1
|
Holland G, Pandit A, Sánchez-Abella L, Haiek A, Loinaz I, Dupin D, Gonzalez M, Larra E, Bidaguren A, Lagali N, Moloney EB, Ritter T. Artificial Cornea: Past, Current, and Future Directions. Front Med (Lausanne) 2021; 8:770780. [PMID: 34869489 PMCID: PMC8632951 DOI: 10.3389/fmed.2021.770780] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022] Open
Abstract
Corneal diseases are a leading cause of blindness with an estimated 10 million patients diagnosed with bilateral corneal blindness worldwide. Corneal transplantation is highly successful in low-risk patients with corneal blindness but often fails those with high-risk indications such as recurrent or chronic inflammatory disorders, history of glaucoma and herpetic infections, and those with neovascularisation of the host bed. Moreover, the need for donor corneas greatly exceeds the supply, especially in disadvantaged countries. Therefore, artificial and bio-mimetic corneas have been investigated for patients with indications that result in keratoplasty failure. Two long-lasting keratoprostheses with different indications, the Boston type-1 keratoprostheses and osteo-odonto-keratoprostheses have been adapted to minimise complications that have arisen over time. However, both utilise either autologous tissue or an allograft cornea to increase biointegration. To step away from the need for donor material, synthetic keratoprostheses with soft skirts have been introduced to increase biointegration between the device and native tissue. The AlphaCor™, a synthetic polymer (PHEMA) hydrogel, addressed certain complications of the previous versions of keratoprostheses but resulted in stromal melting and optic deposition. Efforts are being made towards creating synthetic keratoprostheses that emulate native corneas by the inclusion of biomolecules that support enhanced biointegration of the implant while reducing stromal melting and optic deposition. The field continues to shift towards more advanced bioengineering approaches to form replacement corneas. Certain biomolecules such as collagen are being investigated to create corneal substitutes, which can be used as the basis for bio-inks in 3D corneal bioprinting. Alternatively, decellularised corneas from mammalian sources have shown potential in replicating both the corneal composition and fibril architecture. This review will discuss the limitations of keratoplasty, milestones in the history of artificial corneal development, advancements in current artificial corneas, and future possibilities in this field.
Collapse
Affiliation(s)
- Gráinne Holland
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
| | - Abhay Pandit
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
| | - Laura Sánchez-Abella
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Andrea Haiek
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Iraida Loinaz
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Damien Dupin
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | | | | | - Aritz Bidaguren
- Ophthalmology Department, Donostia University Hospital, San Sebastián, Spain
| | - Neil Lagali
- Department of Biomedical and Clinical Sciences, Faculty of Medicine, Linköping University, Linköping, Sweden
| | - Elizabeth B. Moloney
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
| | - Thomas Ritter
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
| |
Collapse
|
2
|
Blum O, Haiek A, Cwikel D, Dori Z, Meade TJ, Gray HB. Isolation of a myoglobin molten globule by selective cobalt(III)-induced unfolding. Proc Natl Acad Sci U S A 1998; 95:6659-62. [PMID: 9618468 PMCID: PMC22589 DOI: 10.1073/pnas.95.12.6659] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Reaction of the Schiff-base complex [Co(acetylacetonate-ethylenediimine)(NH3)2]+ with metmyoglobin at pH 6.5 yields a partially folded protein containing six Co(III) complexes. Although half of its alpha-helical secondary structure is retained, absorption and CD spectra indicate that the tertiary structure in both B-F and AGH domains is disrupted in the partially folded protein. In analogy to proton-induced unfolding, it is likely that the loss of tertiary structure is triggered by metal-ion binding to histidines. Cobalt(III)-induced unfolding of myoglobin is unique in its selectivity (other proteins are unaffected) and in allowing the isolation of the partially folded macromolecule (the protein does not refold or aggregate upon removal of free denaturant).
Collapse
Affiliation(s)
- O Blum
- Beckman Institute 139-74, California Institute of Technology, Pasadena, CA 91125, USA
| | | | | | | | | | | |
Collapse
|