Enhanced suppressor T cell activity resulting in increased IgM and decreased IgG productions in children with minimal change nephrotic syndrome.

In order to clarify the cellular basis accounting for the decreased serum IgG and increased serum IgM in children with minimal change nephrotic syndrome (MCNS), peripheral blood mononulcear cells (MNC) were obtained from 15 children with biopsy-proved MCNS and 15 age- and sex-matched normals. MNC were then separated into helper (OKT4) T cells, suppressor (OKT8) T cells, B cells and monocytes. Different cell populations from patients and normals were then recombined and pokeweed mitogen-stimulated in vitro immunoglobulin biosynthesis was studied. The results strongly suggest the presence of isotype-specific suppressor T cells which may affect the switch of IgM B cells to IgG B cells in patients with MCNS and may be used to explain partly the clinical findings of lowered serum IgG and increased IgM in those individuals.