Baboon bone marrow implanted in an AIDS patient to boost his failing immune system has apparently failed to work, doctors said Wednesday.
But the AIDS patient, 38-year-old Jeff Getty, is doing “surprisingly well,” perhaps due to chemotherapy, said Dr. Steven Deeks, who performed the transplant at San Francisco General Hospital on Dec. 14.
The bone marrow was transplanted into Getty to produce a parallel immune system because baboons do not get AIDS.
Previous experiments with baboon bone marrow transplants had failed because the bodies of the human patients rejected the foreign cells.
The treatment Getty received was designed by Dr. Suzanne Ildstadt at University of Pittsburg Medical Center.
She added special facilitator cells to baboon bone marrow stem cells in hopes it would help the cells engraft into Getty’s system and begin producing disease-fighting baboon immune system cells.
But after two months, doctors have failed to find any clear signs of baboon cells, Deeks said.
“At this point in time the results are inconclusive, but suggest that if there are any cells present, there aren’t very many of them,” Deeks said.
Despite the apparent failure, Getty said he is feeling well.
“My immune system is doing wonderfully,” he said.
Getty said doctors believe the radiation and chemotherapy prior to the transplant may be responsible for a sharp decrease in the virus’ presence in his body.
Getty and Deeks emphasized that the procedure was successful in the only area approved by the FDA showing that the baboon bone marrow transplant into a human being was safe.
Critics had objected to the baboon-to-human transplant because of fears that a baboon disease could be unleashed on the population through the transplant process. Deeks said the transplant proved that so far, the fears are unfounded.
Deeks said he intends to repeat the trans plant with knowledge gained from Getty’s experience. The engraftment may have failed because Getty’s immune system was not sufficiently suppressed before the transplant, he said. “We erred on the conservative side, with very low doses of radiation and very low doses of chemotherapy,” he said. “The chance of getting stem cell engraftment was very low.”