Stay Updated on Developing Stories

As Trump hails Regeneron treatment, his administration tries to block the science it used

(CNN) President Donald Trump has been celebrating the dose of experimental monoclonal antibodies he was given last Friday, saying he thinks it helped him vanquish his coronavirus infection in record time.

"It was incredible the impact it had," he said in a video he tweeted Thursday.

What he didn't say is that the treatment was developed using technology his administration has worked for four years to ban.

It has to do with abortion politics, and the science of using human tissue to test and to make medicines. Regeneron's therapy indirectly relied on tissue taken from an abortion.

Trump's base, of course, is strongly against abortion rights and his administration acted quickly to reverse many Obama era policies -- including policies that moved forward scientific research involving human fetal tissue.

Especially involved are human embryonic stem cells, made using days-old embryos, usually taken from fertility clinics. They're left over from when couples make extra fertilized eggs and then do not need them. In the past, this tissue was also sometimes taken from abortions.

People against abortion rights oppose both uses, as does the Trump administration. The US Department of Health and Human Services has stopped the National Institutes of Health from obtaining any more fetal tissue for research and has set up a board that has virtually stopped it from funding any academic groups that use it.

The federal government cannot stop private industry from using fetal tissue and Regeneron supports its use.

While Regeneron did not directly use human fetal cells to make the monoclonal antibody treatment given to Trump, it did use cells derived from an abortion in the Netherlands back in 1972 to make the targets for its antibodies -- the mimics of the coronavirus' spike protein.

Monoclonal antibodies home in on specific targets. To fight coronavirus, they are engineered precisely to attack the spike protein used by the virus to grapple onto cells. To make sure their antibodies were working right, Regeneron needed to use laboratory facsimiles of this spike protein, and for that, they used the fetal cells.

Scientists have used this batch of cells, called the HEK-293 cell line, for close to 50 years for all sorts of experiments. It's one reason these embryonic stem cells are so valuable. They have a kind of immortality and flexibility that other cells do not. It's why scientists fight so hard to keep access to this research, despite the efforts of anti-abortion activists.

"Research using such stem cells allows Regeneron to model complex diseases, test new drug candidates and can help unlock new scientific insights that ultimately could lead to the discovery of new treatments for people with serious diseases," the company said in a statement posted last April.

Fetal tissue was used to develop vaccines, including vaccines against rabies and rubella, or German measles. It's been used to develop drugs to treat the AIDS virus and cancer, and is used to study treatments for Parkinson's disease, spinal cord injuries and degenerative disease such as ALS.

To make its treatments, including its Covid-19 treatments, Regeneron uses another technology that frightens some people -- genetically engineered mice that have partly human immune systems and that produce human antibodies.

The point is to use the mice as efficient factories to grow antibodies that the human body will recognize and not reject.

Regeneron made its monoclonal antibodies by genetically engineering mice so they would produce human antibodies, and injecting them with the coronavirus spike protein. The mice produced thousands of antibodies in response. The company also used antibodies from people who had recovered from coronavirus infections and then chose two antibodies out of the mix that worked best to neutralize the coronavirus.

The company calls the mixture REGN-COV2 for now. It will get a brand name if it gets emergency use authorization from the US Food and Drug Administration. The company applied for that Wednesday.

Regeneron is still testing its dual antibody cocktail in volunteers -- both in people hospitalized with coronavirus and in people at high risk of infection, such as those who live with a patient.

Outbrain