The U.S. government approved the first 13 batches of human embryonic stem cells on Wednesday, enabling researchers using them to get millions of dollars in federal funding as promised by President Barack Obama in March.

The batches, known as lines, were made by two researchers at Harvard University and Rockefeller University using private funds, said Dr. Francis Collins, director of the National Institutes of Health.

Today we are announcing the approval of the first 13 stem cell lines, Collins told reporters in a telephone briefing.

In March, Obama lifted restrictions on human embryonic stem cell research imposed by his predecessor, George W. Bush.

He could not lift a restriction set by Congress, called the Dickey-Wicker amendment, that forbids the use of federal money to make the stem cells, which require destruction of a human embryo. But the decision made it possible for researchers to use federal funds to work with cells that others have made.

The NIH set up a panel to decide which stem cell lines met strict ethical restrictions. The cells, for instance, have to have been made using an embryo donated from leftovers at fertility clinics, and parents must have signed detailed consent forms.

Stem cells are the body's ultimate master cells. They make up days-old embryos and have the power to give rise to all the cells and tissues in the body.

Scientists hope to use them to transform medicine by growing new tissue and repairing damage. Opponents say it is wrong to destroy human embryos for any reason.

ETHICALLY ACCEPTABLE

But Collins said the NIH-approved lines represent an acceptable compromise. I think the broad consensus among most of the public ... is that stem cell research of this ethically acceptable kind should go forward, he said.

These were derived from embryos derived under ethically sound consent processes.

The first 13 lines were open and shut cases, he said. Another 96 lines are under consideration and more approvals can be expected in the coming days, Collins said.

I think people are champing at the bit, he said. This is the first down payment in what is going to be a much longer list of such lines.

Eleven of the lines were made by Dr. George Daley of the Harvard Stem Cell Institute in Massachusetts. He said his lab started making the stem cells in 2006 using private donations and is looking forward to getting federal money.

It is a huge boost. It is a stimulus to my research, said Daley, who said he has hired three technicians in the past two weeks.

I can point to people and say 'Thank God for Obama -- you're here', Daley said in a telephone interview.

We have been very fortunate at Harvard to have been the beneficiaries of philanthropy but it has dried up in past years, in part because of the economy and in part because of the perception that the government was about to step in and clear everything up.

The NIH says it has funded 30 proposals totaling more than $20 million that would use human embryonic stem cells. Now the researchers can get the cells and get going, it said.

This group of grants includes research using human embryonic stem cells for the therapeutic regeneration of diseased or damaged heart muscle cells, developing systems for the production of neural stem cells among others, it said.

Collins said these cells are still needed for research even though scientists have found ways to turn ordinary cells into what resemble embryonic stem cells.

I think one could make a very strong case that we need both, he said.

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