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 glomerulas, 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 anti-genicity in minimal change nephrotic syndrome (MCNS) and IgA nephropathy (IgA), whereas in membranous nephropathy (MN) thickened GBM was found to maintain anti-genicity 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 subendothlial 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 glomerulone-phritis, 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.

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Using a monoclonal antibody (Mab-G3) recognizing glomerular basement membrane (GBM), we assayed GBM antigen (G3-Ag) in the urine and serum of renal disease patients by sandwich ELISA. The subjects included normal control (NOR), minimal change nephrotic syndrome (MCNS), IgA nephropathy (IgA), membranous nephropathy (MN), membranoproliferative glomerulonephritis (MPGN) and chronic renal failure (CRF). The urine and serum was used as the material. With urinary G3-Ag, there were no statistically significant differences among the NOR, MCNS, IgA, MN, MPGN and CRF groups. Although no correlation was observed with proteinuria, hematuria, serum creatinine, serum β2 microglobulin and urinary NAG, urinary G3-Ag showed a significant (p<0.05) increase in excretion in the group of progressive CRF patients with s-Cr more than 1.0 mg/dl/month as compared to the stationary CRF group with s-Cr<1.0 mg/dl/month. Serum G3-Ag showed lower values in almost all cases, and there were no significant differences among the renal disease groups. The above findings led us to believe that the assay of urinary G3-Ag was useful in determining the degree of GBM disorder. It was also presumed that assay of renal antigens in urine and serum with the respective anti-human renal monoclonal antibodies could be a new tool in diagnosing renal diseases.

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C3 nephritic factor (C3 NeF) has been found mainly in the sera of patients with membranoproliferative glomerulonephritis (MPGN) and partial lipodystrophy (PLD). We examined whether peripheral blood mononuclear cells (PBMC) from patients with PLD and MPGN could produce C3 NeF. We investigated the in vitro immunoglobulin synthesis of PBMC with mitogen. We further studied whether or not C3 NeF was included in the IgG of the culture supernatants by the C3bBb stabilizing activity and agglutination assay. The IgG of PLD patient was able to agglutinate only EAC4bBb cells and none of the other intermediate cells. We thus demonstrated that C3 NeF could be produced in vitro by PBMC derived from the patient with PLD. However, as regard case of C3 NeF weakly positive and C3 NeF negative patients, C3 NeF couldn't be produced in vitro by PBMC derived from the patients.

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Urinary protein fractions and clinicopathological features in 80 patients with IgA nephropathy, who had mild proteinuria (0.60±0.35 g/day) less than 2 g/day, were analyzed. Urinary protein fractions was determined with SDS-polyacrylamide microgel electrophoresis (SDS-PAGE). The patterns on the densitogram of SDS-PAGE were divided into 4 groups, that is, normal pattern (Group I: N=4), low molecular weight proteins (LMWP) predominant pattern (Group III: N=29) and high molecular weight proteins (HMWP) excessive pattern (Group IV: N=28). Histological changes were minor in majority of Group I but gradually increased in Group II, III and IV. Especially in Group IV, global sclerosis (78.6%; vs. Group II: p<0.01, vs. Group III p<0.05), small crescent (57.1%; vs. Group II : p<0.05), adhesion (60.7%; vs. Group II : p<0.05), mesangial proliferation (96.4%; vs. Group II : p<0.01, vs. Group III : p<0.05) and tubulointerstitial degeneration (85.7%; vs. Group II and III : p<0.05) were most predominant. These results indicate that urinary protein fractions and histological changes appear to correlate closely in IgA nephropathy with mild proteinuria, and that marked HMWP is considered to be an early marker of glomerular damage in the prognosis of IgA nephropathy.

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Forty-seven patients with IgA nephropathy were clasified as having mesangial pattern (M: 29 cases) or mesangiocapillary pattern (C: 18 cases) according to an intraglomerular distribution of fibronectin (FN) observed by the immunofluorescence (IF) technique. The relationships between these IF patterns and the clinical pictures, and that between these IF patterns and prognosis of the disease were investigated. Significantly higher diastolic blood pressure, proteinuria, serum creatinine (Cr), total cholesterol and IgA, and lower total protein were noted in C pattern as compared with M pattern. β-thromboglobulin, fibrinogen (Fib) and platelet factor 4 were found to be significantly higher in C pattern. Platelet aggregation (ADP 1μM/ml) and FN tended to increase (p<0.1) as well. The distribution of FN in the glomeruli was similar to those of IgA and Fib, althongh perfect agreement was not observed. The picture in which FN might be infiltrated into the endothelial side of the glom-erular basement membrane from the mesangium was observed in C pattern by the immunoelectron microscopic study. In the follow-up study, proteinuria showed a tendency to decrease in M pattern. On the other hand no marked change was observed in C pattern. C pattern showed high serum Cr levels throughout the course of the study as compared with M pattern. A significantly greater number of C pattern cases had serum Cr of 2 mg/dl or higher, C pattern showed a significant decrease of 1/Cr over time as compared with M pattern. Higher serum Fib and FN, platelet aggregation (ADP 1μM/ml), antithrombin III and plasminogen were observed in C pattern as compared with M pattern. These results suggest that an involvement of tissue FN, especially the existence of FN in the capillary loop, may be an aggravating factor of IgA nephropathy, in addition to an augmented platelets-blood coagulation mechanisms. Therefore, it may be possible to evaluate the prognosis of IgA nephropathy by FN deposit patterns.

