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We developed a sensitive method for detection of glycosphingolipid (GSL) antigen(s) on the cell surface. As a model of GSL antigen, ganglioside GD3 was used. An IgM monoclonal antibody (DSG-1) specific for ganglioside GD3 was preincubated with standard inhibitor liposomes containing ganglioside GD3. Then carboxyfluorescein-entrapped indicator liposomes containing ganglioside GD3 and complement were added. Release of the marker from the indicator liposomes was specifically inhibited by inhibitor liposomes. The assay system was simple, sensitive, reproducible, and semiquantitative. Pg to ng of ganglioside GD3 could be detected. Furthermore, ganglioside GD3 on the cells was investigated with SK-MEL-28 human melanoma cell line and human red blood cells (HRBC). When SK-MEL-28 melanoma with ganglioside GD3 was used as an inhibitor, specific inhibition was observed. However, HRBC without ganglioside GD3 showed no significant inhibition. The marker release was 50% inhibited by 1.4 x 10(6)SK-MEL-28 melanoma cells/ml. The amount of ganglioside GD3/melanoma cell was estimated to be at least 1.1 x 10(-14) g from the standard curve made with the liposomes containing 10% epitope density of ganglioside GD3. This assay system may be useful for detection of GSL antigen on the cell.

Southern blot hybridization was used to detect the rearrangement and amplification of five proto-oncogenes (bcl-2, bcl-1, c-myc, c-myb and c-Ha-ras) and one tumor suppressor gene (RB-1) in 55 Japanese patients with non-Hodgkin's lymphoma; 16 with T-cell lymphomas and 39 with B-cell lymphomas (7 follicular and 32 diffuse lymphomas). Genetic abnormalities of the proto-oncogenes were detected in 7 of the 55 (13%). Genetic abnormalities of bcl-2 plus other genes were detected in 5 of 7 cases of follicular lymphoma (71%), rearrangements of bcl-2 and c-myc, rearrangement of bcl-2 and amplification of c-myb. Genetic abnormalities were observed in only three cases of diffuse lymphoma. In each of 3 cases of B-cell lymphoma, one of the genes, blc-2 mbr, bcl-2 mcr and c-myc, was rearranged respectively. The incidence of genetic abnormalities in diffuse lymphomas (6.3%) was lower than that in follicular lymphomas. None of diffuse lymphomas had double oncogene abnormality. No abnormalities were found in RB-1, bcl-1, and Ha-ras. These findings suggest that follicular lymphomas are associated with some abnormalities of oncogenes not restricted to bcl-2 that facilitate growth which may be associated with their clinical features.

Serum levels of total IgE, specific IgE, IgG and IgG4 against house dust mite were measured in mite-sensitive asthma patients receiving immunotherapy with house dust. Serum levels of total IgE, mite specific IgE and IgG did not significantly change during the course of hyposensitization. Increased levels of mite specific IgG4 were observed in patients during immunotherapy. The increase in specific IgG4 was dependent on the total dose of house dust administered in both children (r = 0.636, p less than 0.001) and adults (r = 0.629, p less than 0.01). However, the increase of specific IgG4 in adults was not as apparent as in children. These results might suggest that mite specific IgG4 is a useful immunological marker in the immunotherapy for allergic asthma, and that IgG4 antibody acts as a blocking antibody in atopic bronchial asthma.

To identify ARIX gene and PHOX2B gene polymorphisms in patients with congenital superior oblique muscle palsy, 3 exons of the ARIX gene and PHOX2B gene were sequenced by genomic DNA amplification with polymerase chain reaction (PCR) and direct sequencing in 31 patients with congenital superior oblique muscle palsy and in 54 normal individuals. A family with a father and one daughter each having congenital superior oblique muscle palsy was also included in this study. Eleven patients with congenital superior oblique muscle palsy had heterozygous nucleotide changes in the ARIX gene, including 4 patients reported on previously. One patient with atrophy of the superior oblique muscle had a new change of T-4G in the promoter region of the ARIX gene. The other 6 patients had a heterozygous nucleotide change of G153A in the 5'-untranslated region (UTR) of the exon 1 of the ARIX gene. These nucleotide changes of the ARIX gene, taken together, had a significant association with congenital superior oblique muscle palsy(P = 0.0022). One patient and 5 patients had heterozygous nucleotide changes of A1106 C and A1121 C in exon 3 of the PHOX2B gene, respectively, while these changes were absent in the normal individuals. Two patients had both the G153A change in the 5'-UTR of exon 1 of the ARIX gene and the A1121 C change in exon 3 of the PHOX2B gene. In conclusion, the polymorphisms of the ARIX gene and PHOX2B gene may be genetic risk factors for the development of congenital superior oblique muscle palsy.

Metaplastic bony tissue along with hyperplastic mucosal epithelium showing no atypism was detected in biopsy materials from a Yamada type I gastric polyp. The tissue was metaplastic woven bone associated with calcification. Histogenesis of the bone formation is as yet unknown. This is the first reported case of the presence of metaplastic bone accompanied by hyperplastic gastric mucosa so far.

A significant amount of anticoagulant substance was released along with histamine, when human lung mast cells were stimulated with anti-IgE and Ca-ionophore A23187. Its activity was lost by heparinase, not by chondroitin-ABC lyase or chondroitin-AC lyase, and also inhibited by Polybrene, suggesting it would be heparin.

