Fig. 3

CAFs protect leukemia cells from chemotherapy a Morphological observations of the MSCs and the CAFs. Both images are at a magnification of 100×. b Flow cytometry analysis showed expression levels of a-SMA and FAP in the MSCs and the CAFs. c Western blotting for collagen I, collagen III, FSP1, α-SMA and FAP in the MSC and the CAF cells. d Bar plots illustrating the viability of THP-1 and K562 cells which were cultured in medium alone or direct co-cultured with MSCs or CAFs under treatment of Ara-C (10uM) for 48 h. e Cell cycle of the residual THP-1 cells which were treated with Ara-C (10uM) for 48 h when co-cultured with CAFs or not were analysized by propidium iodide staining and flow cytometry. f Apoptosis of THP-1 and K562 cells which were co-cultured with CAFs (right) or not (left) were evaluated by AnnexinV/PI staining and flow-cytometry. Data were presented for one of the triplicate experiments. g Bar plots showed the viability of THP-1 and K562 which were cultured in medium alone or co-cultured with CAFs in a transwell system under treatment of Ara-C (10uM) for 48 h. h The THP-1 and K562 cells were cultured in medium with different ratios of CAF conditioned medium (CAF-CM) under treatment with Ara-C (10uM) for 48h. i: The viable cells of THP-1 (white bar) and K562 (gray bar) which were co-cultured with a CAF layer under Ara-C treatment for 48h after pretreated with SB431542 or not were evaluated by trypan blue exclusion assay Data were presented as mean ± SD of triplicate experiments.* p < 0.05,** p < 0.01, ***p < 0.001