It is unclear whether the ruling would force current NIH grants for human embryonic stem cell research to come to a halt, or merely prevent the agency from doling out new money for the work. Lamberth said his injunction "would simply preserve the status quo and would not interfere with [scientists'] ability to obtain private funding for their research."
But the NIH has invested $395 million in human embryonic stem cell research since 2005 and is projected to spend another $127 million this year. Under Obama, the NIH has deemed at least 75 human embryonic stem cell lines eligible for use in federally funded projects, including five that were approved for use under Bush.
UCLA law professor Russell Korobkin, an expert on stem cell legal issues, said the ruling was "a terrible decision."
By considering all research part of an unbreakable continuum, the decision implies that the Dickey-Wicker Amendment has no limits, which is an unconvincing interpretation, Korobkin said. "It suggests that by conducting research on an acorn a scientist would also be conducting research on an oak tree, because acorns come from oak trees," he said.
The NIH has maintained since 1999 that the Dickey-Wicker Amendment precludes only the derivation of human embryonic stem cells, not their use as an experimental tool. The fact that Congress has not fine-tuned the law since then to explicitly ban funding for the research is evidence that the NIH is correct, Korobkin said.
The case originally included the Christian Medical Assn., an embryo adoption agency called Nightlight Christian Adoptions and other plaintiffs, but courts removed them from the case.
An appeals court allowed the two researchers to proceed on the grounds that the expansion of NIH funding for human embryonic stem cells made it more difficult for them to win grants for their work on other types of stem cells derived from adult tissues.
Kaplan reported from Los Angeles, and Levey reported from Washington.
Times staff writer Thomas H. Maugh II in Los Angeles contributed to this report. Kaplan reported from Los Angeles and Levey reported from Washington.