Innovative Methodology Rat liver endothelial cells isolated by anti-CD31 immunomagnetic separation lack fenestrae and sieve plates

DeLeve, Laurie D., Xiangdong Wang, Margaret K. McCuskey, and Robert S. McCuskey. Rat liver endothelial cells isolated by anti-CD31 immunomagnetic separation lack fenestrae and sieve plates. Am J Physiol Gastrointest Liver Physiol 291: G1187–G1189, 2006. First published June 15, 2006; doi:10.1152/ajpgi.00229.2006.— The gold standard for the identification of sinusoidal endothelial cells (SEC) is the presence of fenestrae organized in sieve plates, which is characteristic of SEC in vivo. One of the methods currently in use to isolate SEC is immunomagnetic sorting for CD31. However, there is evidence to suggest that CD31 is not present on the surface of differentiated SEC. The present study used scanning electron microscopy to image rat hepatic endothelial cells isolated by anti-CD31 and immunomagnetic sorting and cells isolated by gradient centrifugation and centrifugal elutriation. Cells isolated by elutriation had welldeveloped fenestrae and sieve plates, whereas cells isolated by antiCD31 and immunomagnetic sorting had significantly fewer fenestrae organized in sieve plates. In conclusion, cells isolated by anti-CD31 and immunomagnetic sorting lacked the hallmark features of SEC.