Geron Corporation has sponsored and licensed the scientific experiments, independently undertaken by competent researchers at two academic institutions, to derive and maintain in culture human pluripotent stem cells for the very first time. This achievement will open unsuspected perspectives for tissue transplantation, drug screening and toxicology testing, as well as for cell and gene therapy. Can newly created immortal cells replace affected cells in the human body to offer us eternal youth?
To unveil the secrets of telomeres and telomerase, which are the biological foundations in cell structures underlying cancer and degenerative diseases, inflicted by old age, forms a major ambition for Geron Corporation. This biopharmaceutical company has been specializing in the research and development of therapeutic and diagnostic products that are based on the buoyant nature of human embryonic stem (hES) cells. Geron's proprietary telomerase technology is focused on prolonging the replicative lifespan of cells derived from hES cells in order to potentially provide indestructible cells for transplantation medicine.
At the Johns Hopkins University School of Medicine, Dr. John D. Gearhart has isolated human embryonic germ (hEG) cells from human foetal tissue whereas Dr. James A. Thomson at the University of Wisconsin, Madison, has successfully derived human embryonic stem (hES) cells from the inner cell mass of donated in vitro fertilized blastocysts. The hEG cells consist of the primordial matter out of which eggs and sperm are formed. These primordial germ cells have been cultured both on feeder layers and in media filled with nutrients and special growth factors to be transformed into pluripotent stem cells.
Pluripotent stem cells are featured with identifiable surface markers, normal chromosome patterns, and replication and differentiation capabilities. As a result, they can develop into virtually any cell or tissue in the human body. In turn, the hES cells present a limitless source of self-renewing cell creation since they are able to produce unrestricted quantities of the various types of cells and tissues, the human physical structure is composed of. In addition, hES cells can be manipulated genetically to optimize their therapeutic value in transplantation medicine to avoid rejection symptoms, which might be provoked by the immune system.
Geron is already planning to generate cardiac muscle cells for the repair of tissue damage caused by heart attack; blood forming cells for patients with cancer who are submitted to bone marrow transplantation; and nerve cells for people suffering from Parkinson's or Alzheimer's disease. Effective drug treatments can be discovered through the engineering of hES cells for the creation of in vivo human disease models instead of using mice. Future hES cell applications also include solutions for infertility, premature pregnancy loss, and prevention of birth defects. A last domain for implementation is the human developmental biology. Fundamental hES research may lead to the discovery of genes controlling the process of tissue differentiation and thus result in the production of new drugs for wound healing, stroke, heart attack and spinal cord injury.
Thanks to the revolutionary advances in cell research by Dr. Gearhart and Dr. Thomson, Geron will be able to enhance innovative techniques to scale up hES cells and identify cell differentiation factors; to genetically engineer the hES cells and produce models for the solid testing of newly proposed transplant products. In the meanwhile, the company is well aware of the ethical implications involved in this kind of biotechnical research and has taken essential measures to improve the patient's life in a responsible way. The November 6 issue of the Science journal has an article on the hES cells' derivation at the University of Wisconsin. A paper on the hEG cell's isolation at Johns Hopkins has appeared in the November 10 issue of Proceedings of the National Academy of Sciences.