EXPRESSION OF MEMBRANE GLYCOCONJUGATES ON SHEEP LUNG ENDOTHELIUM

BACKGROUND: Carbohydrates play an important role in both the regulatio n and expression of endothelial cell surface molecules. EXPERIMENTAL D ESIGN: To investigate the molecular phenotype of endothelial cells in the sheep lung, we used a panel of 39 lectins and carefully titrated l ectin histochemistry to identify small vessel glycoconjugates. Express ion of glycoconjugates on isolated cells was studied by flow cytometry and lectin Western blotting. RESULTS: Eight lectins stained small ves sel endothelium with minimal background staining. To confirm cell surf ace binding, endothelial cells from the peripheral lung were isolated and tested for lectin recognition by flow cytometry. Three lectins (Da tura stramonium, Griffonia simplicifolia-l, Lycopersicon esculentum) a lso stained isolated lung cells by flow cytometry. A lectin Western tr ansfer technique demonstrated common binding to a high molecular weigh t (100 to 130 kD) band. CONCLUSIONS: The use of lectins as probes of c ell surface carbohydrate expression supports the possibility of select ive glycoconjugate expression on sheep endothelium.