Gene therapy, biologics expand treatment options for spine patients

Nov. 18, 2005
Breakthrough treatment advances could mean noninvasive relief.

The Spine JournalT (TSJT), the official journal of the North American Spine Society (NASS), released a special issue this November showcasing the latest research in the areas of spine biologics and bioactive materials -- what many researchers are calling the future of spine surgery.

The issue is the brainchild of Drs. Howard An and Frank M. Phillips of Rush University Medical Center in Chicago.

Howard An, MD, an orthopedic surgeon at Rush University Medical Center
in Chicago, is the editor of the "Spine Biologic and Bioactive Materials" special issue. The use of biologic material has been one of the most exciting developments in spine care and continued research will bring many of these projects into the market place in spine care," says Dr. An.

Multidisciplinary spine care has come a long way in offering relief for patients suffering from spine disease or injury, and even providing relief from the natural process of degeneration that tends to come with aging.

Spine researchers are investigating a new type of spine treatment options called "spine biologics" that work with the body's natural processes to assist in healing after surgery or to provide alternative products that can be implanted to mimic the normal function of diseased or degenerated spine components.

These new technologies in development focus on two primary areas for the
spine: therapies to assist healing for patients who undergo a spine fusion procedure, and treatments for patients who have injured or diseased intervertebral discs (the cushions between the vertebra that allow movement.)

Some of the most exciting work is in the area of gene therapy. This involves using a "therapeutic molecule" ¿ a carrier that delivers genetic information to a targeted site. Viruses have been harnessed for the job of carrier because of their ability to integrate their genomes into the chromosomes of cells to which they are directed.

Growth factors have been identified that can stimulate bone growth necessary to healing after fusion surgery. (Formerly, bone graft was used to fuse the bones but the risks with autograft are pain and infection at the site of the bone harvest, often the hip, and allograft can be rejected.)

Viruses can be used to deliver these growth factors to the right area of the spine. Research is still being done to identify ways to inhibit disc degeneration, or even to encourage cells to repair themselves. These possibilities are on the horizon of scientific development.

However, there are still dangers associated with gene therapy; altering the genetic material risks mutation or even the development of cancerous cells. Research is ongoing to tightly control the action of the therapeutic molecule and limit its area and time of effectiveness.

Right now, some forms of bone morphogenetic protein (growth stimulators) are FDA approved for use in long bones and animal studies have been done for use in the spine. Once the process has been fine-tuned, gene therapy
offers the promise of easy access, higher success rates and lower cost than currently available technologies, with fewer complications for the patient.

The 130-page-supplement contains 14 original research papers covering
three main uses of biologics: Spinal Fusion, Disc Regeneration and
Kyphoplasty and Nucleus Pulposus Prosthesis. Below is a listing of the
featured papers:

Spinal Fusion
Biologics in Spinal Surgery: Introduction and Overview
Animal Models for Spinal Fusion
Demineralized Bone Matrix for Spinal Fusion
Carrier Materials for Spinal Fusion
Cell Technologies for Spinal Fusion
Bone Morphogenic Proteins (BMPs) for Spinal Fusion
Gene Therapy for Spinal Fusion
Disc Regeneration
Molecular Pathogenic Factors in Degenerative Disc Disease
Animal Models for Disc Repair
Molecular Therapy of the Intervertebral Disc
Gene Therapy for Disc Repair
Cell-based Therapy for Disc Repair
Kyphoplasty & Nucleus Pulposus Prosthesis
Vertebroplasty and Kyphoplasty - Filler Materials
Nucleus Pulposus Replacement - An Emerging Technology

To obtain a copy of the "Spine Biologics and Bioactive Materials" supplement of The Spine JournalT, to schedule an interview with any of the participating authors or for any additional information, please contact Deanna Marchetti at [email protected], or by phone at (708) 588-8081.