FOR IMMEDIATE RELEASE
Report in PNAS on role of Nephrin, the kidney
Research Triangle Park, N.C., July 6 /PRNewswire/ -- BioStratum Incorporated announced today the publication in the journal "Proceedings of the National Academy of Sciences" (volume 96, pages 7962-7967) of the paper entitled "Nephrin is specifically located at the slit diaphragm of glomerular podocytes." The work was completed in the laboratory of one of BioStratum's founding scientists, Dr. Karl Tryggvason of the Karolinska Institute, Stockholm, Sweden.
In this paper, nephrin is found at the "slit diaphragm," also referred to as the "slit membrane," an important structure in the kidney's filtration barrier. Until now, very little has been known about how the kidney filters blood. Nephrin appears to form a "zipper-like" filtration structure that functions both as a key structural motif which organizes and maintains the integrity of the filtration barrier as well as a porous filtration structure that allows the liquid portion of the blood to pass but not plasma proteins.
A break-down in the kidney's ability to filter proteins is a common occurrence
in most kidney diseases, and results in proteinurea (protein in the urine).
Proteinuria is not only
"This advance holds great promise for the development
The present work elegantly depicts the location of nephrin at the slit membrane using nephrin specific antibodies that can be detected by electron microscopes. The structural domains of the nephrin molecule suggest a membrane bound receptor that self-associates with a nephrin molecule on a neighboring podocyte cell surface, thus forming a zipper-like connection between the cells, i.e. the slit membrane.
The nephrin gene was originally identified using genetic linkage analysis on patients with a rare disease called congenital nephrotic syndrome, which is a disease characterized by massive proteinuria. The discovery of the nephrin gene was reported last year by Dr. Tryggvason's group in a paper published in Molecular Cell (March 1998, Volume 1, pages 575-582).
"The absence of a functioning nephrin protein has a profound effect on
the kidney's filtration barrier.
BioStratum is pursuing several approaches to increase nephrin production
including the identification of small molecule drugs that specifically
increase nephrin expression, and the application of BioStratum's
BioStratum Incorporated is a privately held company developing proprietary therapeutics based on recent scientific advances in basal lamina and related technologies. The company's therapeutics are directed against novel basal lamina extracellular targets involved in degenerative and invasive disease processes fundamental to kidney disease, diabetes and cancer. The company has also developed methods for the production of recombinant basal lamina proteins for use in wound repair and advanced tissue regeneration protocols.