Open Access

Paul Gutwein, Anja Schramme, Mohamed Sadek Abdel-Bakky, Kai Doberstein, Ingeborg A. Hauser, Andreas Ludwig, Peter Altevogt, Stefan Gauer, Anja Hillmann, Thomas Weide, Christine Jespersen, Wolfgang Eberhardt, Josef Pfeilschifter

• Background: The importance of the Notch signaling in the development of glomerular diseases has been recently described. Therefore we analyzed in podocytes the expression and activity of ADAM10, one important component of the Notch signaling complex. Methods: By Western blot, immunofluorescence and immunohistochemistry analysis we characterized the expression of ADAM10 in human podocytes, human urine and human renal tissue. Results: We present evidence, that differentiated human podocytes possessed increased amounts of mature ADAM10 and released elevated levels of L1 adhesion molecule, one well known substrate of ADAM10. By using specific siRNA and metalloproteinase inhibitors we demonstrate that ADAM10 is involved in the cleavage of L1 in human podocytes. Injury of podocytes enhanced the ADAM10 mediated cleavage of L1. In addition, we detected ADAM10 in urinary podocytes from patients with kidney diseases and in tissue sections of normal human kidney. Finally, we found elevated levels of ADAM10 in urinary vesicles of patients with glomerular kidney diseases. Conclusions: The activity of ADAM10 in human podocytes may play an important role in the development of glomerular kidney diseases.