title: Development of an intact intervertebral disc organ culture system in which degeneration can be induced as a prelude to studying repair potential.
abstract: The present work describes a novel bovine disc organ culture system with long-term maintenance of cell viability, in which degenerative changes can be induced as a prelude to studying repair. Discs were isolated with three different techniques: without endplates (NEP), with bony endplates (BEP) and with intact cartilage endplates (CEP). Swelling, deformation, and cell viability were evaluated in unloaded cultures. Degeneration was induced by a single trypsin injection into the center of the disc and the effect on cell viability and matrix degradation was followed. Trypsin-treated discs were exposed to TGFβ to evaluate the potential to study repair in this system. NEP isolated discs showed >75% maintained cell viability for up to 10 days but were severely deformed, BEP discs on the other hand maintained morphology but failed to retain cell viability having only 27% viable cells after 10 days. In CEP discs, both cell viability and morphology were maintained for at least 4 weeks where >75% of the cells were still viable. To mimic proteoglycan loss during disc degeneration, a single trypsin injection was administered to the center of the disc. This resulted in 60% loss of aggrecan, after 7 days, without affecting cell viability. When TGFβ was injected to validate that the system can be used to study a repair response following injection of a bio-active substance, proteoglycan synthesis nearly doubled compared to baseline synthesis. Trypsin-treated bovine CEP discs therefore provide a model system for studying repair of the degenerate disc, as morphology, cell viability and responsiveness to bio-active substances were maintained.
authors.affiliation: Orthopaedic Research Laboratory, McGill University, 687 Pine Avenue West, Room L4.70, Montreal, QC H3A 1A1, Canada.
authors.forename: Bernice
authors.initials: B
authors.lastname: Jim
authors.forename: Thomas
authors.initials: T
authors.lastname: Steffen
authors.forename: Janet
authors.initials: J
authors.lastname: Moir
authors.forename: Peter
authors.initials: P
authors.lastname: Roughley
authors.forename: Lisbet
authors.initials: L
authors.lastname: Haglund
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000473:pathology / Q000502:physiology / Q000601:surgery; D002417:Cattle; D002470:Cell Survival / Q000502:physiology; D007403:Intervertebral Disc / Q000473:pathology / Q000502:physiology* / Q000601:surgery*; D055959:Intervertebral Disc Degeneration / Q000139:chemically induced / Q000473:pathology* / Q000601:surgery*; D008297:Male; D009924:Organ Culture Techniques / Q000379:methods*; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D014357:Trypsin