Blood may be red, but the nurses called it “liquid gold.”

Two bags filled with a yellowish liquid were the end result of U.S. Rep. Mike Kelly's trip to donate his blood plasma.

But the congressman's plasma, which contains COVID-19 antibodies as a result of his recovery from the virus, could be given to four patients infected with the coronavirus as part of a nationwide clinical trial testing whether COVID-19 convalescent plasma can treat those who have the virus.

“If somebody else can benefit because of a small donation you make with your blood, what an incredible thing to do,” said Kelly, R-16th.

The two-hour trip to a Vitalant location in Greentree, Allegheny County, on Monday came from Kelly hearing about the convalescent plasma program and knowing, he said, that participating in it was the right thing to do.

“(It's) very easy to do, very safe to do, and I think more than anything else, you get a feeling that, maybe I helped somebody I'll never meet, I'll never know, but maybe they'll benefit from the hour and a half I spent donating my plasma,” Kelly said.

The blood plasma of people who have recovered from COVID-19 contains antibodies for the disease, potentially helping current patients' immune systems recognize and target SARS-CoV-2, the coronavirus at the helm of the pandemic.

The plasma of recovered patients — called convalescent plasma — has been examined as a treatment for other respiratory illnesses, including the original SARS in 2003; the H1N1 flu in 2009-10; and MERS in 2012, according to the U.S. Food and Drug Administration. While it hasn't been proven safe and effective in COVID-19 patients, the FDA calls it “promising” and allows the study of convalescent plasma in such patients.

“The concept for using convalescent plasma falls under the idea of passive immunity,” said Dr. John McDyer, director of the UPMC Lung Transplantation Translational Research Program. “Individuals who don't have immunity get immunity from a source, like blood, that is given to them.”

Alongside drug therapies, like remdesivir or steroids, UPMC is studying convalescent plasma as a treatment for COVID-19, along with other research hospitals throughout the United States.

This is an excerpt of a story that will appear in Wednesday's Butler Eagle. To read the full article and learn more about convalescent plasma's potential in the fight against COVID-19, pick up tomorrow's paper or subscribe online.