Tissue-Engineered Recombinant Human Collagen-Based Corneal Substitutes for Implantation: Performance of Type I versus Type III Collagen

Abstract

Both RHC-I and -III implants can be safely and stably integrated into host corneas. The simple cross-linking methodology and recombinant source of materials makes them potentially safe and effective future corneal matrix substitutes.

Dental Pulp Tissue Engineering in Full-length Human Root Canals

“…The development of human recombinant collagen (rhCollagen) matrices is attractive from a translational standpoint because they are potentially safer than animal collagen and because they enable a crosstalk to occur between cells and extracellular matrix from the same species. Indeed, rhCollagen type I scaffold has shown promising results when used for bone and corneal regeneration (Yang et al, 2004;Merrett et al, 2008). Here, we tested the suitability of injectable scaffolds (i.e., Puramatrix™, rhCollagen type I) for dental pulp tissue engineering using SHED transplanted into full-length root canals of human premolars.…”

Limbal Stem Cell Transplantation and Corneal Neovascularization

“…When confluent, the epithelial sheet is transferred to the ocular surface using either a contact lens or fibrin gel (Pellegrini et al, 1997, Pellegrini et The cells cultured on the lotrafilcon A contact lenses proliferated, migrated, showed a corneal phenotype and microvillae on the apical surface; whereas cells cultured on balafilcon A contact lenses showed no growth (Di Girolamo et al, 2007). Various substrates have been used in suspension culture systems for proliferation of limbal epithelial cells, for example, reconstituted collagen substrate membrane from HAM (Merrett et al, 2008), a chitosan cross-linked collagen membrane (Auxenfans et al, 2009), which has good adherence, retains epithelial morphology and supports the nontoxic nature of the membrane. Reconstituted human amniotic collagen membrane has been used to act as collagen scaffolding for the culture of limbal epithelial cells (Doillon et al, 2003, Griffith et al, 1999, Li et al, 2005.…”

Artificial corneas: a regenerative medicine approach

“…There was also ingrowth of stromal cells and corneal sensory nerves. 21,22 The advantage of RHC is that it is produced synthetically in yeast and therefore avoids the risk of disease transmission from animal-extracted collagen and possible immune response. Although properties of both RHCI and RHCIII were fairly similar, the optical properties of RHCIII were better and showed a trend towards higher mechanical strength.…”

“…Hydrogels with starting RHC concentrations of 13.7% yielded constructs with mechanical properties of up to 1.7 MPa tensile strength with type III recombinant human collagen, with 14% elongation at break and an elastic modulus of about 20 MPa. 21 The human cornea by comparison is 3.8 MPa in tensile strength, 21 with an elastic modulus of 3-13 MPa. 21 We also noted that the remodelling of the pig corneas had occurred and the cornea stromas at 12 months postoperative show a lamellar arrangement at both light and TEM levels.…”

“…21 The human cornea by comparison is 3.8 MPa in tensile strength, 21 with an elastic modulus of 3-13 MPa. 21 We also noted that the remodelling of the pig corneas had occurred and the cornea stromas at 12 months postoperative show a lamellar arrangement at both light and TEM levels.…”