B lymphocyte protein factories produced by hematopoietic stem cell gene editing.

Long-term in vivo production of therapeutic proteins and development of vaccines that elicit protective levels of broadly neutralizing antibodies (bNAbs) against major pathogens face challenges. In this study, we report on an alternative gene editing approach using small numbers of hematopoietic stem and progenitor cells (HSPCs) to direct long-term, high-level expression of antibodies or cargo proteins. In mice, edited B lymphocytes derived from transplanted HSPCs were activated by cognate antigen, underwent clonal expansion, and developed into specific antibody-synthesizing or cargo protein-synthesizing plasma cells. These cells produced long-lasting, therapeutic levels of serum antibody against HIV-1, malaria, or an anti-influenza virus bNAb that mediated universal protection from heterologous lethal challenge. Our data provide a paradigm for cell therapy approaches to prevent or treat disease using self-amplifying B cell protein factories.