Preparation of scaffolds from human hair proteins for tissue-engineering applications

Abstract

Human hair proteins were isolated and purified for the fabrication of tissue-engineering scaffolds. Their cellular compatibility was studied using NIH3T3 mice fibroblast cells. The proteins were characterized using FTIR spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis for molecular weights and two-dimensional polyacrylamide gel electrophoresis for their isoelectric points (pIs). The molecular weights of keratins were in the range of 40-60 kilo-Daltons (kDa) and of matrix proteins were in the range of 15-30 kDa. The pIs of keratins were found to be in the range of 4.5-5.3. Sponges of the proteins were formed by lyophilization. Scanning electron microscopy was performed to examine the surface. Swelling studies were carried out in phosphate buffer saline at physiological pH 7.4. The hydrophilic character of the protein surface was studied by determining an average contact angle, which came to be 37 degrees. The wells of tissue culture plates were coated with these proteins for studying the attachment and morphology of the cells. The protein detachment study was done to ensure the adsorption of proteins on the wells until the completion of the experiments. The cellular growth on a protein-coated surface showed three-dimensional 'bulged' morphology due to cell-cell and cell-matrix contacts. The sponges of human hair proteins supported more cells for a longer period than control. The morphology and cell proliferation studies exhibited by NIH3T3 cells on these proteins have shown their potential to be used as tissue-engineering scaffolds with better cell-cell contacts and leucine-aspartic acid-valine (LDV)-mediated cell-matrix interactions.

Photochemical crosslinking of soluble wool keratins produces a mechanically stable biomaterial that supports cell adhesion and proliferation

“…A recent study exploring uncrosslinked materials formed from human hair proteins reported that 100% of fibroblasts seeded onto the gels were attached after 6 h. This rapid and effective cell adhesion was attributed to the presence of cell binding motifs, 12 which we detected in three of the proteins present in our wool extract (Table II and Fig. 1).…”

Ciprofloxacin-Loaded Keratin Hydrogels PreventPseudomonas aeruginosaInfection and Support Healing in a Porcine Full-Thickness Excisional Wound

“…18 Keratins can be formulated into a variety of dressing materials including foams, sponges, and hydrogels. [19][20][21][22] Specifically, keratin hydrogels are advantageous over alternative dressings because they elicit minimal foreign body responses, possess tunable mechanical properties, and are capable of serving as sustained-release delivery vehicles. 18,22,23 Additionally, keratins are unique as antibiotic carriers for infection control in that they are susceptible to enzymatic degradation by cutaneous bacteria that produce keratinases.…”

Human keratin hydrogels support fibroblast attachment and proliferation in vitro

“…These keratin solutions are capable of polymerizing to form hydrogels that have been used successfully in vivo as a physical barrier to prevent the infiltration of inflammatory cells following cell transplantation (Nakaji-Hirabayashi et al 2008) and also as an internal haemostat (Aboushwareb et al 2009;Hill et al 2010). Although keratins belong to the family of intermediate filaments that are intracellular cytoskeleton proteins (Szeverenyi et al 2008), they contain the cell adhesion motif LDV (leu-asp-val), which is recognized by α 4 β 1 integrin (Makarem and Humphries 1991), suggesting that keratins can function as an extracellular substrate for cell attachment and subsequently can support cell growth and development (Verma et al 2008). Indeed, Sierpinski et al (2008) have shown that keratin hydrogels can enhance nerve regeneration in vivo.…”