Advances in the biology and genetics of the podocytopathies: implications for diagnosis and therapy.
BACKGROUND
Etiologic factors and pathways leading to altered podocyte phenotype are clearly numerous and involve the activity of different cellular function.


OBJECTIVE
To focus on recent discoveries in podocyte biology and genetics and their relevance to these human glomerular diseases, named podocytopathies.


METHODS
Genetic mutations in genes encoding for proteins in the nucleus, slit diaphragm, podocyte cytoplasm, and cell membrane are responsible for podocyte phenotype and functional abnormalities. Podocyte injury may also derive from secondary stimuli, such as mechanical stress, infections, or use of certain medications. Podocytes can respond to injury in a limited number of ways, which include (1) effacement, (2) apoptosis, (3) arrest of development, and (4) dedifferentiation. Each of these pathways results in a specific glomerular morphology: minimal change nephropathy, focal segmental glomerulosclerosis, diffuse mesangial sclerosis, and collapsing glomerulopathy.


CONCLUSIONS
Based on current knowledge of podocyte biology, we organized etiologic factors and morphologic features in a taxonomy of podocytopathies, which provides a novel approach to the classification of these diseases. Current and experimental therapeutic approaches are also discussed.
Barisoni
Laura
L
Department of Pathology and Medicine, Division of Nephrology, New York University School of Medicine, New York, NY 10017, USA. barisol01@med.nyu.edu
Schnaper
H William
HW
Kopp
Jeffrey B
JB
D017209:Apoptosis / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D009154:Mutation / Q000235:genetics; D050199:Podocytes / Q000187:drug effects / Q000473:pathology*