Branched peptide‐amphiphiles as self‐assembling coatings for tissue engineering scaffolds

Abstract

An important challenge in regenerative medicine is the design of suitable bioactive scaffold materials that can act as artificial extracellular matrices. We reported previously on a family of peptide-amphiphile (PA) molecules that self-assemble into high-aspect ratio nanofibers under physiological conditions, and can display bioactive peptide epitopes along each nanofiber's periphery. One type of PA displays its epitope at a branched site using a lysine dendron, a molecular feature that improves epitope availability on the nanofiber surface. In this work, we describe the application of these branched PA (b-PA) systems as self-assembling coatings for fiber-bonded poly(glycolic acid) scaffolds. b-PAs bearing variations of the RGDS adhesion epitope from fibronectin were shown by elemental analysis to coat repeatably onto fiber scaffolds. The retention of supramolecular organization after coating on the scaffold was demonstrated through spectroscopic identification of beta-sheet structures and the close association of hydrophobic tails in a model pyrene-containing PA system. Primary human bladder smooth muscle cells demonstrated greater initial adhesion to b-PA-functionalized scaffolds than to bare scaffolds or to those coated with linear PAs. This strategy of molecular design and coating may have potential application in bladder tissue regeneration.

Single-walled carbon nanotubes promote rat vascular adventitial fibroblasts to transform into myofibroblasts by SM22-α expression

“…The tissueengineering nanomaterials, which are produced from traditional tissue-engineering materials by nanotechnology, have special biological properties and have attracted much interest. In recent years, studies on the application of nanomaterials [4][5][6][7][8][9][10][11][12] in tissue engineering fields have been of great interest. The applications of nanophase ceramics, carbon nanotubes (CNTs), carbon nanowires, and nano metallic materials in bone and cartilage tissue engineering; titanium nanomaterials, 4 poly-DL-lactide nanomaterials, [5][6][7][8] and carbon nanofibers 9,10 in artery tissue engineering; organic frameworks, 11 nanofibrous scaffolds, and CNTs/fibers in neural tissue engineering; 12 and nanostructured polymers in bladder tissue engineering have already been reported.…”

Клеточные Матрицы (Скаффолды) Для Целей Регенерации Кости: Современное Состояние Проблемы

“…В перспективе пори-стость и размеры пор матрицы спо-собны влиять in vivo на остеокондук-цию и васкуляризацию. Интеграция нативных тканей в матрицу стимули-руется через рост в коммуникацион-ные поры, таким образом, оптималь-ные и минимальные размеры пор должны формироваться в матрице для поддержки врастания тканей [16,25]. Наконец, размеры пор и пори-стость обусловливают межклеточные сигнальные взаимодействия, обеспе-чивающие остеобластную дифферен-цировку мезенхимальных стволовых клеток (МСК) и продукцию протеинов внеклеточного матрикса [6, 16,56].…”

Aspects of Urological Tissue Engineering

“…(Sargeant, 2008;Silva, 2004) Previously, PAs were used to coat PGA microfiber scaffold for the improved attachment of smooth muscle cells. (Harrington, 2006;Behanna, 2005) This PGA scaffold was submerged in a suspension of smooth muscle cells in media and modified with PA gel mixed with growth factors as a top layer for the entrapment of cells. The opposite face of the scaffold could them be modified using a second component, which in this case was a mixture of PGA and urothelial cells, since these cells could potentially send necessary signals to smooth muscle cells during regeneration.…”

“…Nanoscale roughness of biopolymers or synthetic biodegradable polymers used in bladder regeneration research can be achieved by numerous techniques including surface functionalization with nanometer-size fibers such as PAs, electrospinning, chemical etching, nano-and micromolding and more. (Harrington, 2006;Doshi, 1995; The aforementioned techniques may be applied as potential methods for the fabrication of improved scaffolds for bladder regeneration. Alternative means to achieve nanostructured membranes for bladder regeneration research utilizes micro or nanomolding.…”