Immunotherapy
Harnessing the Immune System to Treat Disease
Immune Based Therapies
Virax is using novel technology based on discoveries about the workings of the immune system to develop a new generation of medicines to treat widespread, life-threatening diseases.
Immune based therapies or immunotherapeutics work by modifying the response of the body's immune system. This approach recognises the immune system's remarkable ability to defend the body against disease. It uses a similar approach to that traditionally used in preventative vaccines. For this reason immune based therapies are sometimes referred to as therapeutic vaccines, however they are designed to treat existing disease in patients.
Immunotherapy uses biological signals to direct and strengthen, or harness, the body's own immune system. In order to do this, certain naturally occurring biological molecules must be presented to the immune system.
When the body is infected with a disease agent, infected cells change. The immune system is normally triggered by such changes. Immune based therapies are designed to change the course of the immune response initiated by the original disease agent and refocus it to efficiently deal with this agent or disease.
The Immune System
There are two parts to the immune system. In simple terms, one arm of the immune system, using antibodies, attempts to capture and clear the free disease agents circulating in the body; the other arm, using ‘T' cells, attempts to destroy cells that have been invaded or infected with the disease agent.
Antibodies
The immune system detects viruses entering the body and reacts by producing special proteins called antibodies to attack those viruses. Antibodies work by attaching to the surface of the invading virus and ideally stop the infection entering cells where it can replicate itself. Antibodies effectively stop the spread of the infectious agent around the body.
Killer T Cells
The second line of the immune system's defence is called cellular or cell-mediated immunity that comes into play once cells have been penetrated and become infected. Special white blood cells known as killer T-cells seek and destroy infected cells in a cell-mediated response. Killer T cells effectively destroy the "breeding ground" for the infectious agent thereby preventing the infectious agent from increasing its numbers.
As with antibodies, the success of one killer T-cell encourages the production of others via a complex chain of events, which includes the white blood cells signalling through a series of proteins known as cytokines. There is a growing body of experimental evidence to suggest that an appropriate and strong cellular immune response can stop HIV and other viral and intracellular bacterial diseases (eg, TB, leprosy).
With increasing knowledge of molecular biology, scientists have been able to design and construct drugs using living biological vehicles that transport selected genes into targeted cells. Proteins produced from these selected genes then generate a desired response aimed at defeating the disease.
Co-X-GeneTM
Virax's Co-X-GeneTM technology offers a unique immunotherapeutic approach. The Co-X-GeneTM drugs are designed to initiate an immune response to a target protein (antigen) of the disease causing agent and modulate this response to produce the desired outcome of elimination of the disease causing agent. The antigen directs the immune system to cells affected by a particular disease, while the cytokine elicits a specific immune response. The dual action or co-expression of both the cytokine and antigen gene within the human cell to generate the desired disease specific response will potentially give these immune based therapies a competitive advantage.