Dendreon identifies novel approach to improve immunization ...( Seattle WA (Nov. 28 2000) Research...)

Seattle, WA (Nov. 28, 2000) Researchers at Dendreon Corporation have reported a novel method for generating an enhanced immune response with potentially important implications for improving the efficiency of therapeutic cancer vaccines. The data, published in the December issue of Nature Biotechnology, highlights a method for modifying targets on cancer cells called antigens to facilitate activation of cytotoxic T cells a key component of the immune system responsible for destroying cancerous cells.

Cancer vaccines are designed to jumpstart the immune systems natural disease-fighting ability. Cytotoxic T-cells in particular have been shown to be directly responsible for killing cancerous cells. Cytotoxic T-cells are educated to detect antigens on cancer cells by dendritic cells immune system watchdogs that internalize and process antigens prior to bringing them to the attention of T-cells.

In their study, Dendreon researchers found that a cytotoxic T-cell response could be greatly enhanced by engineering an antigen in a way that optimizes its uptake and processing by dendritic cells. Their approach involves the addition of a peptidic sequence to a modified, soluble protein antigen. Researchers analyzed the T-cell response elicited by the modified antigen in mouse models and found that mice immunized with the modified antigen generated significant cytotoxic T-cell activity while mice that received unmodified antigen showed no T-cell response.

"Our research provides strong evidence that a robust, enhanced T-cell response can be elicited through this type of antigen engineering. These findings also complement our Antigen Delivery Cassette technology," said Dr. Reiner Laus, lead author of the publication and vice president of immunology at Dendreon Corporation. "This is a novel approach with important implications for the immunotherapy of cancer."

The methodology described in the report is applicable to the development of a variety of vacci
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Contact: Page Sargisson
p.sargisson@noonanrusso.com
415-677-4455 x 229
Noonan/Russo Communications
27-Nov-2000