O121: Advancing Surgical Innovations: A Novel Approach to Engineering an Off-The-Shelf Bone-Tendon Junction Scaffold Suitable for Transplantation

Abstract

Abstract Background Musculoskeletal injuries occurring at a staggering rate of 1.7 billion annually, frequently involve the complex bone-tendon junction (BTJ) often due to tear from tendon end due to cyclical strain. Current treatment options, varying from repair to reconstruction usually result in suboptimal outcomes due to structural inconsistencies. Methods In this novel study, we developed comprehensive approach to tackle this clinical challenge. We subjected BTJ tissue harvested from rabbit lower limbs (N=22) to decellularisation process. This involved 5-day demineralisation with 5% formic acid, followed by 8-day proprietary decellularisation method. Further, decellularised bone segments were immersed in Ca-P simulated body fluid for 24 hours to achieve mineral phase and enhance cell attachment. To facilitate recellularisation, adipose-derived stem cells were cultured in differentiating media for 14 days, differentiating into osteoblasts and fibroblasts for bone and tendon segments respectively. Cell phenotype was characterised using cell identification assays. Precise injection of differentiated cells into respective segments was conducted under cyclical mechanical loading with innovative stepper motor device, simulating native tissue physiology. Results Confirmation of effective decellularisation was established through histological characterisation and DNA quantification, with DNA content reduced to <50ng/mg (p<0.05) in bone segment. Successful recellularisation of decellularised scaffold and cell alignment in direction of mechanical load was confirmed through histological analysis on day 5. Comparative analysis revealed similarities in properties between control, remineralised, and recellularised bone, presenting this approach as a promising regenerative technique. Conclusion Our approach offers hope to potentially revolutionise clinical outcomes in this challenging domain by effectively replicating native tissue properties.