MINNEAPOLIS — A child who received a cord blood transplant to try to cure him of both HIV and leukemia has died.

The transplant was performed at the University of Minnesota's Amplatz Children's Hospital in April.

A statement issued by the university on Friday says 12-year-old Eric Blue, of Alexandria, La., died July 5.

The university says the boy's response to the novel treatment initially was promising. But last month he developed a severe complication called graft-versus-host disease that happens when the donor cells attack various tissues in the recipient's body.

Cord blood transplants aren't unusual as a treatment for leukemia alone, but doctors were hoping that a rare mutation in the specific donor's cord blood that can guard against HIV infections would lead to a cure for both the boy's diseases.