To confirm the formation of Charcot-Leyden crystals (CLC) in basophils, we observed basophils in sputum and peripheral blood. Sealed slide and suspension culture methods were used to observe the process of CLC formation in peripheral blood basophils and eosinophils under electron microscopy. CLC formation was observed in basophils and eosinophils, and was found to be augmented by sealed slide method. A temperature of 4 degrees C was better than 37 degrees C for promoting the formation of crystals. There was no correlation between the degranulation of these cells and the formation of CLC after stimulation with anti-IgE or anti-IgG antibodies. CLC were initially detected in the cytoplasmic granules of basophils where they continued to enlarge. No CLC were identified in mast cells under any conditions studied. These findings confirm that CLC in sputum are not exclusive to eosinophils and that CLC appear to be present in basophil-rich sites under the cell damage.

Candida albicans-induced histamine release from basophils was studied in 54 patients with bronchial asthma in comparison with the release caused by house dust and anti-IgE. The release of histamine induced by C. albicans and that induced by house dust were closely related to the serum levels of specific IgE antibodies as expressed by RAST scores. A correlation of C. albicans-induced histamine release with the release caused by anti-IgE was not generally observed. On the other hand, a close correlation was found between house dust- and anti-IgE-induced histamine release. It was suggested from these results that the differences between C. albicans- and house dust-induced histamine release might be due to the different antigenicity of the two allergens.

The inhibitory effect of nicardipine, a calcium antagonist, on the antigen- and anti-IgE-induced histamine release from basophilic leucocytes of patients with bronchial asthma was examined. The agent significantly inhibited both antigen-stimulated and anti-IgE-induced histamine release from basophils (the maximum percent inhibition was 57.8 +/- 7.2% and 56.0 +/- 8.8%, respectively). Pre-incubation of basophils with nicardipine for periods of up to 120 min did not alter the inhibitory effect. These results suggest that nicardipine modifies the histamine release from basophils which closely participate in an attack of bronchial asthma.

A carboxyfluorescein (CF)-enveloping soybean phosphatidylcholine liposome was used as a model of physicochemical damage of biomembranes. The liposomes were exposed to a metal-chelate complex [2 mM of ferric nitrilotriacetate (FeNTA) or cupric nitrilotriacetate (CuNTA)] plus a reductant (2 mM of ascorbate or various concentrations of reduced glutathione), and CF release from damaged liposomal membranes and the generation of thiobarbituric acid-reactive substances (TBARS) were measured. In the presence of a reducing agent, both FeNTA and CuNTA stimulated markedly CF release and an increase in the TBARS level, while in the absence of a reducing agent both of the chelate complexes showed little CF release and TBARS. The effects of H2O2 addition to the reaction system containing liposome with FeNTA or CuNTA plus ascorbate were also examined. The CF release was slightly increased by the addition of a smaller dose (0.5 mM) of H2O2 and it was inhibited by 8 mM of H2O2. A similar result was obtained in the TBARS test. These results suggest that FeNTA- or CuNTA-mediated lipid peroxidation can damage liposomal membranes physicochemically, and the redox reaction of the chelated metal itself is more important than a Fenton-type reaction in the process.

Previously, we reported that interleukin-2 (IL-2)-stimulated helper T cells produced an unknown soluble factor which induced dendritic cell-like differentiation in primary cultures of monocytic leukemia cells and we referred to this factor as dendritic cell differentiation factor (DCDF). In this study, we attempted to purify and characterize DCDF and investigated its biological effect on normal human monocytes. Gel filtration chromatography indicated that the molecular weight of DCDF is approximately 30-35 kDa. Chromatofocusing indicated that the isoelectric point of DCDF is approximately 5.0. DCDF, partially purified by subsequent gel filtration, chromatofocusing, and hydrophobic chromatography, significantly enhanced the HLA-DR expression of normal human monocytes and a human monocytic leukemia cell line, THP-1. This biological activity was not neutralized by any known antibodies to human cytokines. DCDF significantly amplified the T-cell stimulatory activity of monocytes in the allogeneic mixed leukocyte reaction (MLR). Moreover, DCDF significantly enhanced IL-1 beta and IL-6 production by monocytes in a dose-dependent manner. These results suggest that DCDF is a novel human cytokine which stimulates the accessory cell function of monocytes.

We have already developed the liposome immune lysis assay (LILA) for the determination of C-reactive protein (CRP) by employing an inhibition method and a sandwich method. We herein report a new LILA system involving the use of monoclonal antibodies-bearing liposomes. We established five monoclonal antibodies to CRP antigen, AC-1, -2, -3, -4, -5 which had the capacity to activate complement and form antigen-antibody complex. Each of these antibodies was covalently coupled to carboxyfluorescein-entrapped multilamellar liposomes. When the liposomes were incubated with CRP antigen in the presence of guinea pig complement, CRP antigen-dependent liposome lysis was observed but the sensitivity was not great enough for practical use. On the other hand, when liposomes coupling two monoclonal antibodies (AC-1, AC-2) which recognized distinct CRP antigenic determinants were employed in the assay, the sensitivity increased compared with that using only one monoclonal antibody, and the detectable concentration range was 5-300 ng/ml. These results indicated that the combination of two or more monoclonal antibodies which recognize distinct CRP antigenic determinants is effective for increasing the sensitivity of the assay.

The sensitivity and specificity of single cell polymerase chain reaction (PCR) were studied. Its high sensitivity enabled detection of a single-copy gene, such as human T-lymphotropic virus type I genome in paraffin sections. The rate of obtaining positive signals with this method was affected by the number of copies of the gene in the target cell. Specificity was satisfactory if the procedure was properly and carefully followed. Since the single cell PCR is a time-consuming method which requires skill and experience to pick up the target cells accurately, the applicability of this method is limited. It works best when it is used to analyze a single or a few copy genes in histologically identified cells.