To investigate the effects of Tat on macrophage IKKβ activation and atherosclerosis development in vivo, myeloid-specific IKKβ-deficient LDLR-deficient (IKKβΔMyeLDLR−/−) mice and their control littermates (IKKβF/FLDLR−/−) were exposed to recombinant HIV protein Tat. The gene discussed is LDLR; the disease is atherosclerosis.