IMMEDIATE RELEASE

Atto Bioscience Signs Agreement to Acquire Cytoprint, Inc.

Acquisition Enables Development of Novel Cell-Based Assays for Drug Discovery

ROCKVILLE, MD - September 10, 2003 - Atto Bioscience, Inc. today announced that it has signed a definitive agreement to acquire Cytoprint, Inc. in a cash and stock transaction projected to close by October 31, 2003. Cytoprint, a privately held corporation based in Santa Fe, New Mexico, develops propriety image analysis technologies that employ statistical analysis of cellular image changes. This technology provides a fundamentally new way of observing, identifying and classifying the response of living cells to pharmacologically active compounds and biologicals in order to increase the speed and reduce the uncertainty of the drug discovery process.

There is a natural fit between Cytoprint's image informatics software and the capabilities of Atto. Cytoprint's software was designed to overcome the limitations to assay development where endpoints may not be clearly decipherable using standard imaging algorithms. The software effectively determines what is important to identify and quantify biological events. Coupling the Cytoprint software to Atto's instrumentation provides a novel approach to high-content biological investigation.

"We are excited to bring this proprietary and proven technology to Atto," said Dr. Derek E. Woods, Atto's President and CEO. "This acquisition broadens Atto's already considerable portfolio of imaging-based tools and reagents applicable to the drug discovery marketplace. It is expected that the technology will be applied to the development of novel cell-based assays for drug discovery and toxicology on Atto's high throughput imaging product, Pathway HT™."

"This merger combines Cytoprint's unique cellular image analysis software with Atto's leading cell imaging technologies, putting enabling assay development and discovery capabilities in the hands of both Pathway HT customers and Atto's scientists," said Dr. John W. Elling, Cytoprint's President and CEO.

About Cytoprint, Inc.

Cytoprint Inc. is developing proprietary image classification technology for fluorescence cellular microscopy. Cytoprint's technology is focused on discovery assays for important biological processes and on linking biological processes to gene and protein function. Similar pattern recognition technologies have been used in the defense industry to decipher satellite images. Founded in 2001 Cytoprint, Inc. is headquartered in Santa Fe, New Mexico.

About Atto Bioscience, Inc.

Atto Bioscience, Inc. is a fully integrated life science company applying proprietary single cell imaging and assay technologies to accelerate pharmaceutical drug discovery/development, toxicology, diagnostics, and functional genomics. Atto brings together several core capabilities including real-time confocal 3D live-cell imaging, kinetic single cell monitoring, software design, novel assay development, automation and manufacturing. Founded in 1985, Atto Bioscience, formerly Atto Instruments, is headquartered in Rockville, Maryland. Additional information is available through www.atto.com or (301) 340-7320.

Media Contact:

Philip G. Vanek
Director, Corporate Development
Atto Bioscience