A transgenic construct containing sequence encoding cre recombinase under the control of the mouse integrin alpha X (Cd11c) promoter, and a bovine growth hormone poly A signal sequence, was introduced into B6CBAF1/J donor eggs. BAC clone RP24-361C4 (BACPAC Resources) containing the Itgax (Cd11c) gene but lacking the 5' end of the adjacent Itgam gene, was modified by ET recombination to generated the transgene construct. Founder line 1-1 was consequently established. Cre recombinase expression is detected in CD8-, CD8+ dendritic cells, tissue derived dendritic cells from lymph nodes, lung and epidermis and plasmacytoid dendritic cells. Background recombination is detected in lymphocytes (<10%) and myeloid cells (<1%).