Functional fabrication of recombinant human collagen–phosphorylcholine hydrogels for regenerative medicine applications

Abstract

The implant-host interface is a critical element in guiding tissue or organ regeneration. We previously developed hydrogels comprising interpenetrating networks of recombinant human collagen type III and 2-methacryloyloxyethyl phosphorylcholine (RHCIII-MPC) as substitutes for the corneal extracellular matrix that promote endogenous regeneration of corneal tissue. To render them functional for clinical application, we have now optimized their composition and thereby enhanced their mechanical properties. We have demonstrated that such optimized RHCIII-MPC hydrogels are suitable for precision femtosecond laser cutting to produce complementing implants and host surgical beds for subsequent tissue welding. This avoids the tissue damage and inflammation associated with manual surgical techniques, thereby leading to more efficient healing. Although we previously demonstrated in clinical testing that RHCIII-based implants stimulated cornea regeneration in patients, the rate of epithelial cell coverage of the implants needs improvement, e.g. modification of the implant surface. We now show that our 500μm thick RHCIII-MPC constructs comprising over 85% water are suitable for microcontact printing with fibronectin. The resulting fibronectin micropatterns promote cell adhesion, unlike the bare RHCIII-MPC hydrogel. Interestingly, a pattern of 30μm wide fibronectin stripes enhanced cell attachment and showed the highest mitotic rates, an effect that potentially can be utilized for faster integration of the implant. We have therefore shown that laboratory-produced mimics of naturally occurring collagen and phospholipids can be fabricated into robust hydrogels that can be laser profiled and patterned to enhance their potential function as artificial substitutes of donor human corneas.

Human Bone Derived Collagen for the Development of an Artificial Corneal Endothelial Graft. In Vivo Results in a Rabbit Model

“…In recent years, several groups have been using natural [25–27] or recombinant [28] collagen scaffolds for the culture of human CECs, being porcine [29] or bovine [30,31] type I collagen the most widely used.…”

3D Bioprinting of Tissue/Organ Models

“…[142] 3D printing was utilized to fabricate the physical model for use in research on fundus range viewing.I na ne ffort to produce mimics of human corneas in the laboratory,n aturally occurring collagen and phospholipids have been bioprinted into robust hydrogels that were laser profiled and patterned to enhance their potential function as artificial substitutes of donor human corneas. [143] 3.4.7. Bioprinted Ear Ab ionic ear has been developed by 3D bioprinting of ac ell-seeded hydrogel matrix in the anatomic geometry of ah uman ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles.…”

“…Genomic and proteomic screening methods are often used to identify classes of genes or proteins that are differentially expressed in different maturation stages of tissue/organ model development or in vitro disease model progression. [105,110,141,143,163] Differentiation of stem cells into particular lineages has also been evaluated by genomic and proteomic analysis. [110,115] Evaluation of the function of an engineered tissue can also be carried out by estimating target proteins ( Figure 4B).…”

3D‐Biodruck von Gewebe‐ und Organmodellen

“…Das durch 3D‐Druck hergestellte Modell kam in Augengrund‐Studien zum Einsatz. Bei einem Versuch, die Hornhaut des menschlichen Auges im Labor nachzubauen, wurden Kollagen und Phospholipide in robuste Hydrogele gedruckt, die durch Laserbehandlung gemustert worden waren und als künstlicher Ersatz für Spender‐Hornhaut dienten …”