Dendreon and Micra Scientific Team to Provide Cell Separation Products for the Research Marketplace.

MOUNTAIN VIEW, Calif.--(BUSINESS WIRE)--May 13, 1998--Dendreon Corporation (Mountain View, CA) and MICRA Scientific, Inc. (Northbrook, IL) today announced a collaboration aimed at providing life sciences researchers with new products for the simple, reliable and rapid isolation and purification of rare populations of cells. Dendreon has granted MICRA Scientific an exclusive worldwide license to Dendreon's proprietary cell separation technology for use in research markets. Dendreon's technology to separate cells based on buoyant density will be used in combination with MICRA Scientific's proprietary NPS(R) nonporous microspheres. No financial details of the collaboration were disclosed.

The first product launched under the agreement, the MICRA(R) NPS(R) Advanced Cell Trap - Cell Enrichment System (ACT-CES(TM)), allows users to isolate specific rare cells directly from whole blood in a single step with high specificity and minimal processing time using common centrifuges. The product takes advantage of the fine differences in densities that particular cell populations possess, using specific buoyant density solutions and a patented ACT centrifuge tube developed by Dendreon to separate desired lighter cells from unwanted heavier ones. This technique is further enhanced by the addition of dense, antibody-coated MICRA NPS carrier beads to the initial cell mixture, which enable researchers to increase the densities of specifically targeted, light subpopulations of cells to facilitate their removal with unwanted cells after centrifugation.

"We are very pleased to collaborate with MICRA Scientific, a company which has already established a strong presence within the research and chromatography market places," said Dr. Richard Bastiani, president of Dendreon Corporation. "This agreement allows MICRA Scientific to enhance their existing product line and gives our company immediate access to their substantial customer base."

"The simplicity, uniqueness and versatility of the Dendreon technology was a perfect fit with our NPS bead technology for application in the area of cell separations," said Dr. Timothy Barder, co-founder of MICRA Scientific, Inc. "I jumped at the chance for this collaboration because this very elegant technology will allow MICRA to expand its applications for NPS outside of the field of chromatography into other important and fast growing areas of particle-mediated separations."

MICRA Scientific, Inc. has led the effort to introduce high speed-high resolution columns into the chromatography market based on its line of NPS (non-porous silica) HPLC columns. MICRA has developed an extensive base of proprietary technology for the preparation and surface derivitization of highly uniform inorganic spheres with micron and submicron diameters for use in numerous applications.

Dendreon Corporation (formerly Activated Cell Therapy) is a leader in the development of novel cell therapies for the treatment of cancer and infectious disease. The company is a pioneer in the use of dendritic cells to stimulate immune responses and the leading clinical group focused on commercializing dendritic cells for therapeutic purposes. In addition to its dendritic cell therapy programs, Dendreon has developed a complementary line of cell separation products manufactured under GMP which have received regulatory clearance from the FDA. Utilizing proprietary buoyant density centrifugation approaches, the company's devices allow for the enrichment of a wide variety of clinically important blood cells.

CONTACT: Dendreon Corporation

Richard Bastiani, 650/964-6744

or

MICRA Scientific, Inc.

Timothy J. Barder, 847/282-8477