MADISON, Wis.— As a 6th grader faces his third battle with an aggressive and rare leukemia, his doctor is putting out an urgent plea to be his hero and consider donating your plasma.

Holden Zarda is a Spiderman-loving-little boy who is undergoing groundbreaking therapy. Just weeks ago, at the American Family Children's Hospital, genetically engineered 'Killer-T' cells— made from a disabled virus— attacked Holden’s cancer during a potentially life-saving infusion. 

"The technology is that it's using his own his body's cells, and just helping them to recognize and kill the Leukemia, so it's a real form of personalized medicine," UW Health pediatric oncologist Dr. Christian Capitini said.

But in the process, the 'Killer-T' cells also destroyed Holden's healthy B-cell antibodies. 

"This is something that has become more of a popular topic with COVID because we know people who've had COVID can have antibodies to COVID after they recover from the infection, and so we've been asking them to come donate," Dr. Capitini said. "And similarly, by donating plasma and specifically immunoglobulin, you can help protect patients like Holden from having any unfortunate complications after going through such aggressive therapy." 

Holden will receive a bone marrow biopsy next week to see how the treatment is progressing. 

If you’d like to help the Pickerel, Wisconsin boy while he receives treatment and evaluation in Madison, click here.