Osiris Therapeutics, Inc. (OSIR) Chief Executive Officer to Ring the NASDAQ Stock Market Closing Bell


ADVISORY, Aug. 1, 2007 (PRIME NEWSWIRE) --



 What:
 C. Randal Mills, Ph.D., President and Chief Executive Officer of
 Osiris Therapeutics, Inc. (Nasdaq:OSIR) will preside over the
 closing bell.

 Where:
 NASDAQ MarketSite - 4 Times Square - 43rd & Broadway - Broadcast Studio

 When:
 Friday, August 3, 2007 at 4 p.m. ET

 Contacts:
 Erica Elchin
 443-545-1834
 eelchin@osiris.com

 NASDAQ MarketSite:
 Jolene Libretto; 646.441.5220; 347.219.9539
 Jolene.Libretto@NASDAQ.com

Feed Information:

The closing bell is available from 3:50 p.m. to 4:05 p.m. on uplink IA-6 C-band/transponder 17. The downlink frequency is 4040 Vertical; Audio 6.2-6.8 The feed can also be found on Waterfront fiber 1623. If you have any questions, please contact Jolene Libretto at (646) 441-5220.

Radio Feed:

An audio transmission of the closing bell is also available from 3:50 p.m. to 4:05 p.m. on uplink IA6 C band / transponder 24, downlink frequency 4180 horizontal. The feed can be found on Waterfront fiber 1623 as well.

Webcast:

A live Webcast of the NASDAQ Closing Bell will be available at: http://www.nasdaq.com/reference/marketsite_about.stm

Photos:

To obtain a hi-resolution photograph of the Market Close, please go to http://www.nasdaq.com/reference/marketsite_events.stm and click on the market close of your choice.

About Osiris Therapeutics, Inc. (OSIR):

Osiris Therapeutics, Inc. is a leading stem cell therapeutic company focused on developing and marketing products to treat medical conditions in the inflammatory, orthopedic and cardiovascular areas. Osiris currently markets and sells OSTEOCEL(r) for regenerating bone in orthopedic indications. PROCHYMAL(tm) is in Phase III clinical trials and is the only stem cell therapeutic currently designated by FDA as both an Orphan Drug and Fast Track product. The company's pipeline of internally developed biologic drug candidates under evaluation also includes CHONDROGEN(tm) for regenerating cartilage in the knee, and PROVACEL(tm), for repairing heart tissue following a heart attack. Osiris is a fully integrated company, having developed stem cell capabilities in research and development, manufacturing, marketing and distribution. Osiris has developed an extensive intellectual property portfolio to protect the company's technology in the United States and a number of foreign countries including 47 U.S. and 167 foreign patents owned or licensed. More information can be found on the company's website, www.Osiris.com. (OSIR-G).