PTPRC and neoplasm: We employed CD45+ to identify tumor-associated bone marrow cells 14 days after co-injection with 4T1-FLUC cells and cMSCs or untreated MSCs, and found that there was a great expansion of the populations of CD45+ cells in tumors, an effect that was dramatically greater with the cMSCs than untreated MSCs (Figure 2E, 2F).