TMC PULSE

9 t m c p u l s e | j u ly 2 02 0 Scientists are investigating an array of exist- ing drugs as potential treatments—including remdesivir and tocilizumab—but another promis- ing avenue is convalescent plasma therapy. Plasma, the translucent, straw-colored component of blood, is often called "the gift of life." In addition to glucose, clotting factors and electrolytes, plasma is rich in antibodies that are produced by the immune system to seek and destroy foreign substances in the body, such as bacteria and viruses. Patients who have fully recovered from COVID-19 carry antibodies in their plasma that their immune system produced to attack the virus. Transfusing that plasma into patients still suffering from the disease may arm them with the COVID-19-fighting antibodies they need to recover. On March 28, Houston Methodist received approval from the U.S. Food and Drug Administration to become the first academic medical center in the nation to transfuse donated plasma from a recovered COVID-19 patient into two critically ill patients. Since then, the hospital has recruited 100 plasma donors. "What makes these donors special is that they contact with anybody." Knight entered the main house for food, water or clothes. He washed his hands and face each time he entered, using a Clorox wipe to open doors and clean any surfaces he touched. While his wife, 10-year-old daughter and 7-year-old son gathered at the dining table for dinner, Knight ate at the kitchen counter 12 feet away from his family. Even though he was close by, he felt far away. "It was really awful. You'd be looking at the kids. They'd be looking at you and they want to come over and hug you, but they can't," he said. "It just kills you. … It was a matter of being alone." Finally, on Monday, April 13, Knight's third test came back negative. "When I was finally out, my son and my daughter grabbed onto me for five minutes," he said. "Then, 15 minutes later, they're trying to beat each other up—but for those five minutes, it was a very nice moment." Plasma therapy With no approved vaccine for COVID-19, the global scientific community has been racing for a cure. have a documented history of COVID-19 infec- tions, so we anticipate, based on the literature that's been done, that we're going to have a brisk antibody response in them," said James Musser M.D., Ph.D., chair of the department of pathology and genomic medicine at Houston Methodist Research Institute. More than a century old, convalescent serum therapy was used to treat patients during the Spanish flu pandemic of 1918, the diphtheria epidemic in the United States in the 1920s, a flesh-eating bacteria outbreak in the 1930s and the Ebola outbreak in 2014. Knight, who was familiar with Houston Methodist's groundbreaking work in convalescent plasma therapy, signed up to become a donor immediately after he received a clean bill of health. His wife, who relies on plasma donations, understands firsthand the importance of her hus- band's contribution. She had been encouraging him to donate blood and plasma for years, but it took a pandemic for him to overcome his aversion to needles. "Even though he had the virus, at least something good was coming out of it," Lyndsey Knight said. Daniel Knight donated a quart of plasma for the first time on April 14 and again three days later. "Those of us who [have recovered], we have a unique opportunity to help," he said. "You have a chance to potentially save a life … [by] letting doctors and scientists try to find an effective treatment for people who are way sicker than I was. If we can do that together, then that's how we're going to get back to as close to normal as we were before." Since April, Daniel Knight has donated his plasma more than 10 times and plans to continue donating for as long as he has the antibodies in his system and as long as Houston Methodist will take his donations. "You can turn toward darkness and despair and feel like it's never going to be the same, or you can look through a lens of hope and say, 'This stinks. It sucks. It's awful, but we're going to overcome it together,'" Knight said. "Me doing the plasma donation is just a small part of that, but I feel as though I have to do what I can." Knight looks out onto the back yard of his Houston home.

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