Protease repertoires of cells adherent to membranes recovered after guided tissue regeneration.

Guided tissue regeneration is a clinical procedure used to restore mineralized tissue that has been lost to periodontal disease or after tooth extraction. The procedure makes use of Gore-tex membranes or Gore-tex augmentation membranes (GTAM) to prevent migration of keratinocytes and gingival fibroblasts into healing wounds. To begin to characterize the regenerative cells associated with these membranes, human cells have been rescued from membranes retrieved after bone-inductive procedures. Cell lines were established from tissue adherent to Gore-tex membranes used to regenerate bone around periodontally compromised teeth, and from tissue adherent to GTAM used in edentulous ridge augmentation procedures or in conjunction with implant placement. Cell lines were screened for mineralized nodule formation in vitro prior to their subsequent analysis. All but one of the lines selected for this study formed mineralized nodules in vitro with cells from GTAM tending to form nodules more quickly than cells from Gore-tex. Zymograms and Western blots were used to compare protease profiles of these cells with those of human gingival fibroblasts, keratinocytes and periodontal ligament (PDL) cells. All cell types except for keratinocytes produced a 72 kD protease. In contrast, keratinocytes were the only cells that produced 92 kD gelatinase. In some cell lines, notably those removed from patients after short periods of regeneration, collagenase was the major protease detected on gelatin substrate gels. Some of these cell lines also produced additional proteases including a low molecular weight protease (30 kD) not seen in gingival fibroblasts, PDL cells or keratinocytes.