Source: Asterias Biotherapeutics FREMONT, Calif., Aug. 23, 2017 (GLOBE NEWSWIRE) — Asterias Biotherapeutics, Inc. (NYSE MKT:AST), a biotechnology company pioneering the field of regenerative medicine, today announced that Washington University School of Medicine in St. Louis, MO, has been added as a clinical site in the company’s ongoing SCiStar Phase 1/2a clinical trial of AST-OPC1…