Transduced B cells: B is for 'beneficial'!

B cells have been used as tolerogenic APCs for nearly two decades. However, the ability to transduce B cells for use in gene therapy has been hampered by the low efficiency of transduction of resting B cells. This has been partially overcome by mitogenic activation of these cells, a factor that is not without risks as activated B cells may become pathogenic. In this issue of the European Journal of Immunology, this challenge is met by achieving high-efficiency transduction of resting murine B cells with a lentiviral vector. Furthermore, the application of this protocol to generate MOG-expressing B cells and successfully prevent EAE, as described in this issue, is an important step forward in B-cell therapy.