In 2017, Deng and his collaborator, Chen Hu of the 307 Hospital, used CRISPR gene editing to transplant human hematopoietic stem cells with the edited CCR5 gene to mice, and conferred HIV resistance to the animals.[7] They subsequently used the technique to treat an AIDS patient who suffered from acute lymphoblastic leukemia (ALL). It was the first time CRISPR was used on a human HIV patient.