Polypeptide resurfacing method improves fibroblast's adhesion to hyaluronan strands

Abstract

Hyaluronic acid (hyaluronan, HyA) is a matrix component that takes part in cell adhesion and growth in normal and repaired tissues. Since it is soluble in water, HyA has been of limited use in tissue engineering of artificial matrices. Recent studies demonstrate that polypeptides have the twin advantages of reducing solubility of HyA and improving cellular attachment via cell surface adhesion molecule receptors. This paper describes a new approach of using a polypeptide resurfacing method to enhance the attachment of cells to HyA strands. HyA strands were crosslinked by glutaraldehyde and then resurfaced with poly-D-lysine, poly-L-lysine, glycine, or glutamine. After inoculation with fibroblasts in vitro, modified HyA was evaluated with histological and immunohistochemical staining methods for cell adhesion and proliferation. Modified HyA with fibroblast cells also were implanted in vivo. The results show that (1) both polylysines enhanced fibroblast adhesion to crosslinked HyA strands; (2) HyA strands were able to be crosslinked well by 3 days of treatment in glutaraldehyde, and as a biomaterial they could resist biodegradation; (3) modified HyA has good biocompatibility, both in vitro and in vivo. The results demonstrate that HyA material resurfaced by polypeptides has positive advantages for cellular adhesion. Resurfaced HyA has much potential as an improved biomaterial for clinical usage.

Biocompatibility and stability of disulfide-crosslinked hyaluronan films

“…Importantly, no additional crosslinkers were added to accomplish this gelation. In other cases, the small, potential cytotoxic crosslinking agents have been employed and the HA-derived materials required extensive washing or extraction to remove traces of unreacted reagents and byproducts [6,11,13].…”

“…Conversely, this feature endows thiolated HA films with considerable potential as barriers to prevent the formation of post-operative adhesions. The coating of thiolated HA films with poly D-lysine greatly improved cell attachment and proliferation, since poly D-lysine creates a positively charged surface [6] that enhances cell attachment [33,34].…”

“…However, the poor biomechanical properties of this soluble, viscoelastic natural polymer and its rapid degradation in vivo preclude many clinical applications. In order to obtain materials that are more mechanically robust and metabolically stable, a variety of hydrophobic modifications and chemical crosslinking strategies have been explored to produce insoluble or gel-like HA materials [3][4][5][6][7][8][9][10][11][12]. However, the crosslinking agents are often relatively cytotoxic small molecules, and the HA-derived materials have to be extracted or washed extensively to remove traces of unreacted reagents and byproducts [11,13].…”

Disulfide‐crosslinked hyaluronan–gelatin sponge: Growth of fibrous tissue in vivo

“…5 These limitations are also evident in films, gels, and sponges derived from crosslinked HA in the absence of any addition components. Here, we described the preparation of a synthetic mimic of the ECM in which gelatin and HA are both chemically modified with pendant thiol groups, and then oxidatively co-crosslinked in three gelatin:HA ratios to form hydrogels.…”

“…HA can be chemically and structurally modified to suit the desired application, [3][4][5][6][7] is nonimmunogenic, and can be degraded by noninflammatory natural clearance mechanisms. 8 Most chemically modified HA derivatives used for tissue engineering or tissue augmentation, however, are 'monolithic' in that no reactive groups remain for further crosslinking.…”