title: A human periodontal ligament fibroblast clone releases a bone resorption inhibition factor in vitro.
abstract: The conditioned media (CM) obtained from three lines of cloned human periodontal ligament (PDL) cells were analyzed to determine whether they altered the parathyroid hormone (PTH)-stimulated resorption rates (45Ca release) in 48-hour cultures of 45Ca-labeled rat long bones. One PDL cell line, PDL-5, produced a heat-resistant factor in its CM that inhibited the PTH-stimulated resorption by 43.8 +/- 9.7 (SE) percent (p less than or equal to 0.02), whereas the CM from the other cell lines were without statistically significant effect. The CM from the PDL-5 line did not diminish organ culture viability, as determined by 3H-thymidine incorporation, and did not enhance or diminish the resorption-inhibiting activity of calcitonin added to the PTH-stimulated cultures. The addition of CM from PDL-5 did not alter the bone-resorbing effect of interleukin-1 (IL-1). These results indicate that CM from PDL-5 inhibits only the PTH-induced and not the IL-1-mediated resorption processes, whose mechanisms are therefore likely to differ.
authors.affiliation: Department of BioStructure and Function, University of Connecticut Health Center, Farmington 06030.
authors.forename: M S
authors.initials: MS
authors.lastname: Giniger
authors.forename: L
authors.initials: L
authors.lastname: Norton
authors.forename: S
authors.initials: S
authors.lastname: Sousa
authors.forename: J A
authors.initials: JA
authors.lastname: Lorenzo
authors.forename: F
authors.initials: F
authors.lastname: Bronner
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001862:Bone Resorption; D001842:Bone and Bones / Q000378:metabolism; D002116:Calcitonin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D003470:Culture Media; D004247:DNA / Q000096:biosynthesis; D005347:Fibroblasts / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D009924:Organ Culture Techniques; D010010:Osteoclasts / Q000187:drug effects; D010281:Parathyroid Hormone / Q000494:pharmacology; D010513:Periodontal Ligament / Q000737:chemistry / Q000166:cytology* / Q000502:physiology*; D051381:Rats
chemical_list: D003470:Culture Media; D007375:Interleukin-1; D010281:Parathyroid Hormone; D002116:Calcitonin; D004247:DNA; D002118:Calcium