Biomimetic Bilayered Scaffolds for Tissue Engineering: From Current Design Strategies to Medical Applications

Abstract

Tissue damage due to cancer, congenital anomalies, and injuries needs new efficient treatments that allow tissue regeneration. In this context, tissue engineering shows a great potential to restore the native architecture and function of damaged tissues, by combining cells with specific scaffolds. Scaffolds made of natural and/or synthetic polymers and sometimes ceramics play a key role in guiding cell growth and formation of the new tissues. Monolayered scaffolds, which consist of uniform material structure, are reported as not being sufficient to mimic complex biological environment of the tissues. Osteochondral, cutaneous, vascular, and many other tissues all have multilayered structures, therefore multilayered scaffolds seem more advantageous to regenerate these tissues. In this review, recent advances in bilayered scaffolds design applied to regeneration of vascular, bone, cartilage, skin, periodontal, urinary bladder, and tracheal tissues are focused on. After a short introduction on tissue anatomy, composition and fabrication techniques of bilayered scaffolds are explained. Then, experimental results obtained in vitro and in vivo are described, and their limitations are given. Finally, difficulties in scaling up production of bilayer scaffolds and reaching the stage of clinical studies are discussed when multiple scaffold components are used.

Extracellular Matrix‐Bioinspired Anisotropic Topographical Cues of Electrospun Nanofibers: A Strategy of Wound Healing through Macrophage Polarization

“…[27] Elastin provides 1000 times more flexibility than collagen, giving it sufficient mechanical strength for elasticity. [28] FN is a glycoprotein with a high molecular weight of ≈500 kDa, consisting of two nearly identical subunits that combine to form a dimeric molecule. [19,29] The main function of FN is to facilitate cell adhesion to the extracellular matrix and promote cell migration.…”

“…[ 27 ] Elastin provides 1000 times more flexibility than collagen, giving it sufficient mechanical strength for elasticity. [ 28 ]…”

Designing biomimetic scaffolds for skin tissue engineering

“…Last but not least, considering that cells, growth factors, and other molecules are exposed to adverse conditions during the manufacturing process, suitable preparation time and experimental environment are required. 257 Moreover, other aspects (e.g., related labor setups and equipment, necessary time, and the total cost of materials and biomanufacturing process) should be taken into consideration. 258…”

Three‐dimensional multicellular biomaterial platforms for biomedical application

“…[112][113][114] After decades of development, biological scaffolds have been derived into various types and preparation methods. Traditional preparation methods such as freeze-drying, [115] electrostatic spinning, [108] gas foaming, [116] particle leaching, [115] and other technologies have been widely used in the preparation of biological scaffolds. These methods are often used to prepare biological scaffolds with interconnect gaps.…”