The Impact of sub-µm Surface Topography on Pluripotent Stem Cells

• Applicants: Professor Dr.-Ing. Arnold Gillner; Professor Dr. Wolfgang Wagner
• Subject Area: Cell Biology ; Biomaterials ; Synthesis and Properties of Functional Materials
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 402197212

• Final Report Year: 2023

Final Report Abstract

In this project, we analyzed the impact of surface structures on growth of induced pluripotent stem cells (iPSC). Multi-beam interference technology was used to generate line-like structures in polyimide with submicron periodicity, which affected iPSC colony expansion, orientation of apical actin fibers, and cell division polarity. Various laser application techniques and materials were used to optimize surface patterning in terms of cell compatibility and the impact of submicron topography on pluripotent stem cells. Laser sources with pulse durations of 38 ns, 10 ps and 1 ps were used for surface structuring of semi-transparent and transparent plastic films and sheets to achieve line-like and hole-like structures. Short laser pulses (> 10 ps) and ultrashort laser pulses (< 10 ps) were suitable for precise submicron surface structuring but were affected by melting. In contrast, surface structuring with ultrashort pulses was almost free of melting. We found that iPSCs cultured on line-like structured polyimide with a periodicity of 650 nm using short pulsed and ultra-short pulsed interference structuring showed elongated cell growth while maintaining pluripotency. Polystyrene embossing also induced elongated cell growth while maintaining pluripotency. Polyimide films structured with short laser pulses of 38 ns provided the best results for cell elongation with a cell aspect ratio > 5. Finally, structuring with ultrashort laser pulses at 1 ps enabled submicron surface structuring of transparent polystyrene. Furthermore, we investigated the influence of Yes-associated protein 1 (YAP1) on the interaction with surface structures by generating and characterizing corresponding YAP1 knockout iPSC lines. Notably, YAP1 deficient iPSCs revealed similar cell morphology and colony formation as wildtype iPSCs and YAP1 is not essential to mediate the cellular response to the extracellular mechanical stimulation. In addition, the interaction of iPSCs on concentric surfaces was examined, and self-assembly from the edge of colonies was observed during the course of culture. In the course of this self-assembly, iPSC colonies eventually detached and formed cell aggregates (embryoid bodies).

Publications

• Impact of YAP on differentiation of human induced pluripotent stem cells into embryoid bodies (2020). 5th Symposium Nanoengineering for Mechanobiology, online.
  Zeevaert K., Maaßen C., Schmidt M., Elsafy Mabrouk M.H., Wagner W. & Goetzke R.
  
• Impact of YAP on differentiation of human induced pluripotent stem cells into embryoid bodies (2020). 8 th International Annual Conference of the GSCN, online.
  Zeevaert K., Goetzke R., Maaßen C., Elsafy Mabrouk M.H. & Wagner W.
  
• YAP deficiency impacts on growth of induced pluripotent stem cells on sub-μm surface topography (2021). 6th World Congress 2021, Tissue Engineering and Regenerative Medicine International Society (TERMIS), online.
  Zeevaert K., Goetzke R., He C., Pongratz L., Elsafy Mabrouk M.H., Gillner A., Reininghaus M. & Wagner W.
  
• YAP knockout suppresses early germ layer specification of human iPSC-derived embryoid bodies (2021). 10th International Meeting of the Stem Cell Network NRW, online.
  Zeevaert K., Maaßen C., Elsafy Mabrouk M.H., Schmidt M., Wagner W. & Goetzke R.
  
• YAP knockout suppresses early germ layer specification of human iPSC-derived embryoid bodies (2021). 10th International Meeting of the Stem Cell Network NRW, online.
  Zeevaert K., Maaßen C., Elsafy Mabrouk M.H., Schmidt M., Wagner W. & Goetzke R.
  
• YAP knockout suppresses early germ layer specification of human iPSC-derived embryoid bodies (2021). Annual Meeting of the International Society for Stem Cell Research (ISSCR), online.
  Zeevaert K., Maaßen C., Elsafy Mabrouk M.H., Schmidt M., Wagner W. & Goetzke R.
  
• Beam Shaping the Direct Laser Interference Patterning Spot. Journal of Laser Micro/Nanoengineering, 17(1).
  Pongratz, L. & Vannahme, K.
  
• The spatial self-organization within pluripotent stem cell colonies is continued in detaching aggregates. Biomaterials, 282, 121389.
  Elsafi, Mabrouk Mohamed H.; Goetzke, Roman; Abagnale, Giulio; Yesilyurt, Burcu; Salz, Lucia; Cypris, Olivia; Glück, Philipp; Liesenfelder, Sven; Zeevaert, Kira; Ma, Zhiyao; Toledo, Marcelo A.S.; Li, Ronghui; Costa, Ivan G.; Lampert, Angelika; Pachauri, Vivek; Schnakenberg, Uwe; Zenke, Martin & Wagner, Wolfgang
  
• YAP knockout impedes germ layer formation of human iPSC-derived embryoid bodies (2022). 13th Internal Meeting of the Stem Cell Network NRW, Herne, Germany.
  Zeevaert K., Goetzke R., Elsafy Mabrouk M.H., Schmidt M., Maaßen C., Henneke A.C., Zenke M. & Wagner W.
  
• YAP knockout suppresses early germ layer specification of human iPSC-derived embryoid bodies (2022). 6th Symposium Nanoengineering for Mechanobiology, Camogli, Italy.
  Zeevaert K., Elsafy Mabrouk M.H., Schmidt M., Maaßen C., Henneke A.C., Goetzke R. & Wagner W.
  
• YAP1 is essential for self-organized differentiation of pluripotent stem cells (2022). 10th International Annual Conference of the GSCN, Münster, Germany.
  Zeevaert K., Goetzke R., Elsafy Mabrouk M.H., Schmidt M., Maaßen C., Henneke A.C., Zenke M. & Wagner W.
  
• Epigenetic biomarkers to track differentiation of pluripotent stem cells. Stem Cell Reports, 18(1), 145-158.
  Schmidt, Marco; Zeevaert, Kira; Elsafi, Mabrouk Mohamed H.; Goetzke, Roman & Wagner, Wolfgang
  
• YAP1 is essential for self-organized differentiation of pluripotent stem cells. Biomaterials Advances, 146, 213308.
  Zeevaert, Kira; Goetzke, Roman; Elsafi, Mabrouk Mohamed H.; Schmidt, Marco; Maaßen, Catharina; Henneke, Ann-Christine; He, Chao; Gillner, Arnold; Zenke, Martin & Wagner, Wolfgang