A 3D Polymer Scaffold Platform for Enhanced in vitro Culture of Human & Rabbit Buccal Epithelial Cells for Cell Therapies

BACKGROUND

Buccal mucosal epithelial cells show promising application for various regenerative medicine approaches. In this study, we examined the feasibility of culturing rabbit and human buccal mucosal epithelial cells in a novel thermoreversible gelation polymer (TGP) scaffold, without feeder layers or other foreign proteins.

METHODS & RESULTS

The results of this 28-day in vitro culture, u sing the conventional technique (2D) and TGP (3D) showed that the epithelial cell morphology could be maintained only in the TGP group while cells in the 2D group de-differentiated to fibroblast morphology in both human and rabbit samples. CK3 expression, a marker for epithelial differentiation was higher in 3D-TGP cultured cells than 2D.

CONCLUSION

TGP based in vitro cell culture is a prospective methodology to culture buccal mucosal epithelial cells efficiently without using foreign biological components for tissue engineering applications.

Coexistence of Meesmann Corneal Dystrophy and a Pseudo-Unilateral Lattice Corneal Dystrophy in a Patient With a Novel Pathogenic Variant in the Keratin K3 Gene: A Case Report

PURPOSE

This study aims to clinically and genetically report a case of coexisting Meesmann corneal dystrophy (MECD) and pseudo-unilateral lattice corneal dystrophy (LCD).

METHODS

Clinical characterization was supported by a complete ophthalmological evaluation, including visual acuity measurement and slit-lamp examination. Molecular diagnosis was performed by whole-exome sequencing analyzing the gelsolin, keratin K3 (KRT3), keratin K12, and transforming growth factor-beta-induced genes.

RESULTS

A 57-year-old woman presented with recurrent corneal erosions over 17 years and visual impairment in both eyes. Ophthalmological evaluation revealed multiple central tiny cysts in the epithelium of both eyes and lattice linear lesions only in the right cornea. In both eyes, a corneal posterior crocodile shagreen degeneration could also be observed. These findings were compatible with a MECD and a unilateral LCD. Molecular analysis identified the novel heterozygous nucleotide substitution c.1492G>A (amino acid change p.Glu498Lys) in the KRT3 gene, in cosegregation with the MECD familial phenotype. However, no genetic evidence supported the unique LCD phenotype observed in the patient.

CONCLUSIONS

To the best of our knowledge, this is the first report of a pseudo-unilateral LCD in a patient with coexistent MECD. Moreover, the genetic analysis showed a novel mutation in the previously MECD-associated gene KRT3.

Reconstruction of rabbit corneal epithelium on lyophilized amniotic membrane using the tilting dynamic culture method

Rabbit corneal epithelium was reconstructed using tilting dynamic culture with a self-manufactured, amniotic membrane (AM) supporter and a lyophilized amniotic membrane (LAM). Rabbit corneal epithelial (RCE) cells were cultured and cryopreserved after isolation from the limbus. The second- and third-passage RCE cells were plated onto the epithelial side of the LAM of Ahn's AM supporter. Two days later, the air-liquid interface culture was maintained with third-passage RCE cells for 6 days and second-passage corneal epithelial cells for 9 days. The average viability of thawed RCE cells, assessed using trypan blue dye exclusion, was 77.42%. The reconstructed corneal epithelium was characterized by histological (hematoxylin and eosin) and immunohistochemical staining (proliferating cell nuclear antigen) for light microscopy, and by reverse transcriptase-polymerase chain reaction, glucose assay, and transmission electron microscopy. The basal layer of the reconstructed corneal epithelium was well formed, and the epithelium was tightly constructed due to the increase in cell proliferation and differentiation caused by the tilting dynamic culture, as opposed to static culture. Tilting dynamic culture was useful for the reconstruction of the epithelium using easily damaged epithelial cells and resulted in more stratum cell layers. Moreover, cytokeratin (CK3) mRNA expression in tilting dynamic cultured third-passage RCE cells seeded onto AM was greater than in static cultured third-passage RCE cells. The morphology of the reconstructed corneal epithelium on LAM by tilting dynamic culture for 9 days resembled that of the skin epidermis. This was thought to be because the tilting dynamic culture not only accelerated the proliferation and differentiation of cells by physical or mechanical stimulation, but also ensured that the supply of medium was delivered to the basal cells more efficiently. Thus, the reconstruction of the corneal epithelium using LAM and tilting dynamic culture was considered to be a good in vitro model for autologous or allogeneic transplantation of corneal epithelium and skin epidermis in patients with damaged epithelia.