Effect of peripheral blood mononuclear cells from patients with nephrotic syndrome on uptake of 35sulfate by glomerular basement membrane.

We have studied the effect of peripheral blood mononuclear cells (PBMC) from nephrotic patients on the incorporation of 35Sulfate in rat glomerular basement membrane. 35Sulfate uptake increased when glomeruli were incubated with PBMC from 10 patients with idiopathic minimal lesion nephrotic syndrome (IMLNS) in relapse compared to simultaneous assays on 5 controls (2295 +/- 643 cpm/mg dry glomerular weight, mean +/- SEM, and 962 +/- 248 cpm/mg, respectively) (P less than 0.02). 35Sulfate incorporation did not increase when glomeruli were incubated with PBMC from seven nephrotic patients with other glomerulopathies (1283 +/- 642 cpm/mg) as compared to controls (1016 +/- 503 cpm/mg). No significant differences in 35Sulfate uptake were seen between glomerular cultures with and without control PBMC. These data show that PBMC from patients with IMLNS in relapse alter, at least in the rat GBM, the metabolism of sulfated compounds. Since these compounds have a role in glomerular permeability, this finding may have pathogenic significance.