Renin Immunohistochemistry and Nephropathology
Family A, patients DIV3, DIV7, and DII1.
(A–C) Renin expression in control kidney.
(A) Control aged 7 years; renin expression in JG cells and individual cells of collecting ducts.
(B and C) Adult control; renin staining (B) in JG cells and (C) in renal cortical tubules where the signal is restricted to individual cells of the collecting ducts.
(D and E) Kidney biopsies in an early disease stage. Patient DIV3 (D) and patient DIV7 (E) shown. The common denominator is a strong reduction of renin signal in the JG apparatus (marked by arrows) and its absence in the surrounding tubules. Insert in (E) shows glomerulus in detail.
(F) Patient in advanced stage of kidney disease (DII1). Renin staining is absent in both JG apparatus and tubular epithelium even in relatively well-preserved regions.
(G–I) Renin and prorenin expression inside the wall of small size renal vessels, probably in a sub/endothelial localization, more prominent in adult patient DII1 (the main pictures) than in patients in an early stage of the disease (inserts). Preprorenin antibody detecting prorenin and renin (G), monoclonal antibody detecting active renin (H), and polyclonal antibody detecting prorenin (I). Insert in (G) demonstrates this phenomenon in patient DIV7, inserts in (H) and (I) in patient DIV3.
(J–L) Nephropathology in early stage of the disease (HE staining).
(J) Morphology in patient DIV3 was dominated by irregular dystrophic changes in tubular epithelium mainly in proximal tubules (coarsely vacuolated or granular cytoplasm) and focal segmental sclerosis of glomerular tufts with adhesions to Bowman's capsule. Tubular atrophy and interstitial fibrosis was less expressed (sampling?).
(K and L) Kidney biopsy from patient DIV7 demonstrated more pronounced glomerular sclerosis and hyalinosis (1 out of 8 glomeruli was totally sclerosed, not shown) and focal tubular atrophy accompanied with moderate interstitial fibrosis. Glomeruli, marked as Gs, in various degrees of sclerosis and areas of tubulointerstitial fibrosis are shown. In advanced stage of the disease (patient DII1, not shown), morphology of progressive nephropathy was modified by haemodialysis lasting for 1 year.