Fig. 2: This is of osteoclasts stained for Tartrate Resistant Acid Phosphatase (TRAP). The top panel cells are osteoclasts differentiated from precursors that do not express TIEG (knockout) and the bottom panel cells are osteoclasts that differentiated from an equal number of normal precursors. Both mononuclear and multinucleated cells (arrows) are TRAP positive, but there are many more osteoclasts in cultures from TIEG knockout precursors. These data show that precursors lacking TIEG protein have an enhanced capacity to differentiate compared to precursors expressing TIEG protein.