Abstract
Microenvironments provide cues to stem cells and induce signals to direct their fate. With a view toward further understanding the correlation between surface chemistry and cell functions of stem cells, adipose-derived stromal cells (ADSCs) and self-assembled monolayers terminated with four different functional groups (–CH3, –NH2, –COOH and –OH) were used to assess cell adhesion, migration and differentiation potential in short-term incubation. Quantitative time-lapse microscopic analysis revealed that migration speed and patterns were strongly regulated by surface chemistry. ADSCs showed a mesenchymal migration pattern on the –COOH-modified surface. In contrast, cells on the –CH3-modified surface displayed an amoeboid-like migration pattern. Cell-migration speeds on the chemically-modified surfaces followed the sequence (by tail-groups): –CH3>–COOH>–OH>–NH2. After 1 day of incubation, ADSCs showed a round compact shape and adipogenic differentiation potential on the –CH3-modified surface. The round compact shape and extremely different migration pattern of ADSCs on –CH3 surfaces were attributed to the lower amount of exposed cell-binding domains of adsorbed proteins. ADSCs exhibited spindle-like shape and higher Collagen II expression on the –COOH-modified surface and well-spread morphology and higher Runx2 expression were observed on the –NH2- and –OH-modified surfaces. Surface chemistry presented a strong influence on cell functions of ADSCs, including cell adhesion, migration and mRNA expression in short-term incubation.
Acknowledgements
This work was supported by generous grant from the National Science Council of Taiwan (NSC-99-2221-E-006-013-MY3) and Top 100 University Advancement and Center for Micro/Nano Science and Technology, National Cheng Kung University, Taiwan (D99-2740).