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The purpose of the present study is to determine polyols and sugars in glomeruli obtained from streptozotocin (STZ) diabetic rats. Sixty milligram per kg body weight of STZ was injected to Sprague-Dawley male rats and then the aminals were sacrificed 4 and 12 weeks after the injection. One group of STZ diabetic rats was treated with 8-14 units of NPH insulin for 3 weeks. Glomeruli were isolated by sieving methods. The concentration of polyols and sugars was measured by gas chromatography mass spectrometry. The levels of glucose, sorbitol, fructose, mannose, ribitol and erythritol in the glomeruli were significantly higher in 4- or 12-week diabetic rats than those in control rats, whereas the level of scyllo-inositol was decreased. In insulin treated 4-week diabetic rats, the levels of all polyols but scyllo-inositol were significantly decreased compared with un-treated diabetic rats. The level of myo-inositol in glomeruli of 12-week diabetic rats was significantly higher than those of control rats, whereas that of erythritol was decreased. The urinary N-acetyl glucosaminidase activity as well as creatinine clearance was increased in 4- and 12-week diabetic rats. Urinary protein was also increased in 12-week diabetic rats. These findings suggest that the alterations of polyol metabolism in glomeruli of dia-betes may play an important role in the pathogenesis and/or progression of daibetic nephropathy. It is likely that treatment with insulin improves the alteration of polyol metabolism in the glomeruli in early stages of diabetes.

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We evaluated a new automated biopsy device for percutaneous renal biopsies under ultrasound guidance, which was recently introduced in Japan for prostate biopsies. This device (Biopty-Gun : Bard Biopty Instrument Uppsala, Sweden) employs a Tru-Cut type smaller needle (18 gauge). We were able to obtain one or two renal tissues in all 57 cases with great ease and in little time. The length of specimen was sufficient (5-17 mm), but the width was thinner than the samples with the Vim-Silverman or Tru-Cut needles. We could achieve a definitive pathological diagnosis in 54 of 57 cases (94.7%), but now, we try to obtain two pieces of tissue for taking more adequate tissue. Only three patients had perirenal hematomas noted by computerized tomography or ultrasonography. We believe that this new automated technique offers a safer and more effective means of obtaining renal tissue.

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We assessed the clinical usefullness of Biopty biopsy instrument & Bioty biopsy needle in percutaneus renal biopsy (PRB) compared with Tru-cut disposable needle and Vim-Silvermann needle. Sixty cases, each consisting 20 cases, were performed PRB by 3 different needles. There was no significant differences between Biopt y-cut needle and Tru-cut needle in the length of renal biopsy tissue and number of glomeruli obtained. The frequency of clinical complications such as fever, flank pain and decrease in Ht>2% was lower in Biopty needle group after PRB. The frequency of middle and large size of hematoma was also lower in Biopty needle group after PRB. We could also obtain specimen from transplated kidney without complications except small hematoma. From-three results, Biopty biopsy needle is a useful tool in performing PRB.

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This study was performed to clarify serum beta-2 microglobulin (β₂-M) level and its change in 50 CAPD and 56 HD patients. There was significant correlation between duration of dialysis and serum β₂-M level in CAPD and HD patients treated under 12 months, but no correlation in those treated over 12 months. Serum β₂-M level was 33.5±9.1 mg/l in 45 CAPD patients treated over 12 months, and 46.2±21.1 mg/l in 35 HD patients. In 26 CAPD patients treated over 12 months, clearance and removal of β₂-M were 1.0±0.3 ml/min and 43.0±17.8 mg/day. There was significant correlation between dwell time and β2-M removal (p<0.01), and these results suggested β₂-M was removed by diffusion. Because CAPD treatment can lower serum β₂-M level compared to HD, there is possibility that CAPD is useful at prevention of dialysis associated amyloidosis.

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Effect of renin inhibitor ES-1005 or captopril on the renin synthesis by the kidney was investigated in sodium-depleted marmosets. The level of kidney renin mRNA was measured after 2-hour (acute study) and one-week (chronic study) administrations of the two agents. Relative amounts of kidney renin mRNA were measured by densitometric Northern blot analysis using an α-³²P-labelled human renin cDNA fragment as a hybridization probe. In the acute study, treatment with captopril significantly increased plasma renin activity (PRA) (p<0.05), but did not change the level of kidney reamn mRNA. In the chronic study, treatment with captopril markedly increased PRA as well as the level of kidney renin mRNA (4.7-fold and 6.3-fold increases, respectively). In contrast, treatment with ES-1005 completely inhibited PRA and significantly suppressed the level of kidney renin mRNA in both acute and chronic studies (about one-third of the normal control, p<0.05). These results suggest that renin inhibitor ES-1005 not only inhibits plasma renin activity but also suppresses the synthesis of renin by the kidney.

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A 54 year-old woman who had had 4 years history of ulcerative colitis (UC) was admitted to our hospital because of recently developed proteinuria and leg edema. On admission, laboratory findings disclosed massive proteinuria, hypoalbuminemia, accelera-tion of ESR and elevated of CRP. Her abdominal symptom was remmited. Renal biopsy showed amyloid deposition in glomeruli and arteriole. Amyloid deposition was also found on rectal biopsy. She had no evidence of familial amyloidosis and multiple myeloma. In this case, amyloid deposition might be developed after UC. Secondary amyloidosis due to UC was extremely rare, only 3 cases including ours were reported in Japan.

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A case of SLE with moderately deteriorated renal function due to lupus nephritis developed cryptococcal meningitis. Long term administration of amphotericin B (cumulative dose 5g) combined with 5-flucytosine eradicated this fungal infection. Throughout amphotericin B administration urinary excretions of Na and K, as well as plasma HCO₃ concentration were monitored, and, Na, K and HCO₃ were supplemented orally and intravenously so much as to replace their urinary losses. Neither prominent water-electrolyte disturbace nor severe azotemia, which are the most serious side effects of amphotericin B, did not ensue. This case study indicates that sufficient water-electrolytes supplementation is im-portant to prevent the nephrotoxicity of amphotericin B.

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