Prof Jonathan Sprent
23 October 2008
While a member of the research faculty at California's Scripps Research Institute, Garvan's Professor Jonathan Sprent collaborated with Professor Charles Surh to develop a novel complex designed to rev up the immune system to fight cancer.
Scripps researchers, including Surh, have now tested the complex in mice for cancer treatment and found it to be effective. The results were published online in the Proceedings of the National Academy of Sciences (PNAS) on October 20.
The complex combines Interleukin-2 (IL-2), a cytokine or chemical messenger, with an IL-2 antibody. IL-2 is well-known for its ability to stimulate the growth of activated T cells - the immune system's killer cells - so is often used to boost immune system response in humans.
Under normal circumstances, the response of T cells to tumour 'antigens' is weak. That's because they see the tumour as 'self', so do not mount an effective attack.
Sprent and Surh's complex boosts the biological activity of IL-2 and so produces a very much more robust T cell response.
The recent Scripps paper demonstrates the ability of the complex to stimulate tumour-reactive T cells, jump starting an immune response by allowing them to grow and ultimately kill tumour cells.
As soon as the complex is removed, the T cells die quickly.
"There are human cancer treatments that use IL-2, but they tend to be highly toxic," says Professor Sprent. "The good thing about our complex is that its effect is around 50 times greater than IL-2 alone. That means, of course, that it can be given in much lower doses to achieve the same effect."
Sprent continues his research into selective stimulation of T cells to target specific cancers. With collaborators in the United States and Switzerland (San Diego and Lausanne), he has founded a company to develop IL-2 antibodies suitable for use in treating patients with cancer.