Combining Cell-Intrinsic and -Extrinsic Resistance to HIV-1 By Engineering Hematopoietic Stem Cells for CCR5 Knockout and B Cell Secretion of Therapeutic Antibodies.

Autologous transplantation of null hematopoietic stem and progenitor cells (HSPCs) is the only known cure for HIV-1 infection. However, this treatment is limited because of the rarity of -null matched donors, the morbidities associated with allogeneic transplantation, and the prevalence of HIV-1 strains resistant to CCR5 knockout (KO) alone. Here, we propose a one-time therapy through autologous transplantation of HSPCs genetically engineered to produce both CCR5 KO cells and long-term secretion of potent HIV-1 inhibiting antibodies from B cell progeny. CRISPR-Cas9-engineered HSPCs maintain engraftment capacity and multi-lineage potential and can be engineered to express multiple antibodies simultaneously. Human B cells engineered to express each antibody secrete neutralizing concentrations capable of inhibiting HIV-1 pseudovirus infection . This work lays the groundwork for a potential one-time functional cure for HIV-1 through combining the long-term delivery of therapeutic antibodies against HIV-1 and the known efficacy of KO HSPC transplantation.