Genotypic variation in the human interleukin-10 (IL-10) promoter may account for marked inter-individual variation in IL-10 production and may influence susceptibility to autoimmune diseases. The G/A polymorphism at position -1082 has been linked to high/low IL-10 producer status. We directly tested the functional significance of this polymorphism using DNA-binding assays and reporter gene assays, examined allele frequencies in two geographically distinct populations and assessed intra- and inter-individual variation in IL-10 production in vitro according to genotype. Functional analyses showed that the -1082 region contains a putative ETS-like transcription factor-binding site, and nuclear factors from a monocyte cell line bind to this region. Transient transfection studies in an Epstein-Barr virus-transformed B cell line indicated that the -1082 A allele confers a two fold increase in transcriptional activity of the IL-10 promoter compared to the G allele. There was marked inter-individual variation in IL-10 production by peripheral blood mononuclear cells in vitro, with no consistent effect of genotype.

SUMMARYImmune responses can be classi®ed, according to the predominant cytokines involved, into type 1 (featuring interferon-c, IFN-c) and type 2 (featuring interleukin-4, IL-4); imbalance between type 1 and type 2 cytokine compartments has been implicated in many human diseases. Levamisole is a drug with an unknown mode of action that has been used to boost immunity in infectious diseases including leprosy, and in some cancers. To test the hypothesis that levamisole acts by inducing a shift to a type 1 immune response, we used Brown Norway (BN) rats, which are markedly biased to type 2 responses. BN rats treated with levamisole showed a dose-dependent rise in serum IFN-c and fall in serum immunoglobulin E (IgE) level. Detailed analysis of cytokine gene expression showed upregulation of IFN-c and downregulation of IL-4 messenger RNA. This coincided with marked upregulation of IL-18, a recently characterized cytokine with potent activity in stimulating IFN-c production. IL-12 was not induced. Further, the type 2 response induced in BN rats by mercuric chloride was markedly attenuated when rats were pretreated with levamisole: there was a 2-log reduction in maximum serum IgE level and marked attenuation of IL-4 gene upregulation. These data indicate that levamisole acts by resetting the immune balance towards a type 1 response via induction of IL-18. Our ®ndings provide a direction for development of more speci®c immunomodulating therapy.

Patients with primary FSGS and nephrotic range proteinuria, who are treated with corticosteroids, are more likely to enter remission than those who are not treated. Remission rates of up to 80% can be achieved with prolonged treatment, and remission is an independent predictor of survival off dialysis. Patients who do not achieve remission have a poor prognosis. Further clarification of optimal treatment regimens requires additional, prospective studies.

glycans (PGs) are important for the glomerular barrier, for cell signaling, and for the anchorage of cells to the glomerular basement membrane. They are, however, complex macromolecules, and their production has not yet been thoroughly investigated in podocytes. In the present study, we studied the biosynthesis of PGs by highly differentiated human podocytes and in rats. The cells were treated with puromycin aminonucleoside (PAN; a nephrosis-inducing agent), steroids (used as primary treatment for nephrotic syndrome), or both. Analysis was made by TaqMan real-time PCR, Western blotting, and by metabolic labeling with 35 S and 3 H. We found that podocytes produce versican, syndecan-1, decorin, and biglycan together with the previously known PG syndecan-4, glypican, and perlecan. PAN treatment downregulated the mRNA and the protein expression of both versican (by 24 Ϯ 6%, P Ͻ 0.01, for mRNA and by 50% for protein) and perlecan (by 14 Ϯ 5%, P Ͻ 0.05, for mRNA and by 50% for protein). The decreased expression was confirmed by studying the glomerular gene expression in rats treated with PAN during a time course study. In addition, puromycin decreased the expression of enzymes involved in the glycosaminoglycan biosynthesis. Steroid treatment decreased perlecan (by 24 Ϯ 3%, P Ͻ 0.01) and syndecan-1 expression (by 30 Ϯ 4%, P Ͻ 0.01) but increased the expression of decorin 2.5-fold. The observed alterations of PG synthesis induced by PAN may lead to decreased glomerular anionic charge and disturbed podocyte morphology, factors that are important for the development of a nephrotic syndrome. glomerular barrier; puromycin; glycosaminoglycan biosynthesis A GROWING AMOUNT OF EVIDENCE supports the idea of the glomerular filtration barrier as an integrative structure (7,15). It is known that the barrier is selective to solutes passing through it depending on their shape, size, and charge (7,30). Most of the size-selective properties have lately been ascribed to the podocytes and their slit diaphragm, where several novel proteins have been found during the last decade (14, 38, 41), whereas the site for charge selectivity seems to be situated in several levels of the barrier (7, 15). The glomerular basement membrane is the structure that has been ascribed the most chargeselective properties (21, 41), but it has recently been questioned (4). We and others previously showed that the glomerular endothelial glycocalyx consists of negatively charged components such as proteoglycans (PGs) (3,20,34,39) and that it has charge-selective properties (20,40,42). Another possible site for charge interaction is the podocyte and there are previous reports concerning the podocyte cell surface and the involvement of negatively charged molecules such as podocalyxin (23) and the PG agrin (32). PGs are built up by a core protein with one or more polyanionic galactose or glucosaminoglycan (GAG) chains. The GAG chains are involved in cell signaling through the binding and storing of several different growth factors (such as TGF and FGF), cytokines, an...