Effects of Genipin on Decellularized Porcine Cartilage

This research aims to develop an alternative method to osteochondral articular transfer using decellularized, crosslinked porcine osteochondral xenografts (OCXGs). Crosslinking collagenous tissue results in greater mechanical strength, more resistance to enzymatic degradation, and reduced immunogenicity. This study used genipin, a chemical substance from the Gardenia jasminoides Ellis fruit. Genipin is inexpensive and simple to use. In this study, porcine articular cartilage disks were decellularized via a previously published method for porcine nasal septal cartilage decellularization. The process extracts glycosaminoglycan to allow for greater infiltration of nutrients and host cells. The disks were then crosslinked with 0.01% and 0.1% aqueous genipin for 3 days at room temperature with agitation. Prior to decellularization, the cartilage disks’ biphasic properties were determined by confined compression testing. The test was repeated after decellularization and after crosslinking. The aggregate modulus was notably lessened after decellularization but returned to, and in most cases, exceeded that of the fresh disks after crosslinking. Genipin fixation also tended to lower the hydraulic permeability. In a separate experiment, genipin fixation of fresh cartilage was shown to slow the rate of tissue destruction by collagenase. This study demonstrates that genipin seems to be a viable alternative for crosslinking OCXGs.