HCEnC-21 and HCEnC-21T retain typical corneal endothelial barrier integrity and pump function.

<p>(A) Cells were plated in 12-well transwell inserts (0.4 µm) at a density of 100,000 cells per transwell and transendothelial resistance (TER) was measured every 2 or 4 days over the course of 4.5 wk. Note that earlier (32–39) and later (58–67) passages of both HCEnC-21 and HCEnC-21T established a typical corneal endothelial barrier of 15 Ω*cm² after about 2 wk and maintained this barrier for 2.5 more wk. (B,C) HCEnC-21 (B) and HCEnC-21T (C) were grown to confluence (3,000 cells/cm²) in perfusion chambers and 20 mM lactate was applied to their apical, basolateral or both cell membranes. Facilitated lactate uptake is H⁺ coupled and was measured indirectly by detecting intracellular pH changes using the BCECF-AM fluorescent dye. Temporal acidification of both HCEnC-21 and HCEnC-21T was observed after lactate pulses to the apical and basolateral membrane. Error bars indicate mean ± SEM. *, P<0.05.