Page 129 - IJB-10-2

International Journal of Bioprinting 3D bioprinting for corneal regeneration

Table 2. Tissue engineering approaches for corneal replacement
Corneal Clinical status Biopolymer used Results References
replacement
Full thickness In vitro study Acellular porcine Fully transparent; 91,104
cornea and in vivo cornea suture retention (5 Newton) near to NPC (6 Newton);
experiment tier resistance (3.42 Newton) lower than NPC (5.35 Newton);
on rabbit cell-loaded APC repaired alkali corneal burn on rabbit
Full thickness Animal model: Collagen-chitosan Fully transparent after transplantation; 91,105
cornea pig hydrogels visible light transmittance (>90%) better than native human cornea
(~80%);
light scatter lower than the human cornea;
100% suturable
Full thickness In vitro study Fibrin-agarose Different cells proliferate in hydrogel; 91,106
cornea hydrogels epithelial cells formed normal, several-layer epithelia;
high expression of vimentin and cytokeratin;
similar structure to the native cornea by SEM
Full thickness Phase I clinical Cross-linked 10 patients (8 male, 2 female); 91,107
cornea trial: human recombinant human 500 µm thick biosynthetic corneal scaffold;
type III collagen sutures were removed 6.5 weeks after implantation;
no pain or discomfort;
complete epithelization in about 2.5 months
4 years of Optical clarity was higher (95.1%) than human cornea (>87%); 91,108
follow-up water content 91.5% (cornea: 78%);
no significant biodegradation;
mechanical strength was lower than the cornea;
tensile strength: 0.286 MPa (cornea: 3.81 MPa);
modulus: 1.749 MPa (cornea: 3–13 MPa);
only 1 rejection was reported
Epithelial tissue In vitro study Heat-sensitive cell Directly transplantation without suture; 91,109
and Clinical culture for tissue- re-epithelization within 1 week;
study with 4 engineered oral transparent during 14-month follow-up;
human patients mucosal epithelial cell no complication
sheets
Animal model: Automated cell culture Cell viability 93.6%, growth in multilayer; 91,110
rabbit system for epithelial culturing time: 2 weeks;
sheet scaffold prepa- 10 times medium change with an automated system;
ration fully transparent sheet 1 week after transplantation;
no adverse effect
Epithelial tissue In vitro study Silk foil with pattern Silk produced by Bombyx mori on a patterned silicon layer; 91,111
HCLEs had better culturing conditions on silk sheets;
better vinculin and actin production
Epithelial tissue In vitro study Rat-tail Type I Cells seeded on cell-loaded hydrogel with crypted surface; 91,112
collagen hydrogel cells were able to proliferate;
7 layers produced by cells;
different epithelial markers expressed
Epithelial tissue In vitro study Rat-tail Type I Cell-embedded in compressed collagen hydrogel; 91,113
collagen hydrogel morphology similar to the amniotic membrane observed with SEM;
the gel was mechanically dense and strong;
the peripheral region showed more proliferative capacity than the
central;
higher cytokeratin and collagen expression than on amniotic
membrane
Epithelial tissue In vitro study Chemically 80–90% transmittance of dendrimer cross-linked collagen; 91,114
cross-linked modulus: 1.4–5.3 MPa (in the range of natural human cornea);
collagen hydrogel cells proliferated in hydrogel and remained viable
(Continued)

Volume 10 Issue 2 (2024) 121 doi: 10.36922/ijb.1669