title: Femtosecond laser ablation enhances cell infiltration into three-dimensional electrospun scaffolds.
abstract: Electrospun scaffolds are used extensively in tissue-engineering applications as they offer a cell-friendly microenvironment. However, one major limitation is the dense fibers, small pore size and consequently poor cell infiltration. Here, we employ a femtosecond (FS) laser system to ablate and create microscale features on electrospun poly(L-lactide) (PLLA) nanofibrous scaffolds. Upon determining the ablation parameters, we pattern structured holes with diameters of 50, 100 and 200 μm and spacings of 50 and 200 μm between adjacent holes on the scaffolds. The elastic moduli of ablated scaffolds decrease with the decrease in spacing and the increase in hole size. Cells seeded on the laser-ablated scaffolds exhibit different morphology but similar proliferation rate when compared with control (non-ablated) scaffold. Furthermore, animal studies indicate that ablated scaffolds facilitate endothelial cell ingrowth as well as drastically increase M2 macrophage and overall cell infiltration. These findings demonstrate that FS laser ablation can be used to increase cell infiltration into nanofibrous scaffolds. Laser ablation not only can create desired features in micrometer length scale but also presents a new approach in the fabrication of three-dimensional porous constructs for tissue engineering.
authors.affiliation: Graduate Program in Bioengineering, University of California, Berkeley, 94720, USA.
authors.forename: Benjamin Li-Ping
authors.initials: BL
authors.lastname: Lee
authors.forename: Hojeong
authors.initials: H
authors.lastname: Jeon
authors.forename: Aijun
authors.initials: A
authors.lastname: Wang
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yan
authors.forename: Jian
authors.initials: J
authors.lastname: Yu
authors.forename: Costas
authors.initials: C
authors.lastname: Grigoropoulos
authors.forename: Song
authors.initials: S
authors.lastname: Li
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D057139:Nanofibers / Q000737:chemistry / Q000648:ultrastructure; D011091:Polyesters / Q000494:pharmacology; D016062:Porosity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C033616:poly(lactide)