Shigeru Tomizawa

Studies of Vascular Permeability Factor derived from T Lymphocytes and Inhibitory Effect of Plasma on Its Production in Minimal Change Nephrotic Syndrome

Peripheral T lymphocytes from patients with minimal change nephrotic syndrome (MCNS) and controls were treated for their ability to produce vascular permeability factors (VPF) without concanavalin A stimulation. In vitro cultures of T lymphocytes from active MCNS produced VPF in the supernatant, whereas T lymphocytes from inactive MCNS or normal subjects did not. Furthermore, the plasma from patients with active MCNS markedly inhibited VPF production when compared with plasma taken from inactive MCNS or fetal calf serum alone. However, the plasma from MCNS in neither the active nor the inactive stage had any direct blocking effect on VPF activity. These results seem to suggest that the plasma from patients with MCNS in the active stage inhibits VPF production, but does not neutralize T lymphocytes derived VPF activity.

Effect of Supernatants Derived from T Lymphocyte Culture in Minimal Change Nephrotic Syndrome on Rat Kidney Capillaries

The effect on the kidney capillaries of T lymphocyte culture supernatants from patients with minimal change nephrotic syndrome was studied by infusion into the left renal artery of rats. The supernatants of T lymphocyte cultures from nephrotic patients induced significant proteinuria and a reduction of anionic sites in the glomerular basement membrane of the kidneys in the rats. These changes were not produced in rats receiving equivalent supernatants from healthy controls.

Inhibition of Vascular Permeability Factor Production by Ciclosporin in Minimal Change Nephrotic Syndrome

In order to ascertain whether ciclosporin (Cs) has an inhibitory effect on the vascular permeability factor (VPF) production, various quantities of Cs were added to T lymphocyte cultures from 8 children with minimal change nephrotic syndrome (MCNS) and the VPF activity of culture supernatants was assayed. As a result of the addition of Cs, a dose-dependent inhibition of VPF production was seen. VPF production was inhibited by a level of between 100 and 250 ng/ml of Cs in vitro. The reduction of proteinuria by Cs in MCNS might be due to the inhibition of VPF production.

Lipoprotein glomerulopathy: a pediatric case report

Abstract. We report an 8-year-old girl with lipoprotein glomerulopathy who may have developed this condition as young as 4 years of age. To our knowledge this is the youngest reported case of this disease. Lipid studies of the patient and her family members revealed elevated concentrations of apolipoprotein E (apo E), the apo E phenotype E2/3, and the genotype E3/3. However, other families revealed no urinary abnormalities. Our findings suggest that an apo E abnormality may be responsible for the development of lipoprotein glomerulopathy. Genetic analysis of apo E is needed to clarify the pathogenesis.

Studies of T Lymphocyte Function and Inhibitory Factors in Minimal Change Nephrotic Syndrome

Plasma obtained from patients with MCNS in active stage suppressed the 3H-TdR incorporation of autologous or homologous lymphocytes stimulated with PHA-P and E rosette formation, while plasma from patients in remission did not. The depressed mitogenic response of lymphocytes from patients in the active stage significantly improved when the patients plasma was substituted for the plasma from inactive MCNS or healthy persons and fetal calf serum. In the preliminary experiment, it was seen that the inhibitory factors were heat stable at 56 degrees C, unadsorbable to charcoal powder and retained in both the permeable and impermeable fractions of collodion bag.

Release of the vascular permeability factor in minimal change nephrotic syndrome is related to CD4+ lymphocytes.

