Fig. 3.
Inhibition of differentiation of ES cells. Supernatants of COS cells transfected with mock, mOSM, and hOSM cDNAs were concentrated 20-fold by ultrafiltration. CCE (ES cell line) cells (3.5 × 102) were incubated in 24-well multiwell plates with a serial dilution of the supernatants as indicated for 5 days. Cells were stained with Giemsa solution after methanol fixation. Dispersed and compact stain dots in each well represent differentiated and undifferentiated ES cell colonies, respectively.