Stem Cell Sciences plc
25 July 2005

25 July 2005

Stem Cell Sciences plc

US Patent and Trademark Office grants Stem Cell Selection Patent

Stem Cell Sciences Ltd, (SCS) which recently listed on the London Stock Exchange's Alternative Investment Market (AIM), announced today that the US Patent and Trademark Office ("USPTO") has granted important additional claims to the patented technology known as 'Stem Cell Selection'.

'Stem Cell Selection' refers to the methods and tools used to obtain pure populations of stem cells used in drug discovery and cell therapies.

The new claims (US Patent 6,878,542) cover methods of enriching for any type of mammalian stem cell, from any cell source, based on introduced genes such as fluorescent markers or cell surface proteins. This extension broadens the granted US claims to a similar scope to that already granted in other territories including the EU.

SCS expects the broadening of the patent claims to generate considerable new business through licensing of its technology to the US biopharmaceutical industry.

Dr Tim Allsopp, Chief Scientific Officer of Stem Cell Sciences explained "Having a sophisticated technology to derive highly purified populations of stem cells, for example, nerve, heart, liver or blood stem cells, is a fundamental requirement for almost all stem cell applications, including cell therapies".

Dr Peter Mountford, President and CEO of Stem Cell Sciences, said, "This is a very important technology for our field. SCS is committed to facilitating broad access to its key technologies and reagents in order to advance stem cell research and development. The valuable 'tool box' nature of this technology has already provided multi-million dollar revenues for the Company. Developing new research partnerships and licensing agreements in the USA for the 'Stem Cell Selection' technology is an important component of the Company's plans to establish US based operations in 2006."

The creation of Stem Cell Sciences USA will be the fourth leg of the Stem Cell Sciences global alliance, which includes science and business teams at Stem Cell Sciences UK (Edinburgh, UK), Stem Cell Sciences KK (Kobe, Japan) and Stem Cell Sciences Ltd (Melbourne, Australia)".

Further information at or contact:

Nicky Hawkins, Trimedia Communications
Telephone: 0131 272 2715

Notes to Editors:

Stem cells are undifferentiated (un-specialised) cells which can divide to make copies of themselves or differentiate (change) to become specialised cells of a specific tissue such as neural cells or bloom cells.

Stem Cell Sciences plc: Stem Cell Sciences Australia was founded in 1994 to commercialise the stem cell research of Professor Austin Smith and Dr Peter Mountford at the University of Edinburgh. In 2000 Stem Cell Sciences UK was established, followed by Stem Cell Sciences KK Japan in April 2002, with the objective of collaborative research with the RIKEN Centre for Developmental Biology (RIKEN CDB) in Kobe, Japan. In July 2003, with the incorporation of Stem Cell Sciences Holdings in Scotland, Edinburgh became the Group's headquarters. On July 18 2005 Stem Cell Sciences plc listed on the London Stock Exchange's Alternative Investment Market (AIM).