Atsushi Fukatsu

Elevation of interleukin-6 in inflammatory bowel disease is macrophage- and epithelial cell-dependent

Local interleukin-6 (IL-6) activity was studied using colonic mucosal tissues in inflammatory bowel disease (IBD) and inflammatory control patients. Active IBD specimens exhibited significantly higher IL-6 activity than control specimens in both cultures of isolated lamina propria mononuclear cells (LPMC) and mucosal tissues with an increased number of IL-6-producing cells. However, the activity in inactive IBD or inflammatory controls did not differ from controls. Northern blot analysis demonstrated IL-6 messenger RNA in LPMC and colonic epithelial cells isolated from active IBD specimens but not in control cells. Furthermore, immunofluorescent microscopic study of active IBD specimens showed more conspicuous staining of IL-6 in infiltrating LPMC (mostly CD68+ cells) and colonic epithelial cells. These results suggest that elevation of local IL-6 activity may be a characteristic feature of active IBD and both macrophages and colonic epithelial cells are the major cell types responsible for this phenomenon.

A Case of Nephrotic Syndrome with Glomerular Lipoprotein Deposition with Capillary Ballooning and Mesangiolysis

A 33-year-old man with nephrotic syndrome and rapid deterioration of renal function showed curious glomerular morphological abnormalities. Ballooning of the glomerular capillaries due to a substance accumulated in the capillary lumina and mesangiolysis were prominent histological features. The deposits in the capillary lumen were positive for Sudan III staining, and also for beta-lipoprotein, apoprotein B and apoprotein E by immunofluorescent technique. The staining of beta-lipoprotein in a flower leaf pattern was a striking characteristic, while such staining was negative when studied in 20 patients with nephrotic syndrome who were used as controls. Based on these findings, the morphological abnormalities in this case were considered to be related to lipoprotein deposition in the glomeruli. This case is thought to be the first reported in a complete form in the literature which could be classified as a new kind of disease related to lipoprotein metabolism abnormalities.

Localization of 20-kD homologous restriction factor (HRF20) in diseased human glomeruli. An immunofluorescence study.

The 20‐kD homologous restriction factor (HRF20), which is identical to CD59, is a membrane‐associated protein which inhibits the reaction of C9 to form membrane attack complex (MAC) of homologous complements. In various human glomerular diseases deposition of complement components is frequently seen and MAC is reported to associate with immune deposits. Using a specific monoclonal antibody, 1F5, against HRF20, we attempted to study the localization of HRF20 in human glomerulonephritides and to compare the localization of HRF20 with those of immune deposits and MAC. The frozen sections of kidney specimens were fixed in acetone at room temperature before staining. In normal kidneys and kidney specimens from the patients with minimal change nephrotic syndrome, membranous nephropathy. and IgA nephropathy. HRF20 was strongly localized in the peritubular capillaries and along Bowmans capsules. A weaker but well‐defined staining was obtained in the mesangial area and faint staining was seen along the glomerular capillary walls. In contrast, glomerular capillary walls were rather strongly stained in the cases with diffuse lupus nephritis which had subendothelial dense deposits. These data suggest that HRF20 (CD59) is present in the human glomeruli and its expression is enhanced under certain conditions such as lupus nephritis.

Mucosal Chemokine Activity in helicobacter pylori Infection

We examined secretion, mRNA expression, and histologic localization of interleukin-8 (IL-*) and growth-related gene product-alpha (GRO alpha) in the Helicobacter pylori-infected gastric antral mucosa. Antral biopsies were obtained from an area of endoscopically intact mucosa. Significantly higher levels of IL-8 and GRO alpha were secreted in organ cultures from patients with H. pylori infection, and their elevation was prominent in patients with duodenal ulcer. There was a significant association between these alpha-chemokine levels and histologic grades of activity, inflammation, and H. pylori density. In fresh antral biopsies, IL-8 and GRO alpha mRNA expression was detected more frequently in H. pylori-infected patients compared with those without infection. Immunofluorescence microscopy showed localization of IL-8 and GRO alpha proteins in gastric epithelial cells and infiltrating CD68+ macrophages. In the chemotaxis assay, a significant positive correlation was found between neutrophil migration induced by the organ culture supernatants and their contents of IL-8 and GRO alpha. After H. pylori eradication, a significant decrease was observed in IL-8 and GRO alpha levels detected in organ cultures. In conclusion, mucosal alpha-chemokine activity correlates well with histologic severity of H. pylori-associated antral gastritis and can be used to predict the effects of H. pylori eradication therapy.

A Case of POEMS Syndrome Showing Elevated Serum Interleukin 6 and Abnormal Expression of Interleukin 6 in the Kidney

A 46-year-old female presented with POEMS syndrome. Hemodialysis was initiated to control severe anasarca and declining renal function. Corticosteroids were effective in treating renal insufficiency and other symptoms. Serum interleukin 6 (IL-6) was elevated before the corticosteroid therapy but returned to the normal level under the therapy. Immunostaining for the kidney tissue obtained by a renal biopsy showed a diffuse distribution of IL-6 in the glomeruli; thus, in contrast to normal, IL-6 was detected not only in mesangial cells but also in endothelial cells. IL-6 was also distributed in capillaries in the interstitium. While these results suggest a pathogenic role of IL-6 in POEMS syndrome, other factors may be necessary for the full expression of symptoms. Furthermore, it is suggested that chronically stimulated glomerular endothelial cells are capable of producing IL-6.

