Urinary Immunoglobulin Components in Normal, Tubular, and Glomerular Proteinuria: Quantities and Characteristics of Free Light Chains, IgG, IgA, and Fcγ Fragment.

The urinary excretion of free light immunoglobulin chains IgG, IgA, and Fcγ fragment material has been estimated in 12 healthy individuals and 7 subjects with tubular or glomerular proteinuria. Measurements were carried out by immunochemical methods after separation of concentrated urinary immunoglobulin components by gel chromatography. Various components were isolated and their sedimentation constants, Stokes' radii, diffusion coefficients, molecular weights, and frictional ratios were determined.