Studies on molecular markers for hemostasis and thrombosis in various renal diseases]

In order to clarify the abnormalities of blood coagulation and fibrinolysis in patients with various renal diseases, some molecular markers for hemostasis and thrombosis were examined in comparison with those of the patients with disseminated intravascular coagulation. The results were as follows: 1) PIC was significantly higher in the patients with CGN, NS, SLE, HD and DIC than normal subjects. 2) TAT was significantly higher in the patients with CGN, NS, HD and DIC. 3) SFMC was significantly higher only in the patients of DIC. 4) FDP and FDP-E were significantly higher in the patients with HD and DIC. 5) D-dimer was significantly higher in the patients with CGN, CRF, HD and DIC. These results suggested that the abnormalities of blood coagulation and fibrinolysis in patients with various renal diseases are relatively mild, and situated between the normal subjects and patients with DIC.     

Study of the changes in glomerular antigenicity in various renal diseases with anti-human renal monoclonal antibodies

We produced 22 different kinds of monoclonal antibody (Mab) by immunizing mice with human GBM antigens. In these Mabs, Mab-G1 to G5 recognized only GBM in the glomerulus, Mab-E1 and E2 recognized only glomerular epithelial cells, and Mab-M1 to M4 recognized mainly mesangium. The reactions of these Mabs with known GBM antigens such as type IV collagen, fibronectin and laminin were negative by immunoblotting. Using Mab-G1, Mab-E1 and Mab-M1, changes in the antigenicity of antigens recognized by Mabs were examined on kidney sections from the patients with various renal diseases by the indirect immunofluorescence test. When Mab-G1 recognizing GBM was used, there was no particular change of antigenicity in minimal change nephrotic syndrome (MCNS) and IgA nephropathy (IgA), whereas in membranous nephropathy (MN) thickened GBM was found to maintain antigenicity and the region of deposits was observed as negative punched-out region. In type I and III of membranoproliferative glomerulonephritis (MPGN), GBM was observed only outside of subendothelial deposits without showing double contour. In type II MPGN, GBM showed a double linear pattern and antigenicity of GBM in regions of dense deposits was not detected. When Mab-E1 recognizing glomerular epithelial cells was used, there was no change of antigenicity in the renal diseases. Further, in crescentic glomerulonephritis, the region of the cellular crescents was not stained. When Mab-M1 recognizing mesangium was used, extensive staining was observed in the increased mesangium in IgA, MPGN, and diabetic nephropathy. We feel that it is of significance in elucidating the pathogenesis of renal diseases to study the changes of glomerular antigenicity in diseased kidneys by using anti-human renal monoclonal antibodies.     

Immunohistochemical study on the extracellular matrix components in various renal diseases]

In order to clarify considerable alterations of the extracellular matrix components in various renal diseases, monoclonal antibodies against type IV collagen (IV col), 200-KD laminin (200-KD Lam), 400-KD laminin (400-KD Lam) and heparan sulfate proteoglycan (HSPG) were applied to 142 renal biopsy specimens for the indirect immunofluorescence. These subjects included 5 cases with 1 hour specimen in the transplanted kidney, 32 minimal change nephrotic syndrome (MCNS), 30 mesangial proliferative glomerulonephritis (PGN), 2 focal segmental glomerulosclerosis (FGS), 21 membranous nephropathy (MN), 9 membranoproliferative glomerulonephritis (MPGN), 2 poststreptococcal acute glomerulonephritis (PSAGN), 13 diabetic nephropathy (DN), 16 lupus nephritis (LN), 9 diffuse sclerosing glomerulonephritis (DSGN), 2 amyloid kidney and 1 granulomatous nephropathy in sarcoidosis. In the transplanted kidney, the staining intensity of IV col was stronger than that of 200-KD Lam, 400-KD Lam and HSPG in general. IV col was predominantly distributed throughout the mesangium area and less along the glomerular basement membrane (GBM). The positive stainings with 200-KD Lam along the GBM and that with 400-KD Lam in the mesangium area were weakly recognized. HSPG was mainly detected along the GBM in the linear fashion. In MCNS, the distribution of the extracellular matrix components was mostly identical to that in the transplanted kidney. In the group of the glomerulonephritis showed the proliferations of mesangial cells, such as PGN and MPGN, the staining intensity of both IV col and 400-KD Lam, particularly in the latter, was remarkably increased in the sclerotic lesions. In MN, the thickened GBM was strongly stained with both IV col and 200-KD Lam, and the stainings of 200-KD Lam were more intensive. And still more, by the double labelling method performed for the couple of IV col and immunoglobulins, the correlation between glomerular capillary walls and/or mesangial areas and immunoglobulins deposits became more clear. These findings suggest as follows: (1) both IV col and 400-KD Lam, in particular 400-KD Lam, are possibly involved in the process of glomerulosclerosis: (2) both IV col and 200-KD Lam, in particular 200-KD Lam, are greatly involved in the process of new basement membrane-like materials formation in MN.     