A case of angiotropic large cell lymphoma manifesting nephrotic syndrome and treated successfully with combination chemotherapy.

A 52-year-old female had a nephrotic syndrome without neurological or dermatological manifestations. Renal biopsy revealed that glomeruli were filled with tumor cells which bore leukocyte common antigen and pan B cell marker. These cells occupied the capillary lumen and invaded into the mesangial area. Morphological alteration of endothelial cells and glomerular basement membrane were also noticed. The interstitium was well preserved. After five cycles of a combination chemotherapy, CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone), the second biopsy revealed that tumor cells disappeared from glomeruli showing mild sclerosis. Proteinuria became absent. This is the first report of an angiotropic large cell lymphoma manifesting a nephrotic syndrome and treated successfully by CHOP therapy.

Unique glomerular lesion with spontaneous lipid deposition in glomerular capillary lumina in the NON strain of mice.

We found a strain of nonobese, nondiabetic (NON) mice which has spontaneous lipid deposition in glomerular capillary lumina. This strain was developed together with a diabetic strain of nonobese diabetic (NOD) mice for the generation of mouse models of diabetes mellitus. In the NON strain, contrary to the name, impaired glucose tolerance (IGT) was observed in about half of the mice. Meanwhile, peculiar glomerular abnormalities which remotely resemble those of diabetic nephropathy were observed in the NON strain. The lesions were characterized by massive lipid accumulation with proteinaceous material within the glomerular capillary lumina. In addition, positive staining for immunoglobulins, especially IgM, was observed by immunofluorescence microscopy. The overall frequency of this lesion was 91%. Mesangiolysis, capillary ballooning with many small lipid vesicles were the striking features by electron microscopy. Histochemical analysis revealed the presence of various lipids in these lesions. However, as far as we examined, these lesions did not correlate with hyperlipidemia or IGT. Lymphoid follicle-like structures were seen around the renal arterioles. The cellular components of these lymphoid follicles reacted with monoclonal antibodies to L3T4. High levels of serum immunoglobulins were observed in this strain. We suppose that the immunological disorders may have some bearing in the evolution of this lesion in NON mice. We believe that this model may be of use in studying the role of lipid derangements in renal diseases.

The effects of a new immunosuppressive agent, FK506, on the glomerular injury in rats with accelerated nephrotoxic serum glomerulonephritis

The aim of the present work was to study the effects of a new immunosuppressive drug, FK506, in accelerated nephrotoxic serum glomerulonephritis. Glomerulonephritis was induced in female Wistar rats by the preimmunization with normal rabbit IgG (Day-4) and the subsequent intravenous injection of rabbit anti-GBM serum (Day 0). Without treatment with FK506, rats developed proteinuria at Day 6 and onward. Rat anti-rabbit IgG was strongly detected at Day 6 and the titer was maintained through Day 20. Moderate hypercellularity and focal crescent formation were observed at Day 20. Rats injected intramuscularly with 0.3 or 1 mg/kg of FK506 did not develop proteinuria and the anti-rabbit IgG titer was much less or was undetectable throughout the experiments. These data suggest that FK506 is effective in the present model of glomerulonephritis.

Formation of subepithelial dense deposits in rats induced by a monoclonal antibody against the glomerular cell surface antigen

We developed a monoclonal antibody, H5H3, of IgG1 subclass by hybridization technique using spleen cells of mice immunized with plasma membrane fraction of isolated rat glomeruli. H5H3 recognized main bands at about 220 kD by immuno‐overlay technique and bound to the glomerulus as well as brush border of proximal tubules by indirect immunofluorescenec (IF) microscopy on normal rat kidney frozen sections. By immunoelectron microscopy (IEM) it bound to the surface of mainly glomerular epithelial cell and weakly to the endothelial cell. After injection to Wistar rats it remained granularly in the glomerulus for more than 2 weeks seen by IF. When rats were pre‐immunized with murine IgG 4 days before the injection of H5H3, mouse IgG, rat IgG and C3 were strongly visible granularly in the glomerulus in 14 days by IF. Numerous dense deposits were formed at subepithelial area seen by transmission electron microscopy. Perfusion experiment of H5H3 into rat left kidney showed granular distribution of mouse IgG in 48 h. indicating that the reaction occurred in situ. H5H3 bound diffusely in tine granular pattern on the surface of cultured glomerular epithelial cells (GEC) studied by IF and IEM. Antigenic redistribution occurred on GEC after incubation of H5H3 at 37°C. These results suggested the required conditions to form subepithetial immune dense deposits, namely that H5H3 after reaction with antigen could stay for long time in the glomerulus: that H5H3 became an antigen in autologous phase to induce large immune complexes: and H5H3 could induce antigenic modulation.