Shigeru Tomizawa, MD, Department of Pediatrics, Gunma University School of Medicine, Maebashi, Gunma (Japan) Dear Sir, The production of the vascular permeability factor (VPF) from peripheral blood T lymphocytes in nephrotic patients has been confirmed by both Heslan et al. [1] and ourselves [2]. Furthermore, the appearance of significant proteinuria and reduction of anionic sites in the glomeru-lar basement membrane of rat kidneys after infusion of the supernatant of T lymphocyte cultures from minimal change nephrotic syndrome (MCNS) has been demonstrated [3]. Nevertheless, the identity of the T lymphocyte subset which releases the VPF has remained obscure. For the determination of the VPF released from T lymphocyte subsets, we investigated 8 nephrotic children in active and untreated stages. The peripheral hepari-nized venous blood was separated by Conray-Ficoll gradient. The mononuclear cells were filtered through a nylon wool column. The collected T cell-rich fractions were mixed with monoclonal anti-OKT4 or antiOKT8 antibody, and incubated for 30 min at 4 °C. After the cells had been washed with PBS 3 times, they were incubated with 50 μl rabbit complement for 30 min at 37 °C, and washed again with PBS 3 times. Cell viability was controlled with trypan blue exclusion dye. T cell subset content of the fractionated cell samples was checked by a cell sorter, after staining with monoclonal anti-OKT3, anti-OKT4 or anti-OKT8 antibodies. The percentage of CD3 + cells in the T cell-rich fraction was more than 90%, and that of CD4 and CD8 cells in T cell-rich fraction was 75 and 80%, respectively. Each cell sample was cultured in RPMI 1640 at a concentration of 1 × 10/ml at 37 °C and 5% C02 humidified atmosphere. After 48 h of culture, the supernatants were removed and stored at -80 °C until use. The VPF assay on guinea pig skin was assessed according to Ovary’s method [4]. The diameter of the blue area surrounding each injected sites was measured and the area of blueing calculated. For statisti-

Reversed – Phase High – Performance Liquid Chromatography for Analysis of Urinary Proteins: Diagnostic Significance of α1-Acid Glycoprotein

In order to analyze urinary proteins from patients with various renal diseases, a reversed-phase high-performance liquid chromatography with IPG PACK ODS column packed with polyporous glass was employed. The peak areas of alpha 1-acid glycoprotein (alpha 1-AGP), beta 2-microglobulin (beta 2-MG) and albumin were measured by a chromato-integrator. The alpha 1-AGP/albumin ratio was regarded as the marker of glomerular damage, while the beta 2-MG/albumin ratio indicated tubular dysfunction. As a result, the alpha 1-AGP/albumin ratio in the urine from patients with either various glomerulonephritis (GN) or idiopathic nephrotic syndrome was significantly higher than that from either patients with postural proteinuria or healthy children. However, the beta 2-MG/albumin ratio in the urine from patients with GN was the same level as controls. The beta 2-MG/albumin ratio was elevated only in urine from patients with tubular dysfunctions. These data suggest that the urinary alpha 1-AGP/albumin ratio could be a beneficial indicator in locating patients with GN from among children with asymptomatic proteinuria.

Purification of Two Types of TNF Inhibitors in the Urine of the Patient with Chronic Glomerulonephritis

In order to clarify whether TNF inhibitory activity in the urine of glomerulonephritis (GN) patients depends on the existence of TNF inhibitors/soluble TNF receptors, we purified two types of TNF inhibitors from the urine of chronic renal failure (CRF) with GN patient. Using four steps of chromatography (anion exchange chromatography, preparative reverse phase chromatography, TNF affinity chromatography, analytical reverse phase chromatography), two types of 99% pure TNF inhibitors were purified. Amino terminal amino acid sequence revealed that one inhibitor was identical to soluble TNF receptor, p55, however, the other was homologous but not identical to soluble TNF receptor, p75. Our experiments demonstrated that TNF inhibitory activity in the urine of CRF patients depended partly on the existence of soluble TNF receptors in the urine.

Differences in Level and Avidity of Secretory IgA Antibodies in Breast Milk of Swedish, Indian and Japanese Mothers to Soybean Protein

Colostrum was collected from Swedish, Indian and Japanese mothers. The samples were as a mean, collected 4.00-4.25 days after delivery of term infants. The level of specific IgA antibody to 2S, 7S and crude soybean antigen were measured by the enzyme-linked immunosorbent assay (ELISA). The avidity of the IgA antibodies to 7S soybean antigen was also measured with an ELISA system using different molarities of potassium thiocyanate for elution of the specific IgA antibody from solid phase-bound antigen. The level of specific IgA antibody to 7S and crude soybean antigen in the milk of the Indian mothers was significantly higher than in the milk of the Japanese mothers (p less than or equal to 0.01). In contrast, the avidity expressed as the molarity of KSCN for 50% elution of IgA antibody to 7S soybean antigen in the milk of the Japanese mothers was significantly higher than in the milk of the Indian mothers (p less than 0.01).

C9 deficiency in a patient with poststreptococcal glomerulonephritis

The case of a 10-year-old girl with congenital C9 deficiency and poststreptococcal glomerulonephritis (PSGN) is presented. Although her clinical symptoms mimicked those of Henoch-Schönlein purpura, histological examination of a renal biopsy specimen revealed the features commonly described in PSGN.