: H
authors.initials: H
authors.lastname: Schliephake
mesh_terms: D000367:Age Factors; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D005333:Fetus; D010006:Osteoblasts / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000187:drug effects / Q000473:pathology; D014020:Tissue Extracts / Q000494:pharmacology*
chemical_list: D010455:Peptides; D014020:Tissue Extracts