Polyelectrolyte Complex Membranes for Specific Cell Adhesion

Abstract

The presentation of bioactive ligands on biomaterial surfaces is often confounded by the adsorption of proteins present in the biological milieu, rendering any type of cellular response nonspecific. We have engineered a polyelectrolyte complex membrane that demonstrates specific adhesion of various cell types for both two-dimensional (2D) and three-dimensional (3D) cell culture systems. Specific cell adhesion is achieved by a three-tiered structure: a silica cross-linked polycation as the bottom (first) tier, a nonfouling polyanion-poly(ethylene glycol) (PEG) conjugate as the intermediate (second) tier, and the cell-adhesion ligand as the top (third) tier. Each tier of the membrane was characterized in terms of chemical composition and dimensions. Epithelial cells (primary human cortical renal cells and a hepatocellular carcinoma cell line) cultured on the membranes exhibited little cell attachment on the polyanion-PEG second tier and good cell adhesion on the RGD-modified third tier. Thus, the second tier allowed the effect of cell adhesion due to the ligand (third tier) to be isolated and distinguished from nonspecific cell attachment to the first tier. For the culturing of cells in three dimensions, the three-tiered membrane system was applied using a highly swellable chitosan membrane as the first tier. The resulting cell-membrane construct was uniformly dispersed and centrifuged to form a matrix that interacted intimately with cells in the form of a pellet. Presentation of RGD in the latter format enhanced the viability of human mesenchymal stem cells (hMSCs) over controls without RGD.

Effects of electrode surface modification with chlorotoxin on patterning single glioma cells

“…The glioma cells patterned on the substrates with covalently-bound CTX demonstrated cell morphology extended beyond the gold electrodes (Fig 5b–c). Similar cell morphology was also observed when 9L glioma cells were patterned on substrates where gold electrodes were functionalized using the common cell adhesion ligands, such as chitosan, fibronectin, poly-L-lysine, and RGD 22, 23 (Fig. S1 in ESI).…”

In vivo bioactivity of rhBMP-2 delivered with novel polyelectrolyte complexation shells assembled on an alginate microbead core template

“…Polyelectrolyte complexes (PEC) formed by the electrostatic interactions of cations and anions have been attracting attention as "growth factor repositories" mainly because of the feasibility of tailoring their physicochemical properties and composition. For example: PEC microspheres, [1] membranes, [2] nanotubes, [3] nanoparticles, [4] fibers, [2] and coarcevates [5] have been developed based on different polysaccharides [4] and polyamines [6,7]. These have been used for core encapsulation [8], surface adsorption [9], and matrix entrapment [10] of different biomolecules and cells including, proteins, enzymes and stem cells [2,10,11].…”

“…For example: PEC microspheres, [1] membranes, [2] nanotubes, [3] nanoparticles, [4] fibers, [2] and coarcevates [5] have been developed based on different polysaccharides [4] and polyamines [6,7]. These have been used for core encapsulation [8], surface adsorption [9], and matrix entrapment [10] of different biomolecules and cells including, proteins, enzymes and stem cells [2,10,11]. In particular, immobilization and delivery of nano-scale sized biomolecules such as peptides and DNA plasmids have been highly successful with this approach [12].…”

Modification of chitosan membrane with poly(vinyl alcohol) and biocompatibility evaluation

“…CS [poly (1,4),-␤-d-glucopyranosamine] is the second abundant natural polysaccharide, which has many useful properties: nontoxicity, biocompatibility, biodegradability, bioactivity, antibacterial, excellent film forming capacity [12][13][14]. Thus CS is widely used in a number of biomedical applications including drug delivery systems [15,16], tissue engineering [17,18], wound dressing [19].…”