title: Ethylene glycol and glycerol loading and unloading in porcine meniscal tissue.
abstract: The development of a long-term storage method for meniscus, a complex tissue of the knee prone to injury, would improve the procedure and outcomes of meniscus transplantation. Cryopreservation uses cryoprotective agents (CPAs) including ethylene glycol (EG) and glycerol to preserve a variety of live tissues, and understanding of the CPA permeation kinetics will be critical in designing a vitrification protocol for meniscus. The purpose of this preliminary study was to understand the loading and unloading behaviours of EG and glycerol in meniscus by observing their efflux. For the main experiment, lateral and medial porcine menisci were incubated with CPA for 24 h at three temperatures (i.e., 4, 22, and 37 °C). Then, the menisci were immersed in 25 ml of X-VIVO™10 and CPA efflux was recorded by monitoring the molality of two consecutive washout solutions at different time points. In a subsequent experiment, menisci were incubated in the CPA solutions for 48 h at 22 °C, and the results were compared to those obtained at 22 °C in the main experiment. Results showed a rapid efflux of CPA from meniscus at the beginning of each wash. With increasing temperature, the amount of CPA efflux (and hence loading) increased. Using 24 h incubation, EG loaded the menisci more completely than glycerol. But after 48 h of incubation, both EG and glycerol achieved approximately the same degree of meniscus loading. This study provides preliminary data that will facilitate future design of experiments aimed at development of meniscus permeation studies.
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Alberta, Edmonton, Canada; Rabigh Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Talal A
authors.initials: TA
authors.lastname: Takroni
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Alberta, Edmonton, Canada.
authors.forename: Hana
authors.initials: H
authors.lastname: Yu
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Alberta, Edmonton, Canada.
authors.forename: Leila
authors.initials: L
authors.lastname: Laouar
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Alberta, Edmonton, Canada.
authors.forename: Adetola B
authors.initials: AB
authors.lastname: Adesida
authors.affiliation: Department of Chemical and Material Engineering, University of Alberta, Edmonton, Canada; Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Canada.
authors.forename: Janet A W
authors.initials: JAW
authors.lastname: Elliott
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Alberta, Edmonton, Canada. Electronic address: njmoha@ualberta.ca.
authors.forename: Nadr M
authors.initials: NM
authors.lastname: Jomha
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D019855:Ethylene Glycol / Q000494:pharmacology*; D005990:Glycerol / Q000494:pharmacology*; D008592:Menisci, Tibial / Q000166:cytology / Q000378:metabolism*; D013552:Swine; D058989:Vitrification
chemical_list: D003451:Cryoprotective Agents; D019855:Ethylene Glycol; D005990:Glycerol
keywords: Cryopreservation; Cryoprotectant; Meniscus allograft; Meniscus tissue banking; Permeation; Vitrification