Carbon nanotube-based substrates for modulation of human pluripotent stem cell fate
We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment.
© 2014 Elsevier Ltd. Received 13 January 2014; Accepted 7 March 2014; Available online 29 March 2014. We wish to thank Dr. I. Slukvin and Dr. K. Hu (University of Wisconsin-Madison) for hiPSC lines provided. We also would like to acknowledge Dr. Julia Greer's help with nanoindentation measurements of carbon nanotube arrays. We also would like to acknowledge W. M. Keck Foundation Open Laboratory at USC for the help with AFM measurements. We gratefully acknowledge support from the National Institute of Health (Grant NIH P20 GM103641) and National Science Foundation (Grant EPS-0903795).
Accepted Version - nihms-790363.pdf