Globotriaosylceramide expression in human placental fetal capillaries

Konference: 2010 6. sympózium a workshop molekulární patologie a histo-cyto-chemie

Kategorie: Onkologická diagnostika

Téma: Postery

Číslo abstraktu: p005

Autoři: MUDr. Helena Hůlková, Ph.D.; Prof. MUDr. Milan Elleder (1938 - 2011), DrSc.; F. Šmíd; J. Ledvinová; L. Kuchař

Introduction: Globotriaosylceramide (Gn3Cer) is the main stored lipid in Fabry disease (deficiency of alpha galactosidase). There is dearth of knowledge on its distribution in normal tissues.

Aim: We had access to placentas examined for prenatal diagnosis of Fabry disease. Having effective commercially available antibody against Gb3Cer we extended the standard examination of placentas with this disorder beyond the usual electronmicroscopy (used for detection of lysosomal lipid storage) and we were surprised by the presence of Gb3Cer in the capillary endothelium unrelated to storage. This led us to examine healthy control placentas.

Material and Methods: A series of placentas at term were examined using imunohistochemical in situ analysis of Gb3Cer, lactosylceramide, and GM1 ganglioside (with cholera toxin-B subunit). The results of in situ analyses were correlated with extra situ biochemical analysis and with tandem mass spectrometry.

Results: Immunohistochemical study of a series of placentas at term showed uniform distinct staining of the apical membrane of the capillary endothelial cells for globotriaosylceramide (Gb3Cer) using monoclonal antibody. The lipid was not detectable in endothelial cells of arterial and umbilical veins and in capillaries in somatic structures (heart, skin, skeletal muscle) of neonates available. Gb3Cer was also detected in heparinocytes and in stromal cells of placental villi. Both cyto- and synciciotrophoblast, smooth muscle cells and mesothelial cells were negative. In situ correlation of Gb3Cer with other glycosphingolipids showed coexistence with GM1 ganglioside only in endothelial cels of placental capillaries. Lactosylceramide was restricted to Hoffbauer cells.

Conclusion: The findings point to specific glycolipid microdomains of endothelial cells of placental fetal capillaries which may reflect specific regulation.

Datum přednesení příspěvku: 23. 4. 2010