Scripps Health Receives $12.7 Million Grant to Develop Scaffold-Free Stem Cell Therapy for Knee Cartilage Repair
Key Insights
Scripps Health received a $12.7 million grant from the California Institute of Regenerative Medicine (search) to investigate scaffold-free stem cell therapy for repairing knee cartilage injuries larger than 2 square centimeters.
The research will use three-dimensional cellular spheroids made from mesenchymal stem cells that fuse together to form transplantable cartilage tissue, avoiding limitations of traditional scaffold-based approaches.
The five-year preclinical study aims to demonstrate safety and effectiveness in animal models, with plans to submit a new drug application to the FDA for potential human clinical trials.
Scripps Health has been awarded a $12.7 million grant from the California Institute of Regenerative Medicine (search) to advance groundbreaking research into scaffold-free stem cell therapy for knee cartilage repair. The five-year funding will support preclinical studies investigating whether laboratory-grown cartilage tissue can effectively treat knee injuries and potentially eliminate the need for joint replacement surgeries.
Revolutionary Approach to Cartilage Regeneration
The research, led by Dr. Darryl D'Lima, director of orthopedic research at Scripps Health, focuses on a novel technique that uses three-dimensional cellular spheroids to regenerate damaged cartilage. Unlike traditional methods that have struggled for decades using artificial scaffolding, this approach allows stem cells to build their own connections naturally.
"For the past 30 years, we've been building scaffolds and putting cells in those scaffolds, saying, you know, maybe they'll grow, but it has been a little like putting together grass seeds and astroturf," D'Lima explained. The new method creates tiny "microspheroids" containing between 10,000 and 20,000 cells that can fuse together to form larger pieces of cartilage.
Senior staff scientist Shawn Grogan at the Shiley Center for Orthopaedic Research (search) developed the technology to generate scaffold-free cartilage and bone tissue using mesenchymal stem cells. When these lab-grown tissues were implanted into osteoarthritic tissue samples, they effectively repaired defects and structurally integrated with the injured tissues.
Addressing Significant Medical Need
Cartilage injuries of the knee affect approximately 900,000 people annually in the United States, resulting in more than 200,000 surgical procedures, according to Clinical Orthopaedics and Related Research. The Scripps research specifically targets larger knee injuries where damage to cartilage and underlying bone exceeds 2 square centimeters.
Current treatment options include osteochondral allograft transplant surgery, which involves replacing damaged tissue with healthy cartilage and bone from deceased donors. However, this approach faces significant limitations including limited availability of donor tissue and preservation challenges. Another option uses the patient's own cartilage cells but requires two separate surgeries and involves cells that are not ideal for regrowing cartilage due to slow growth and poor metabolism.
Clinical Promise and Future Applications
The scaffold-free approach offers several advantages over conventional methods. "Scaffold-free tissue closely mimics cells in developing native tissue and have high potential for healing," according to Scripps researchers. The technique avoids limitations associated with scaffolds, such as poor integration and compatibility with host tissue.
D'Lima noted that an initial Scripps trial harvesting stem cells from patients and re-injecting them into joints showed promising results, with approximately 40% of patients who initially needed knee replacements avoiding surgery. However, he cautioned that this could represent a placebo effect since the trial was not placebo-controlled.
The preclinical work will focus on demonstrating that spheroid-based cartilage colonies can be successfully transplanted into damaged areas in animal models without triggering rejection or other negative side effects. At the end of the five-year grant period, researchers plan to submit a new drug or biological product application with the Food and Drug Administration.
Broader Impact on Joint Health
"A biological implant that can successfully treat cartilage and bone defects of the knee would resolve the limited availability of donor graft tissue and has the potential to delay and eventually eliminate the need for joint replacement," D'Lima stated. The approach could also be applicable to other joints including the ankle, elbow, shoulder, and hip.
Treating these injuries early could prevent progression to osteoarthritis, the debilitating condition that occurs when cartilage wears away, causing severe pain and inflammation in joints. The research builds on work already performed by the Shiley Center for Orthopaedic Research (search) at Scripps Clinic and represents a significant step toward developing regenerative therapies for joint preservation.
The funding comes from California's regenerative medicine institute, established in 2004 when voters approved Proposition 71 to provide $3 billion for stem cell research at a time when many states were blocking such research due to religious concerns.