In support of AML blasts possessing the ability to downregulate M1-like Mφs, Keech et al. (2017) showed that following the establishment of moderate to high levels of leukaemia burden in MLL-AF9 AML mice, non-malignant/AML BM Mφs displayed a reduction in M1 Mφ markers, including MHC class II and CD80. The gene discussed is CD80; the disease is acute myeloid leukemia.