Texan man makes stem cell history
Special to The Dallas Examiner | 6/27/2016, noon
Special to The Dallas Examiner
Chuck Dandridge, a Mansfield resident, became the first adult in the U.S. to receive a newly modified stem cell transplant that uses genetically engineered blood cells from a family member, according to researchers at UT Southwestern Medical Center’s Harold C. Simmons Comprehensive Cancer Center where the procedure was performed.
The new genetically engineered blood cells were transplanted from his son, Jon Dandridge, and as a result of the procedure, Chuck’s leukemia is in remission.
“Giving my dad the same gift of life that he gave me when he brought me in this world was the most amazing feeling a son could have,” Jon Dandridge said. “I always wondered how I could give something back to my parents who have given me so much.”
In three two-hour infusions at William P. Clements Jr. University Hospital last July, Chuck Dandridge, 65, received the life-giving transplant from his 31-year-old son.
“My skin is my own DNA, but inside I’m all Jon,” he stated. “I have my son Jon’s DNA in my blood stream, bone marrow and immune system.”
Chuck’s transformational journey began in 2013 when he visited his doctor for a routine check of his cholesterol levels and laboratory tests revealed low blood counts. He was diagnosed with myelodysplastic syndrome, also called pre-leukemia or MDS. By 2014, his disease had progressed to acute myeloid leukemia, which affects more than 20,000 Americans annually, according to the National Cancer Institute.
He was referred to UT Southwestern’s cancer center where his disease was tested for genetic mutations.
“We wanted to know whether he had specific mutations in his cancer cells. We found a mutation called IDH 2, which causes the body to produce an abnormal protein that promotes excessive cell growth. If you can target that mutation and stop the abnormal protein from being produced, then cells start behaving normally,” said Dr. Madhuri Vusirikala, professor of Internal Medicine and the primary investigator of many UT Southwestern clinical trials related to bone marrow transplantation.
Chuck enrolled in a UT Southwestern clinical trial studying a therapy called AG-221, developed by Agios Pharmaceuticals and the Celgene Corporation. He took four pills each morning for the next eight months.
“We saw marked improvement. He did not go into complete remission, but had an excellent response,” said Vusirikala, who is also the director of UT Southwestern’s National Marrow Donor Program, part of the stem cell transplant program. That success made him eligible for a potentially curative stem cell transplant.
But finding a donor then proved challenging, because minorities are under-represented in the registry, with about 70 percent of donors in the National Marrow Donor Registry being Caucasian – making it less likely for African Americans like Chuck to be matched.
“The best chance of finding a full match is usually a full sibling; however, Chuck has no full siblings,” Vusirikala said.
A search for an unrelated donor proved unsuccessful.
“We knew his daughter and his son would be at least a half match. Using a same-sex donor is preferred because it reduces the risk of complications, so his son Jon emerged as the best choice,” the physician explained. “But the risk of graft-versus-host-disease – known as GvHD – following a transplant using a half-match is very high, so we needed a better way to deal with the GvHD risk.”