Dairy-Inspired Coatings for Bone Implants from Whey Protein Isolate-Derived Self-Assembled Fibrils.

Ute Hempel,Jenny Aveyard,Laurine Martocq,Julia K Keppler,Timothy E L Douglas,Rebecca Rabe

doi:10.3390/ijms21155544

Abstract

To improve the integration of a biomaterial with surrounding tissue, its surface properties may be modified by adsorption of biomacromolecules, e.g., fibrils. Whey protein isolate (WPI), a dairy industry by-product, supports osteoblastic cell growth. WPI’s main component, β-lactoglobulin, forms fibrils in acidic solutions. In this study, aiming to develop coatings for biomaterials for bone contact, substrates were coated with WPI fibrils obtained at pH 2 or 3.5. Importantly, WPI fibrils coatings withstood autoclave sterilization and appeared to promote spreading and differentiation of human bone marrow stromal cells (hBMSC). In the future, WPI fibrils coatings could facilitate immobilization of biomolecules with growth stimulating or antimicrobial properties.

Highlights

Whey protein isolate (WPI) is a dairy industry by-product which contains > 95% protein, of which 75% is β-lactoglobulin [1]
Previous studies showed that WPI enhances cell proliferation and osteogenic differentiation and displays antibacterial properties [1,2,3]
Better cell-biomaterial interactions and biomaterial integration into host tissue can be achieved by improving surface properties, e.g., by coatings

Summary

Introduction

Whey protein isolate (WPI) is a dairy industry by-product which contains > 95% protein, of which 75% is β-lactoglobulin [1]. A commonly used fibrillar molecule used as implant coating materials is collagen, which is known to promote cell adhesion, spreading and proliferation [14,15,16,17,18]. The fibrillar coating promoted the adhesion and re-organization of the cytoskeleton of hBMSC, did not influence the number of adherent cells, but obviously improved their “quality”, as evidenced by higher TNAP activity. There is a whole range of conditions that can be used to alter the morphology and to study the correlation between structure and cell behavior in the future Another focus of future work will be the extension of the cell biological characterization of the coatings, to elucidate the exact mechanism by which coatings may promote differentiation, and to include cell-induced mineralization. WPI fibrillar coatings should be compared to more commonly used fibrillar coatings of fibronectin and collagen, which are known to promote cell adhesion [14,15,16,17,18,19,20]

Materials and Methods

Findings

Conclusions