Studies of the analysis of urinary proteins from children with renal diseases by reversed-phase high performance liquid chromatography]

In order to analyze urinary proteins from patients with various renal diseases, a reversed-phase high performance liquid chromatography (HPLC) with IPG PACK ODS column packed with polyporous glass was used. The reproducibility of standard proteins was good. The results by this method correlated well with those by radioimmunoassay or laser nephelometry, precolumn procedure needed the centrifugation only. The reversed-phase HPLC was superior to the other HPLC methods in the analysis of urinary proteins for its simplicity and high sensitivity. The peaks of both alpha 1-acid glycoprotein (alpha 1-AGP) and human serum albumin (HSA) in the chromatogram was regarded as the marker of renal damage. Urinary alpha 1-AGP/HSA ratio was calculated after measuring these two peak areas. As a result, it was significantly higher in the urine from patients with various glomerulonephritis (GN) than in those from healthy children. In the patients with postural proteinuria, it was the same level as that in healthy children. These date suggest that the urinary alpha 1-AGP/HSA ratio would be a beneficial indicator to find out the patients with GN from among children with proteinuria. Furthermore, it seems that this method is suitable for use in routine screening of renal diseases for its simplicity and speed.     

Studies on the production of endogenous cytokines in patients with renal cell carcinoma]

This study was undertaken to determine the production of tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) by biological response modifier (BRM) in patients with renal cell carcinoma (RCC). Peripheral blood mononuclear cells (PBMC), which were donated from thirteen patients with RCC and five healthy controls, were cultured with streptococcal preparation, OK432, and/or macrophage-colony stimulating factor (M-CSF), and the TNF levels and IFN-gamma levels in the supernatant were evaluated. TNF activities were assayed by cytotoxicity to L929 cells and IFN-gamma activities were measured by inhibition of the cytopathic effects of sindbis virus on FL cells. The highest levels of TNF in the supernatant were 235.4 +/- 96.0 U/ml/1 x 10(4) cells in patients with renal cell carcinoma and 251.6 +/- 71.8 U/ml/1 x 10(4) cells in healthy controls, which were noted at 12 hours of incubation with the concentration of OK432 adjusted to 0.05 KE/ml. There was no statistically significant difference between the TNF activities induced by in vitro culture of PBMC obtained from patients with renal cell carcinoma and those from healthy controls. The production of TNF by in vitro culture of PBMC with OK432 of 0.05 KE/ml was augmented by adding 100 U/ml M-CSF especially at 48 and 72 hours of incubation, whereas M-CSF alone did not stimulated TNF production. The medium levels of IFN-gamma in six different cultures of PBMC with 0.05 KE/ml OK432 at 12, 24 and 48 hours of incubation were 1.15 +/- 0.34 U/ml/l x 10(4) cells, 2.23 +/- 0.93 U/ml/l x 10(4) cells, and 7.83 +/- 4.00 U/ml/l x 10(4) cells, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Autophagy in renal diseases

Autophagy is the cell biology process in which cytoplasmic components are degraded in lysosomes to maintain cellular homeostasis and energy production. In the healthy kidney, autophagy plays an important role in the homeostasis and viability of renal cells such as podocytes and tubular epithelial cells and of immune cells. Recently, evidence is mounting that (dys)regulation of autophagy is implicated in the pathogenesis of various renal diseases, and might be an attractive target for new renoprotective therapies. In this review, we provide an overview of the role of autophagy in kidney physiology and kidney diseases.     

Effects of age, renal diseases and diabetes mellitus on the renal size reduction accompanied by the decrease of renal function]

Renal size reduction accompanied by the decrease of renal function was evaluated by ultrasonography in 30 normal controls, 45 patients with chronic renal diseases (CRD) and 22 patients with diabetic nephropathy (DN). In controls, significant positive correlation was observed between sectional areas of right kidney and creatinine clearance (Ccr) (r = 0.794, p < 0.001), suggesting that the decrease of renal function due to aging was accompanied by the renal size reduction. Significant correlation was also found between the size and Ccr in CRD (r = 0.814, p < 0.001) and DN (r = 0.640, p < 0.01). No significant difference was observed between controls and CRD in the reduction rate of renal size per unit change of Ccr, which suggested that the renal size reduction accompanied by the decrease in Ccr was the same in controls and CRD. In contrast, in DN, renal size reduction accompanied by the decrease in Ccr was smaller than controls or CRD. When renal sizes were compared in patients, whose Ccr were equal or less than 20 ml/min, renal sizes were significantly larger in DN than CRD (p < 0.001). The duration of illness from the onset of proteinuria was longer in CRD than DN (13.5 years and 4.7 years, respectively). The difference of renal sizes, however, can not be fully explained by the differences in the length of illness, since the renal size was larger in DN than CRD even when we compared the patients with the similar length of illness. In conclusion, renal size decreased with the reduction in the renal function in controls, CRD and DN.(ABSTRACT TRUNCATED AT 250 WORDS)     

Studies on vessel invasion by cancer of the renal pelvis and ureter]

The significance of vessel invasion by cancer of the renal pelvis and ureter was estimated with surgical specimens of 45 patients. The vessel invasion by cancer was observed in 25 out of 45 cases (55.6%). The incidence of vessel invasion increased with the grade of cancer and the extent of the primary tumor. The postoperative metastases by cancer was noted in 22 of the 25 patients with vessel invasion (88%) and in 4 of 20 (20%) patients without vessel invasion. The incidence of metastases in patients with vessel invasion was significantly higher than that without it (p < 0.01). The 5-year survival rate was 13.1% in the patients with vessel invasion and 80.6% in the patients without it (p < 0.005). Postoperative chemotherapy had no effect on the unfavorable outcome of the patients with vessel invasion. Therefore, vessel invasion by cancer may be one of the prognostic factors in renal pelvic and ureteral cancer. The patients with vessel invasion should be treated with more aggressive therapy to improve the poor prognosis.     

Drug-induced renal diseases

Drugs causing renal damage and the clinicopathological forms of the diseases are described. Attention is called to the importance of drug-induced renal diseases.