Press Release

Cellectis S.A. and Celliance^TM, a Serologicals Company, enter in collaboration for mammalian cell lines engineering for production purposes.

Romainville, France and Atlanta, USA - May the 31^st, 2005 - Cellectis S.A., the rational genome engineering company, and Celliance^TM, a Serologicals Company (Nasdaq: SERO), announced today that they entered into a collaboration agreement under which Celliance^TM will evaluate the Meganuclease Recombination System (MRS) technology of Cellectis for the development of a new generation of I-SceI meganuclease tagged host cell line, the generation and the promotion of efficient derivative cell lines for biopharmaceutical production.
Financial terms and conditions were not disclosed.

Isabelle Pelletier-Bressac, Vice President Business Development of Cellectis commented "We do have several other evaluations going on with both CMOs and therapeutic proteins developers and we are very pleased of this new agreement with Celliance. Supported by strong internal results on meganuclease induced gene knock-in in CHO cells, we are convinced that the expertise and skills of Celliance. scientists relating to culture, development and use of host cell lines suitable for cellular protein production will lead to successful results". She added, "Indeed, in mammalian cells, the major advantages of our site-directed insertion system is a better control in the generation of producer cell lines, i.e. reproducibility, predictability, and consequently a gain of time in manufacturing."

Cellectis SA (www.cellectis.com) was founded in 1999, as a spin-off from the Institut Pasteur. Today, Cellectis is the world leader in applying the technology of Meganuclease Recombination Systems to in vivo genome engineering and genome surgery. The company is focused on the research and development of custom-made Meganucleases for in vivo DNA interventions and also provides new tools for rational reverse genetics and targeted recombination. Cellectis develops Meganucleases that can induce unique site-directed double-strand breaks in a living cell, and can be used for biotechnological and therapeutical applications. The company is focusing on bringing "genome surgery" to clinic as a genuine new molecular medicine approach.

Celliance offers an expanding array of bioprocessing products and services including diagnostic products, contract research and manufacturing services (thru Celliance BioServices), and cell culture media supplements, including EX-CYTE®, the largest selling cell growth supplement, Probumin^TM, a proprietary line of bovine serum albumin and Incelligent^TM, the Company's recombinant human insulin. It is also the world's leading provider of monoclonal antibodies for the blood typing industry. Celliance is a Serologicals company based in Atlanta, GA.
For more information, please visit our website: www.celliancecorp.com.

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