Permeability, ultrastructural changes, and distribution of novel proteins in the glomerular barrier in early puromycin aminonucleoside nephrosis.

Background/aims: It is still unclear what happens in the glomerulus when proteinuria starts. Using puromycin aminonucleoside nephrosis (PAN) rats, we studied early ultrastructural and permeability changes in relation to the expression of the podocyte-associated molecules nephrin, α-actinin, dendrin, and plekhh2, the last two of which were only recently discovered in podocytes.

Methods: Using immune stainings, semiquantitative measurement was performed under the electron microscope.

Dendrin expression in glomerulogenesis and in human minimal change nephrotic syndrome.

Background: Dendrin is an 81-kD cytosolic protein hitherto described in the brain, where it is associated with the actin cytoskeleton. Recently, we found dendrin in foot processes of mouse glomerular podocytes. Here we describe its expression both during mouse glomerulogenesis and in the normal and diseased human kidney for the first time.

Circulating inflammatory endothelial cells contribute to endothelial progenitor cell dysfunction in patients with vasculitis and kidney involvement.

Impaired angiogenic function has been reported in patients with kidney failure. During vascular damage, endothelial cells may detach from the site of inflammation and be released into the peripheral blood. With the use of Wegener's granulomatosis as a study model, whether circulating inflammatory endothelial cells (IEC) can (1) be used as a disease activity marker and (2) contribute to sustained vascular damage by inducing endothelial progenitor cell (EPC) dysfunction were examined.

Wegener's granulomatosis is associated with organ-specific antiendothelial cell antibodies.

Background: Antiendothelial cell antibodies (AECA), usually detected using human umbilical vein endothelial cells (HUVEC), are frequently observed in systemic vasculitis, but their pathogenic role is unclear. Heterogeneity of endothelial cells necessitates use of clinically relevant endothelial cells for elucidation of the role of AECA in systemic vasculitis involving small blood vessels of specific organs.

Methods: Human endothelial cells were isolated from normal tissue specimens from the nose, kidney, lung, liver, and umbilical vein.

A randomized trial of maintenance therapy for vasculitis associated with antineutrophil cytoplasmic autoantibodies.

Background: The primary systemic vasculitides usually associated with autoantibodies to neutrophil cytoplasmic antigens include Wegener's granulomatosis and microscopic polyangiitis. We investigated whether exposure to cyclophosphamide in patients with generalized vasculitis could be reduced by substitution of azathioprine at remission.

Methods: We studied patients with a new diagnosis of generalized vasculitis and a serum creatinine concentration of 5.

Altered ultrastructural distribution of nephrin in minimal change nephrotic syndrome.

Background: Nephrin is a cell-adhesion protein that is defective in congenital nephrotic syndrome of the Finnish type (CNF). Nephrin is synthesized by the podocytes and is localized to the slit membrane between individual foot processes of the podocytes. Although nephrin is apparently pivotal in the development of CNF, the role of nephrin in other causes of nephrotic syndrome is not fully understood.

Serum sFAS levels are elevated in ANCA-positive vasculitis compared with other autoimmune diseases.

The role of the Fas/FasL system in ANCA-associated vasculitis is unclear. We therefore assessed levels of soluble Fas (sFas) in sera and Fas expression on mononuclear cells from patients with ANCA-positive vasculitis and compared the results with those found in other rheumatic diseases. Serum levels of sFas were determined by ELISA.