MSC surface receptor expression decreased over time in the presence of pullulan. Assessment of CD44, CD90, CD73 and CD105 receptor expression was made by cytometric flow analysis, after one, three and seven days exposure to increasing concentrations of pullulan. (A) There was no significant difference in receptor expression between MSCs incubated in 2% and 5% pullulan as compared to 0% controls after one day. (B) There was a decrease in overall receptor surface expression for all groups after three days of culture. A decrease was observed in expression of CD90, CD73 and CD105 for MSCs cultured in 5% pullulan after three days compared to 0% and 2% treated cultures; however, it was not statistically significant. (C) A further decrease in CD44, CD90, CD105 and a significant decrease in CD73 receptor expression was noted after seven days of MSC culture in 5% pullulan. Data are presented as the mean ± SD of n = 3 biological replicates generated using triplicate measurements, * = P ≤0.05. MSC, mesencgymal stem cells; SD, standard deviation.