Figure 1

Effect of heat-inactivation of serum on proliferation and calcification of human synovial and bone marrow MSCs. (A) Synovial or bone marrow MSCs were plated at 50 cells/cm² and cultured in the presence of autologous human serum or FBS for 14 days. Two kinds of serum, one with or one without heat-inactivation, were used. Fold increases from each donor are shown respectively (n = 3). * = P < 0.01; fold increases in the same donor with the same serum with and without heat-inactivation. (B) Alizarin Red-positive colony forming efficiency of synovial MSCs cultured in the calcification medium containing the serum with and without heat-inactivation(%). Synovial MSCs precultured with autologous human serum or FBS at passage 0 were plated at 100 cells in 150-cm² dishes. These cells were cultured in the medium containing the same serum used at passage 0 for 14 days to form cell colonies. Then, the medium was switched into calcification medium containing the same serum used at passage 0 with or without heat-inactivation and cultured for an additional 21 days. The dishes were stained with Alizarin Red for calcification. The ratio of Alizarin Red positive colony number to the total colony number was calculated (n = 3). Average value with standard deviation from a donor is shown.