THY1 and neoplasm: Figure 2A shows the gating strategy to isolate MSCs from cryopreserved BM. First, viable CD34 and CD45 negative cells were selected. From this CD34− CD45− cell population, we used CD90 and CD105 to further isolate four populations: (1) The CD90+CD105+ MSC population that we expect to be MSCs, hence named ‘Expected-MSC (ExpMSC)’, (2) CD90+CD105− population, containing CD90-expressing tumor cells [31,32], hence named ‘Expected-NB (ExpNB)’, (3) CD90−CD105− population, and (4) CD90−CD105+ population.