Symposium: Allograft Research and Transplantation 9 articles
GNAS1 and PHD2 Short-interfering RNA Support Bone Regeneration in Vitro and in an in Vivo Sheep Model
Our ability to guide cells in biomaterials for in vivo bone repair is limited and requires novel strategies. Short-interfering RNA (siRNA) allows the regulation of multiple cellular pathways. Core binding factor alpha 1 (Cbfa1) and hypoxia-inducible factor 1 (HIF-1) pathways can be modulated to direct bone formation via siRNA against guanine nucleotide-binding protein alpha-stimulating activity polypeptide 1 (siGNAS1) and prolyl hydroxylase domain-containing protein 2 (siPHD2), respectively.
Bone marrow plays a key role in bone formation and healing. Although a subset of marrow explants ossifies in vitro without excipient osteoinductive factors, some explants do not undergo ossification. The disparity of outcome suggests a significant heterogeneity in marrow tissue in terms of its capacity to undergo osteogenesis.
Remodeling of structural bone allografts relies on adequate revascularization, which can theoretically be induced by surgical revascularization. We developed a new orthotopic animal model to determine the technical feasibility of axial arteriovenous bundle implantation and resultant angiogenesis.
Surface Treatment of Flexor Tendon Autograft and Allograft Decreases Adhesion Without an Effect of Graft Cellularity: A Pilot Study
Flexor tendon grafting is often required to reconstruct a failed tendon repair. Previous reports have demonstrated flexor grafts coated with lubricants such as carbodiimide derivatized hyaluronic acid (cd-HA) decrease adhesion formation and improve digit function. However, whether this surface modification would affect graft adhesion and cellularity is unknown.
Stem cell mobilization, which is defined as the forced egress of stem cells from the bone marrow to the peripheral blood (PB) using chemokine receptor agonists, is an emerging concept for enhancing tissue regeneration. However, the effect of stem cell mobilization by a single injection of the C-X-C chemokine receptor type 4 (CXCR4) antagonist AMD3100 on intramembranous bone regeneration is unclear.
Allograft integration in segmental osseous defects is unpredictable. Imaging techniques have not been applied to investigate angiogenesis and bone formation during allograft healing in a large-animal model.
Scaffold devices are used to augment rotator cuff repairs in humans. While the strength of a novel poly-L-lactic acid-reinforced (human) fascia patch has been documented, it is unclear whether such patches will enhance the strength or likelihood of healing of rotator cuff repairs.
Gamma radiation sterilization can make cortical bone allograft more brittle, but whether it influences mechanical properties and propensity to form microscopic cracks in structurally intact cancellous bone allograft is unknown.