Figure 3. Colony forming unit frequency is enhanced by serum of aplastic patients.
CD34+ HPC were cultured either without stroma (A) or in co-culture with MSC (B) in culture medium supplemented with serum taken before chemotherapy or day 8 after HSCT. After seven days of in vitro expansion, cells were re-seeded in methylcellulose medium and after two weeks numbers of granulocyte (CFU-G), macrophage (CFU-M) and erythrocyte colonies (CFU-E) were counted. Overall, colony formation was enhanced upon expansion with d8 serum. CFU-frequency was greatly increased by co-culture with MSC, and this was further stimulated by serum from d8. Furthermore, cobblestone area forming cell (CAFC) frequency was determined after 4 weeks of co-culture with MSC (C). The CAFC frequency was greatly enhanced by addition of d8 serum (D) (n = 4; * = p<0.05; ** = p<0.01; error bars represent SEM; size bar = 100 µm).