Cultured lung epithelium: A cellular model for lung preservation.

Cellular models have helped with the development of conditions needed for hypothermic preservation of kidney, liver, and heart. Recently, highly differentiated cultured lung epithelial cell lines grown with basolateral side feeding technique have become available that can mimic airspace, epithelium, and interstitium of lung parenchyma. Cultured lung epithelium coupled with Ussing's short-circuit current technique was used as a cellular model system for lung preservation. A parametric study was conducted to correlate the effects of luminal fluid composition (University of Wisconsin (UW) solution and phosphate-buffered saline) and storage gas (air vs nitrogen) at 4 degrees C for 24 h on postischemic electrogenic properties (transepithelial ion transport and resistance). The results showed that cells were better preserved with the UW solution on both sides as measured by their transepithelial resistance, an indicator of tight junction integrity (Rte approximately 65% of control values approximately 135 Omega cm2). In addition, they responded better to mediators that stimulate chloride secretion than cells preserved with other conditions. Cells preserved with no additional fluid on the apical side had substantially lowered Rte (<20%) than those preserved with an additional thin layer of fluid ( approximately 35-65%). This cellular model system is a realistic representation of lung epithelium and can provide an accurate assessment of preservation quality through the measurements of tight junction integrity and active ion transport. Copyright 1997 Academic Press.