CIITA and neoplasm: However, there were not still conclusive for a direct priming of virgin tumor specific CD4+ Th cells, as the possibility existed that MHC-II-tumor antigen complexes shed by CIITA-tumor cells or derived by apoptotic/necrotic tumor cells and captured by DC, could be used by DC to complement their otherwise insufficient APC function in lymph nodes, by a mechanism of cross-dressing [45,53] or by the recently described intracellular vesicle exchange between distinct subpopulation of DCs [54].