At the Future of Regenerative Medicine congress held in New Jersey, attendees were presented with evidence-based research demonstrating the clinical applications of peri-natal tissues, including amniotic membrane, cord blood, cord tissue and placenta. Of particular interest was work presented by Dr Charles S. Cox, a professor of paediatric surgery from the Paediatric Surgical Translational Laboratories and Paediatric Program in Regenerative Medicine at the University of Texas Medical School in Houston, on the repair of cleft palate using Wharton’s jelly.
Cleft lip and palate are common congenital birth defects, typically diagnosed during routine ultrasound examinations around 24 weeks of gestation.
Surgical approaches to repairing cleft defects vary depending on the type of cleft and other health issues. If the cleft extends into the alveolar ridge, which provides structural support for the mid-face and teeth sockets, it is necessary to fill the cleft with a bone graft. Traditionally, surgeons have repaired alveolar cleft palates with a bone graft from the iliac crest of the pelvis. This approach subjects the child to an additional surgical procedure with associated discomfort and risks.
The University of Texas team has developed an approach that uses the supportive tissue of the umbilical cord as a bone graft to augment the repair of alveolar cleft palates. The umbilical cord is a fibrous structure filled with gelatinous tissue that contains mesenchymal stem/stromal cells that support bone growth and can develop into osteoblasts. This supporting tissue of the umbilical cord is called Wharton’s jelly. Even when minced, the collagen fibres in the cord tissue give it structural characteristics that enable it to pack the gap that must be bridged in alveolar cleft palate repair.
As opposed to processing techniques that isolate the stem cells within the umbilical cord via enzymatic digestion of the collagen matrix, they specifically try to preserve the structure of the collagen matrix that is rich in glycosaminoglycan and hyaluronic acid. They have developed unique devices that selectively remove the umbilical blood vessels and the amnion lining to effectively isolate the Wharton’s jelly. The goal was to isolate a tissue product that contains only mesenchymal stem/stromal cells and not epithelial stem cells found in the lining of the blood vessels or the outer lining of the umbilical cord.
A typical surgery for alveolar cleft palate repair requires only 15-20 gm of Wharton’s jelly, which can be obtained from a single umbilical cord. The University of Texas team has conducted multiple pre-clinical studies demonstrating that this approach improves the healing of cleft palate defects in animals. Further studies are being conducted in larger animals as required by the FDA before the approach can be used to treat children with cleft lip and palate and once completed, clinical trials are expected to begin within the next 12-18 months.
At Next Biosciences, Wharton’s jelly is minced and cryopreserved. The tissue can be used in surgical procedures, as described above, and mesenchymal stem cells can be isolated for alternative uses if needed.
References
Future of Regenerative Medicine congress. Presentation by Dr Charles S. Cox: Wharton’s Jelly to Augment Repair of Alveolar Cleft Defects
Parents’ Guide Cord Blood Newsletter, June 2017.