Some studies have used vectors encoding B7–1 (CD80), ICAM-1, and LFA-3 to efficiently overexpress these costimulatory molecules in dendritic cells (DCs) and leukemia cells, after which an increased antigen-presenting potency of these cells was observed compared to their uninfected counterparts, as demonstrated by enhanced T cell responses [20, 21]. This evidence concerns the gene CD80 and leukemia.