Progressive and controlled development of mouse dendritic cells from Flt3+CD11b+ progenitors in vitro.

Dendritic cells (DC) represent key regulators of the immune system, yet their development from hemopoietic precursors is poorly defined. In this study, we describe an in vitro system for amplification of a Flt3(+)CD11b(+) progenitor from mouse bone marrow with specific cytokines. Such progenitor cells develop into both CD11b(+) and CD11b(-) DC, and CD8alpha(+) and CD8alpha(-) DC in vivo.

Transcriptional profiling identifies Id2 function in dendritic cell development.

Dendritic cells (DCs) are potent antigen-presenting cells with a pivotal role in antigen-specific immune responses. Here, we found that the helix-loop-helix transcription factor Id2 is up-regulated during DC development in vitro and crucial for the development of distinct DC subsets in vivo. Id2-/- mice lack Langerhans cells (LCs), the cutaneous contingent of DCs, and the splenic CD8alpha+ DC subset is markedly reduced.