CSF1R and graft versus host disease: This hypothesis proved valid in a mouse model of GVHD indicating that macrophages resisted in lymphoid tissues after lethal irradiation and elimination by anti-colony stimulating factor 1 receptor (anti-CSF-1R), which is expressed on all monocytes and tissue macrophages and plays a key role in their homeostasis (130), led to exacerbated GVHD (131).