Origin and differentiation of dendritic cells

Despite extensive, recent research on the development of dendritic cells (D Cs), their origin is a controversial issue in immunology, with important im plications regarding their use in cancer immunotherapy. Although, under def ined experimental conditions, DCs can be generated from myeloid or lymphoid precursors, the differentiation pathways that generate DCs in vivo remain unknown largely. Indeed, experimental results suggest that the in vivo diff erentiation of a particular DC subpopulation could be unrelated to its poss ible experimental generation. Nevertheless, the analysis of DC differentiat ion by in vivo and in vitro experimental systems could provide important in sights into the control of the physiological development of DCs and constit utes the basis of a model of common DC differentiation that we propose.