Table 1 Some substrates used for in vitro expansion of corneal endothelial cells (CECs)

Biological substrates

Decellularized human corneal stroma

Support formation of confluent CE monolayer, and the maintenance of the CE phenotype

[118]

Denuded Descemet's membrane (DM)

The denuded DM + CE construct rolls in the opposite direction (with CE inwards) than the CE + DM lamella (with CE outside) in solution, which complicates Tx. Tested on human primary CECs

[119]

Human amniotic membrane (HAM)

A non-immunogenic carrier, composed of collagen 4, which supports CEC proliferation and differentiation. The semi-transparent nature and variable quality of the tissue limit the use of HAM for the purpose of Tx. Moreover, in rabbit eyes edema was observed seven days after Tx of CE grown on HAM

[73]

Decellularized human lens capsule (DHLC)

Composed of collagens (1, 3, 4, 8), laminin and fibronectin. Facilitates CECs’ expansion and sustains the endothelial phenotype. DHLC + CE construct has a good adherence to posterior stroma after Tx. In solution rolls with CE inwards

[119, 120]

Culture plate coatings

Collagen 1 or 4

Main proteins in the human cornea. Improve attachment and morphology of primary CECs; supposed to maintain the normal phenotype of CECs and prevent phenotypic change. Handling of soft collagen-based substrates may be improved by a cross-linking the collagen fibers

[62]

Laminin 5

Promotes adhesion, migration, and proliferation of human primary CECs (donor age: 55–76 years), and supports wound healing of injured CEC

[121]

Laminin-511, -521

Enhance adhesion, proliferation, and differentiation of human primary CECs (donor age: > 40 years)

[122]

Laminin E8 fragments

Support human CECs’ expansion with a similar efficacy to that obtained with laminins-511/-521. Recombinant laminin fragments can be produced more easily than full-length laminins

[53, 122]

FNC coating mix ® (fibronectin + collagen 1 + albumin)

Improves rapid attachment of primary human CECs and reduces cell loss due to rinsing of cells. Accelerating the CECs’ attachment more significantly than collagen I

[40, 45]

(Bio)synthetic substrates

Collagen 4 + laminin-coated collagen 1

Supports the formation of confluent CE monolayers (human and bovine primary CECs) and the maintenance of the CE phenotype

[123]

Poly (lactic-co-glycolic acid)

Preserves morphology and high cell viability (on smaller fibers with smaller interstitial space); tested on HCEC-12 cell line

[61, 124]

Poly-ε-lysine (pεK) cross-linked with octanedioic acid

Supports adhesion, expansion and maintenance of the CE phenotype; tested on the HCEC-12 cell line and porcine CECs

[125]

Poly (D, L‐lactic acid) and cross-linkable gelatins

Supports proliferation and correct phenotype of cultured CECs; tested on primary human CECs and the B4G12 cell line

[126]

Poly (glycerol sebacate) with poly (ε-caprolactone)

Supports the formation of confluent CE monolayers and the maintenance of the CE phenotype; tested on HCEC-12 cell line and human conjunctival epithelial cells. This biodegradable scaffold is semi-transparent, non-immunogenic and highly elastic

[127]