GLOMERULAR VASCULAR CELL-ADHESION MOLECULE-1 EXPRESSION IN RENAL VASCULITIS

Aims-To study the expression of cell adhesion molecules in the renal b iopsy specimens of patients with systemic vasculitis and Henoch-Schonl ein purpura (HSP); to correlate this with the severity of glomerular i nflammation. Methods-Renal biopsy specimens obtained from eight patien ts with untreated systemic vasculitis (four with Wegener's granulomato sis and four with microscopic polyarteritis), eight with HSP and nine controls (four with normal histopathology and five with thin glomerula r basement membrane disease) were stained using the alkaline phosphata se anti-alkaline phosphatase method with monoclonal antibodies directe d against intercellular adhesion molecule-1 (ICAM-1), vascular cell ad hesion molecule-1 (VCAM-1) and E-selectin. Results-Biopsy specimens of normal kidneys expressed ICAM-1 in glomerular endocapillary cells, Bo wman's capsule epithelium, interstitial cells and interstitial vascula r endothelium, and VCAM-1 in Bowman's capsule epithelium, proximal tub ular epithelium and interstitial vascular endothelium. No staining wit h antibody directed against E-selectin was seen in any of the biopsy s pecimens. Biopsy specimens of patients with a vasculitic glomeruloneph ritis (segmental necrotising glomerulonephritis) expressed VCAM-1 in g lomerular endocapillary cells (four of eight patients with systemic va sculitis; two of eight patients with HSP). In patients with a systemic vasculitis glomerular VCAM-1 expression was associated with a more se vere renal lesion (44, 50, 60, and 65% of glomeruli involved) than in those not showing glomerular VCAM-1 expression (3, 3, 11, and 39% of g lomeruli involved). Conclusion-Expression of VCAM-1 by glomerular endo capillary cells in renal biopsy specimens raises the possibility that recruitment of VLA-4 bearing leucocytes may contribute to glomerular i njury in Wegener's granulomatosis and microscopic polyarteritis.