ROSSLYN, Va., October 14, 1997---Would you rather be stuck with a needle or eat a banana? Biomedical engineers at Cornell University would like you to have that choice when you need a vaccine.
Mark Saltzman, Ph.D., is leading a multidisciplinary team of researchers toward the day when genetically altered, edible plant products form the basis for new vaccines, especially those that prevent sexually transmitted diseases.
Saltzman has received one of six grants that together total more than $5 million for research on technologies to reduce health care costs. The awards were made under a joint program of The Whitaker Foundation and the National Science Foundation entitled Multidisciplinary Research and Education in Cost-Reducing Health Care Technologies. More than $14 million in grants have been made under the program since it began in 1993.
"Oral antigen delivery systems will be important in the next generation of vaccines, particularly for pathogens that enter the body primarily through a mucosal surface, as do most sexually transmitted diseases," Saltzman said.
Vaccines made from animal protein are expensive and time-consuming to produce. Animal proteins must be grown in small laboratory cultures, and, because they are injected directly into the bloodstream, they must be highly purified. All this drives up the cost.
Saltzman wants to lower these costs by concentrating the protein from genetically altered plants into an inexpensive, easy-to-administer pill. This is possible because plants can be grown in large quantities in fields or greenhouses, and oral vaccines do not require the same level of purity as injections.
Once pills are developed, the next step would be to produce plants that contain the right dose of vaccine without further processing. Patients would simply eat a fruit or vegetable.
Saltzman's initial target is sexually transmitted diseases. He has already created the first oral vaccine to protect against chlamydia in mice. Next he will focus on a vaccine pill for hepatitis B, because plant-derived proteins have already been produced for this disease.
The project ties together three established areas of technology: transgenic (genetically altered) plants, in which a human antibody or virus gene is inserted into a plant and allowed to replicate; advanced bioprocessing techniques capable of separating and collecting large quantities of plant protein; and advanced drug delivery systems. In Saltzman's lab, the vaccines are being encapsulated in easily digestible, polymer microspheres.
"All the components are already approved and already part of normal medical care," Saltzman said. "We're just putting them together in a very different way." Saltzman and collaborators Michael Shuler, Ph.D., and Charles Arntzen, Ph.D., hope the research will lead to similar applications for other diseases.
"What we're trying to do is sort of generic. Any immune protein could be put into our delivery system," Saltzman said.
Each year in the United States, 12 million people, including 3 million teenagers, acquire a sexually transmitted disease, and billions of dollars are spent on treatment and prevention. The goal of the joint Whitaker-NSF program is to develop technologies to reduce these and other health care costs. The six new grants under this program are:
Case Western Reserve University, $864,528 from Whitaker
Roger Marchant, Ph.D.
Biosynthetic Surfactants: A Novel Biomimetic Surface to Reduce Intra-Coronary Stent Complications.
Cornell University, $893,597 from NSF
W. Mark Saltzman, Ph.D.
Cost-reducing Protein Production and Delivery Methods for STD Prevention
University of Alabama at Birmingham, $781,553 from Whitaker
Raymond Ideker, M.D., Ph.D.
Catheter Ablation of Cardiac Arrhythmias
University of Kansas Medical Center, $818,133 from NSF
Michael Insana, Ph.D.
New Ultrasonic Techniques for Managing Kidney Disease
University of Utah, $769,328 from Whitaker
Joseph Andrade, Ph.D.
Personal Sensors for the Diagnosis and Management of Metabolic Disorders
University of Wisconsin, $887,270 from NSF
Thomas Grist, M.D.
Reducing Health-Care Costs Using 3D Time-resolved Contrast Enhanced Magnetic Resonance Angiography