Gene editing strategies that do not rely on viral vectors are being explored for their potential to support durable biologics production. While clinical trials have shown that adeno-associated virus encoding broadly neutralizing antibodies can protect against HIV, these interventions often yield limited, short-lived responses. The development of non-viral gene editing approaches in hematopoietic stem and progenitor cells holds promise for long-term antibody production. In this study, we evaluated CRISPR/Cas9 and CRISPR/Cas12a for gene knock-in at the immunoglobulin heavy chain locus in non-human primate (NHP) hematopoietic stem and progenitor cells (HSPCs). Delivering the nuclease as a protein alongside a custom DNA template, we optimized editing with Cas12a and demonstrated higher knock-in efficiency and fewer non-specific edits than Cas9. Transplantation of edited NHP HSPCs into MISTRG mice led to engraftment, B cell differentiation, and transgene expression of a reporter transgene or anti-HIV antibody after gp120 antigen immunization with detectable titers in circulation. These findings demonstrate the feasibility of using non-viral knock-in in HSPCs as a potential strategy for sustained biologics production in the treatment of chronic diseases. Future work will assess the efficacy of this approach in a NHP model of HIV infection.
Castelli et al. (Sun,) studied this question.