What is an Immunotherapy Vaccine?
The immune system is the body's defense mechanism responsible for recognizing and eliminating cancer cells, viruses, bacteria, and other disease-causing organisms. Dendritic cells are the "scouts" of the human immune system that act as the guidance mechanism for the body's immune defenses. These specialized scout cells travel through the blood stream looking for whatever infections or diseases they can find. When they discover an intruder, these scout cells capture data on the infection or disease and instruct the body's killer T-cells to attack it.
Relatively higher concentration levels of tumor-specific killer T-cells within a patient's tumor appear to be linked with improved patient outcome. The problem is that this natural self-defense effort mounted by the human immune system is typically not delivered with sufficient force to combat cancer cell production. The immune system appears to deploy the correct soldiers for the fight, but it deploys a woefully inadequate number of them. Approximately only one-half of one percent of an ovarian cancer patient's killer T-cells are programmed to attack the tumor, unless the immune system is instructed to take more aggressive action.
Immunotherapeutic vaccines seek to increase the immune system's attack on the patient's cancer by intensifying the same interaction between scout cells and killer cells that occurs in nature. George Coukos, MD, PhD, director of the Penn Ovarian Cancer Research Center states, "The dendritic-cell vaccine that Penn is supporting takes the natural attack function of the immune system and amplifies it, thereby focusing a much higher percentage of the patient's immune system on her ovarian cancer. The ultimate objective of these cancer vaccines is to direct a larger percentage of the patient's killer T-cell army against the patient's specific cancer."
Making a "Natural" Vaccine
The ovarian cancer vaccine that Penn is currently testing via clinical trials is an "autologous" vaccine. Autologous vaccines represent one of the most natural of all vaccine designs because their major components are derived directly from the patient. Autologous vaccines use the patient's own tumor tissue is to educate and direct the patient's own dendritic cells which, in turn, deploy more of the patient's own tumor-specific killer T-cells to attack the cancer.
Is This Vaccine Safe?
Safety is typically not an issue with an autologous vaccine because it is based on the patient's own cells and tissue rather than antigens or other material that is not naturally-occurring. A red, itchy injection site is the most typical adverse reaction. No nausea, no debilitating fatigue, no hair loss, etc. This experience mirrors the typical toxicity symptoms of other institutions using or testing therapies based upon autologous components.
Related Research Initiatives
The mission of Penn's ovarian cancer vaccine initiative is to finance the vaccine trial described above. However, if available funds permit, our program would also provide research support to The Abramson Cancer Institute which specifically seeks to improve or expand the applicability of this ovarian cancer vaccine.
For more information about the ovarian cancer vaccine trials, to make an appointment with a Penn gynecologic oncologist or to make a donation to Penn's ovarian cancer research efforts call 800-789-PENN (7366).
Research Update: A Vaccine to Attack Ovarian Cancer
Penn researchers use patient's own tumor tissue and create an immunotherapy vaccine to attack ovarian cancer.