Cultured Human Corneal Endothelial Cell Aneuploidy Dependence on the Presence of Heterogeneous Subpopulations With Distinct Differentiation Phenotypes

PURPOSE: Cultured human corneal endothelial cells (cHCECs) are anticipated to become an alternative to donor corneas for the treatment of corneal endothelial dysfunction. However, cHCECs reportedly tend to exhibit chromosomal abnormality during in vitro cell division, thereby hampering their use in the clinical setting. The purpose of this study was to clarify whether a specified subpopulation (SP) of heterogeneous cHCECs would exhibit aneuploidy, whereas other SPs would not. METHODS: The presence of SPs in cHCECs was analyzed on the basis of surface cluster of differentiation (CD) antigen CD166, CD105, CD44, CD26, and CD24 expression levels by flow cytometry. Cytogenetic examination was performed for 23 lots of cHCECs, either as whole-cell preparations (bulk) consisting of mixed SPs or as a semipurified SP by magnetic activated cell sorting (MACS). The HCEC donors ranged from 9 to 69 years of age and the culture passages from primary to fifth passage. RESULTS: Flow cytometry analysis demonstrated the presence of at least three cHCEC SPs. One SP, purified by MACS, with surface expression of CD166+, CD105-, CD44-, CD24-, and CD26- did not show any aneuploidy in 50 cells. However, CD166+, CD44+++, CD24-, and CD26+ cHCEC SPs showed sex chromosome loss in all cells (60 cells), whereas CD166+, CD44+++, CD24+, and CD26- SPs exhibited, albeit partly, trisomy on chromosomes 6, 7, 12, and 20. CONCLUSIONS: We found that cHCEC aneuploidy is linked to specified SPs present in cHCECs and that the SP sharing the surface phenotype with mature HCECs in corneal tissues was devoid of the karyotype abnormality.