BioSource International, Inc. Launches Industry's First p38 MAPK ELISA Assay.

Business Editors & Health/Medical Writers

CAMARILLO, Calif.--(BUSINESS WIRE)--April 4, 2002

BioSource has launched a unique immunoassay to detect and quantify levels of p38 MAPK; an important protein in drug discovery research focused on mitogen activated protein kinases (MAPK). This immunoassay detects and quantifies levels of phosphorylated p38 MAPK (pTpY 180/182) -- the activated form of this important protein.

"I am pleased we are able to launch the p38 MAPK kit at this time, just prior to the American Association of Cancer Research meeting in San Francisco next week," noted Len Hendrickson, President and CEO of BioSource International, Inc. "The exciting aspect of this product is its importance to drug discovery research, not only for cancer, but also for additional key disease targets."

Many pharmaceutical companies are studying p38 MAPK modifiers as drug candidates in a wide variety of diseases including several types of cancer, Parkinson's Disease, diabetes, and cardiovascular disease. BioSource's new p38 MAPK ELISA kit is directly targeted at applications for these areas of research.

"In February, we announced that BioSource would increase its research and development expenditures and focus on signal transduction and advanced assay development," continued Mr. Hendrickson. "This strategy has allowed us to invest in the reagent development that was critical to the launch of this kit. We anticipate the release of other phosphorylation state specific immunoassays in the near future to capitalize on the need for fast, sensitive assays in the rapidly growing area of signal transduction research.

"Further, we have filed for intellectual property for phospho-specific ELISAs and, if granted, these patents will create a superior and sustainable competitive position for BioSource in this market."

Designed as a replacement for traditional kinase assays that utilize peptide substrates, the p38 MAPK ELISA kit is part of the expanding family of BioSource Signal Transduction ELISAs which are faster, more sensitive and more reproducible than Western blotting techniques for verifying the presence of activated protein.

In addition to the p38 MAPK (pTpY108/182) kit, BioSource offers other phospho-specific ELISAs including three phosphorylation sites for Tau protein, one for Rb protein, and two sites for EGFR. BioSource also offers total protein assays for Tau, Rb, EGFR and p38 MAPK.

BioSource International, Inc. is a broad based life sciences company focused on providing integrated solutions in the areas of functional genomics, proteomics, and drug discovery through the development, manufacturing, marketing and distribution of unique biologically active reagent systems which facilitate, enable and accelerate pharmaceutical development and biomedical research.

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