Rockefeller University scientists presented a CRISPR-based strategy that reprograms hematopoietic stem and progenitor cells (HSPCs) to produce engineered B-lymphocyte protein “factories.” In mice, the edited B cells expressed antibody cargo and expanded after vaccination exposure, driving long-lasting, boostable antibody output. The Science study (“B lymphocyte protein factories produced by hematopoietic stem cell gene editing”) reports that as few as ~7,000 edited HSPCs were sufficient to generate high-titer, durable protective or therapeutic antibody responses. The platform also broadened beyond antibodies by demonstrating secretion of non-antibody proteins and enabling multi-antibody mixes to reduce viral escape risk. The work underscores a shift from short-lived, mature-cell engineering toward upstream, genome-imprinted immune programming—an approach that could be adapted for rapidly evolving pathogens and certain genetic diseases requiring protein replacement.