Monoclonal antibody analysis of glomerular and renal interstitial immune cells in steroid-resistant and steroid-responsive minimal change disease in children.

Glomerular and interstitial leukocyte infiltrates were studied by indirect immunoperoxidaze technique using monoclonal antibodies against all leukocytes, pan-T lymphocytes, helper/inducer CD4 cells, suppressor/cytotoxic CD8 cells, pan-B lymphocytes, monocytes/macrophages and polymorphs in 23 renal biopsy samples obtained from children with minimal change disease (MCD). The cases were classified on the basis of light, electron microscopy and immunofluorescence. Nephrotic syndrome was steroid-sensitive in 15 patients (group I) and steroid-resistant in 8 subjects (group II). Both groups did not differ in the type or number of glomerular immune cells, quantified as immunopositive cells per glomerular cross section. Intraglomerular cellular infiltrates were mainly constituted of monocytes/macrophages; among T lymphocytes T helper/inducer cells predominated over T cytotoxic/suppressor cells. Enumeration of interstitial immune cells showed significantly higher number of all leukocytes and T lymphocytes, quantified as immunopositive cells/mm2, in steroid-resistant group. T helper/inducer cells predominated over T cytotoxic/suppressor cells in the renal interstitium in steroid-responsive and in steroid-resistant MCD. The leukocyte infiltrates did not correlate with a degree of proteinuria at the tine of biopsy and with the renal cortical interstitial volume in both studied groups. Our data suggest, that steroid resistance in minimal change nephropathy in children seems to be related to interstitial T lymphocytes.