Stem cell researchers say immense progress has been made in the decade since human cells were first isolated and grown by U.S. scientists.

Over the last decade, researchers have learned how to turn embryonic stem cells into heart, brain and pancreatic cells, the Milwaukee Journal-Sentinel said Thursday. The newspaper said stem cell research has reshaped regenerative science. The International Society of Stem Cell, formed with 150 members in 2002, now has more than 2,600 members from 45 countries.

James Thomson, author of the 1998 University of Wisconsin-Madison report published in the journal Science, said questions surrounding possible therapeutic applications remain to be answered. He said he continues to seek the answer to why one cell can make anything in the whole body and another can't.