Tailoring the Interface of Biomaterials to Design Effective Scaffolds

Abstract

Tissue engineering (TE) is a multidisciplinary science, which including principles from material science, biology and medicine aims to develop biological substitutes to restore damaged tissues and organs. A major challenge in TE is the choice of suitable biomaterial to fabricate a scaffold that mimics native extracellular matrix guiding resident stem cells to regenerate the functional tissue. Ideally, the biomaterial should be tailored in order that the final scaffold would be (i) biodegradable to be gradually replaced by regenerating new tissue, (ii) mechanically similar to the tissue to regenerate, (iii) porous to allow cell growth as nutrient, oxygen and waste transport and (iv) bioactive to promote cell adhesion and differentiation. With this perspective, this review discusses the options and challenges facing biomaterial selection when a scaffold has to be designed. We highlight the possibilities in the final mold the materials should assume and the most effective techniques for its fabrication depending on the target tissue, including the alternatives to ameliorate its bioactivity. Furthermore, particular attention has been given to the influence that all these aspects have on resident cells considering the frontiers of materiobiology. In addition, a focus on chitosan as a versatile biomaterial for TE scaffold fabrication has been done, highlighting its latest advances in the literature on bone, skin, cartilage and cornea TE.

XRD and IR revelation of a unique g-C3N4 phase with effects on collagen/hydroxyapatite bone scaffold pore geometry and stiffness

“…Bone tissue engineering is the field of regenerative medicine where damaged or a diseased bone is repaired by restoring new tissue using engineered scaffolds, stem cells and biomolecules [1][2][3]. The most successful scaffolds are fabricated from biomaterials that imitate the human extracellular matrix (ECM) more successfully [4][5][6]. Stem cells can be harvested from the patient's own body and seeded on the scaffold with the supply of biomolecules (nutrients) needed by the cells [7].…”

“…Therefore, sustaining a balance between the optimum pore size and specific surface area for cell adhesion and differentiation is vital for scaffold design [20]. The choice of appropriate materials to sustain a balance is a major challenge since pore volume has an inverse relation to stiffness [6]. However, researchers are incorporating minerals (like Fe, Mn) to enhance scaffold stiffness [21].…”

Balancing biological and biomechanical performance in intervertebral disc repair: a systematic review of injectable cell delivery biomaterials

“…AF repair strategies have more often involved devices like the X-Close (Bailey et al, 2013) and Barricaid (Parker et al, 2016) systems that are designed to close AF defects and prevent reherniation. Additionally, fibre-reinforced tissue engineered constructs to plug AF defects (Sato et al, 2003) or recapitulate the organised collagen structure of the AF (Bhattacharjee et al, 2012;Nerurkar et al, 2007;Park et al, 2012) have also been investigated for AF repair, yet they are not injectable. Injectable cell delivery strategies for AF repair and regeneration are compelling because reherniation and recurrent pain remains an unmet clinical need, and because injectable formulations may be applied rapidly during discectomy, or other minimally invasive procedures.…”

“…Zhou et al reported that increasing genipin additional crosslinker concentration from 0.01 % to 1 % w/v decreased viability and NPC differentiation capacity, but increased Young's modulus (Zhou et al, 2018a). Park et al found that incorporating higher concentrations of silk into their biomaterial reduced chondrogenic gene expression and ECM synthesis while increasing Young's modulus (Park et al, 2012). Several mechanisms can explain this 'seesaw' phenomenon.…”

Crosslinker concentration controls TGFβ-3 release and annulus fibrosus cell apoptosis in genipin-crosslinked fibrin hydrogels

“…5 ). Cell-matrix interactions are important for a variety of integrin-mediated signalling ( Giancotti and Ruoslahti, 1999 ); thus, facilitating interactions between encapsulated cells and the biomaterial carrier is a critical design requirement for tissue engineering strategies ( Parisi et al , 2018 ). Disruption of cell-matrix contacts in anchorage-dependent cells induces apoptosis and this phenomenon is termed anoikis ( Frisch and Ruoslahti, 1997 ).…”