title: High aspect ratio nanoimprinted grooves of poly(lactic-co-glycolic acid) control the length and direction of retraction fibers during fibroblast cell division.
abstract: Retraction fibers (RFs) determine orientation of the cell division axis and guide the spreading of daughter cells. Long and unidirectional RFs, which are especially apparent during mitosis of cells in three-dimensional (3D) environments, enable improved control over cell fate, following division. However, 3D gel environments lack the cues necessary for predetermining the orientation of RFs to direct tissue architecture. While patterning of focal adhesion regions by microcontact printing can determine orientation of the RFs through enhancing focal adhesion numbers along particular directions, the RFs remain short due to the two-dimensional culture environment. Herein, the authors demonstrate that nanoimprinted grooves of polylactic acid glycolic acid (PLGA) with a high aspect ratio (A.R. of 2.0) can provide the cues necessary to control the direction of RFs, as well as enable the maintenance of long and unidirectional RFs as observed within 3D cultures, while the same is not possible with PLGA grooves of lower A.R. (1.0 or lower). Based on enhanced levels of contact guidance of premitotic fibroblast protrusions at high A.R. grooves and deeper levels of focal adhesion due to filopodia extensions into these grooves, it is suggested that submicron (800 nm width) PLGA grooves with A.R. of 2 are capable of supporting mechanical forces from cell protrusions to a greater depth, thereby enabling the maintenance of the protrusions as long and unidirectional RFs during cell division. Given the scalability and versatility of nanoimprint techniques, the authors envision a platform for designing nanostructures to direct tissue regeneration and developmental biology.
authors.affiliation: Institute of Physics, Academia Sinica, Taipei 11529, Taiwan and Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904.
authors.forename: Yi-Hsuan
authors.initials: YH
authors.lastname: Su
authors.affiliation: Institute of Physics, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Po-Chieh
authors.initials: PC
authors.lastname: Chiang
authors.affiliation: Institute of Physics, Academia Sinica, Taipei 11529, Taiwan and School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331.
authors.forename: Li-Jing
authors.initials: LJ
authors.lastname: Cheng
authors.affiliation: Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan and Institute of Biophotonics, National Yang-Ming University, Taipei 11221, Taiwan.
authors.forename: Chau-Hwang
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904.
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Swami
authors.affiliation: Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan; and Genomics Research Center, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Chia-Fu
authors.initials: CF
authors.lastname: Chou
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects*; D022081:Cell Surface Extensions / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects* / Q000502:physiology*; D019344:Lactic Acid / Q000378:metabolism*; D051379:Mice; D041681:NIH 3T3 Cells; D049329:Nanostructures; D011100:Polyglycolic Acid / Q000378:metabolism*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013499:Surface Properties
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid