Improving Culture Conditions for Temporomandibular Joint Disc Tissue Engineering

Background: The temporomandibular joint (TMJ)is ex-tremely important for activities like eating and talking, which can become painful and difficult for patients with TMJ dys-function. Tissue engineering is a potential alternative to cur-rent surgical interventions through replacement of diseased or injured tissue with a functional construct. Since research with TMJ disc cells began relatively recently, optimal cultur-ing conditions must be determined. Methods: Metabolic additives, L -glutamine, L -alanyl-L -glutamine, sodium pyru-vate, and insulin, were examined for their effects on TMJ disc cells in monolayer. Effects of L -proline were examined in three-dimensional (3-D)culture at concentrations of 0, 25 and 100 mg/l. Results: The combination of L -glutamine, so-dium pyruvate, and insulin improved cell proliferation rates without affecting collagen production or gene expression. No differences were observed in mechanical properties of the engineered constructs; however, collagen and glycos-aminoglycan quantities normalized to cell number de-creased at the highest concentration of L -proline. Conclu-sion: This work identified supplements for 2-D monolayer expansion. Other supplements or culture conditions still need to be investigated for 3-D tissue production. This work improves upon porcine TMJ disc cell culturing conditions, taking us closer to being able to engineer the TMJ disc.