Targeting the gastrointestinal tract with viral vectors: state of the art and possible applications in research and therapy.

While there is a large body of preclinical data on the use of viral vectors in gene transfer, relatively little is known about viral gene transfer in the gastrointestinal tract. Viral vector technology is especially underused in the field of neurogastroenterology when compared to brain research. This review provides an overview of the studies employing viral vectors-in particular retroviruses, adenoviruses and adeno-associated viruses-to transduce different cell types in the intestine. Early work mainly focused on mucosal transduction, but had limited success due to the harsh luminal conditions in the gastrointestinal tract and the high turnover rate of enterocytes. More recently, several studies have successfully employed viral gene transfer to target the enteric nervous system and its progenitors. Although several hurdles still need to be overcome, in particular on how to augment transduction efficiency and specific cell targeting, viral vector technology holds strong potential not only as a valid research tool in fundamental gastroenterological research but also as a therapeutic agent in translational (bio)medical research.