Demonstration of anti-laminin antibodies in the serum of healthy subjects

Antibodies directed against laminin, a glycoprotein of basement membranes, have been sought for in the sera of 347 healthy subjects by a method relying on the agglutination of laminin-coated latex particles. Fifty-five subjects (15.9%) hae been found to be positive, 37 with a titre of 2, 14 with a titre of 4 and 4 with a titer of 8. Applied to 106 patients whose a renal biopsy had been examined by immunofluorescence, the test yielded positive results in 91% of patients with linear deposits as compared to 10.3 and 15.4% respectively in patients presenting with and without granular deposits along the glomerular basement membrane. The titers in anti-laminin antibodies observed in these patients ranged from 2 to 8. The discovery of circulating anti-laminin antibodies in serum from subjects without clinical or subclinical sign of renal impairment rises several questions regarding the pathogenicity of these auto-antibodies and their possible association with genetic or environmental factors.