Squamous cysts in renal dysplasia.
We report two cases of renal dysplasia with squamous cysts. The histological features in one case suggest that the cysts may develop through metaplasia of the tubular epithelium.
Humans↗
Biomedical subjects
J K Chan
Publications and source records attributed to J K Chan.
A comparison of immunofluorescent assays to detect anti-granulocyte antibodies.
Three immunofluorescent assays were compared to detect anti-granulocyte antibodies (AGA) in patients with immune disorders: the granulocyte immunofluorescence test (GIFT), the avidin-biotin coupling test (ABCT), and the modified staphylococcal protein A test (MSPAT). The ABCT was more sensitive than both the GIFT and MSPAT for patient sera, but it also detected more positivity among random normal sera. Although less sensitive than the ABCT, the GIFT and MSPAT showed greater specificity and higher predictive values for positivity. When normal lymphocytes were run in parallel with normal granulocytes, 68% of positive AGA sera were nonreactive with lymphocytes, indicating the antibody specificity for granulocytes. Comparison of three direct and indirect immunofluorescent assays suggested a general co-existence of both cell-bound and circulating AGA. However, the direct test displayed minimal amounts of fluorescence for negative controls in contrast to the variable levels of fluorescence seen in normal sera for the indirect test.
Autoantibodies↗
Anticardiolipin antibodies in autoimmune thrombocytopenic purpura.
Using a recently devised solid phase radioimmunoassay to detect anticardiolipin antibodies, we report the presence of these antibodies in 30 of 96 patients with chronic autoimmune thrombocytopenic purpura (AITP). IgG anticardiolipin antibody levels were elevated in 14 patients and IgM anticardiolipin antibody levels were elevated in 27 patients. We suggest that these antibodies may mediate peripheral platelet destruction by binding to phospholipids in the platelet membrane. It is also conceivable that the presence of anticardiolipin antibodies may select a subpopulation of patients with chronic AITP who may go on to develop other autoimmune disorders, such as systemic lupus erythematosus.
Antibodies↗
Anticardiolipin antibody, recurrent thrombosis, and warfarin withdrawal.
Antibodies to cardiolipin, closely related to the 'lupus anticoagulant', are strongly implicated in the pathogenesis of thrombosis. We record six patients, all with high titres of these antibodies (greater than SD) in serum, who developed recurrent vascular occlusions six to 12 weeks after warfarin withdrawal. Five of the six had deep vein thrombosis, while the sixth suffered a myocardial infarction. To minimise the risk of 'recurrent' thrombosis it is strongly suggested that such patients remain on long-term anticoagulation, pending the reduction of high antibody levels.
Adolescent↗
HLA-DR synthesis induction and expression in HLA-DR-negative carcinoma cell lines of diverse origins by interferon-gamma but not by interferon-beta.
De novo synthesis of major histocompatibility complex (MHC) class II antigens was induced by affinity-purified preparations of interferon (IFN)-gamma, but not by IFN-beta (as judged by the criteria of cell surface expression and protein synthesis) in human osteogenic sarcoma, colorectal carcinoma, and melanoma cell lines that were not constitutive producers of these antigens. The synthesis of heavy-chain and light-chain (beta 2-microglobulin) components of MHC class I antigens was enhanced by both IFN-gamma and IFN-beta; IFN-gamma showed the greater activity. IFN-gamma and IFN-beta also enhanced the expression of class I antigens on the plasma membrane in a dose-dependent manner; IFN-gamma was again the more active agent. Only IFN-gamma induced the membrane appearance of class II antigens in cell lines that appeared negative for HLA-DR expression by all criteria. However, in SW480 cells, which spontaneously express low levels of HLA-DR, IFN-gamma and IFN-beta both enhanced the expression of class II antigens. These results suggest that IFN of both types amplify the products of actively transcribed genes, but that type II IFN is unique in its capacity to induce HLA-DR expression in nonconstitutive cell lines. Kinetic studies showed that enhancement of class I membrane expression preceded the induction of class II expression and peaked earlier. The specificity of these responses was underlined by the inability of either IFN to enhance the synthesis or expression of the tumor-associated membrane glycoprotein gp22. The data indicate that tumor cell lines of diverse tissue origin that do not synthesize or express class II antigens by the criteria of immunoprecipitation or monoclonal antibody binding can be induced to do so by IFN-gamma and may therefore be subject to therapeutic and immunoregulatory modulation.
Antigens, Neoplasm↗
Crossreactivity of antiphospholipid antibodies.
Using a solid phase radioimmunoassay to detect anticardiolipin antibodies, the crossreactivity of these antibodies with phospholipids and DNA was tested in 10 patients with autoimmune disorders and 1 patient with secondary syphilis. The crossreactivity of anti-ds DNA and anti-ss DNA antibodies with cardiolipin was tested in 10 additional patients with SLE. In the 10 sera tested with high anticardiolipin antibody levels, there was marked inhibition of anticardiolipin antibody activity by negatively charged phospholipids. The zwitterionic phospholipids inhibited anticardiolipin antibody activity in some sera, and in instances where this occurred, inhibition was less than that obtained for the negatively charged phospholipids. There was minimal inhibition of anticardiolipin antibody by ss DNA in only 2 of 10 sera tested and no inhibition by ds DNA in any sera tested. Conversely, cardiolipin inhibited anti-ss DNA antibody activity in 2 of 10 sera, and anti-ds DNA antibody activity in 2 of 10 sera tested. There was no correlation between anticardiolipin antibody levels and either anti-ds DNA or anti-ss DNA antibody levels. These results suggest that antiphospholipid and anti-DNA antibodies are largely separate groups of antibodies. On the basis of these studies, we suggest that there may be various groups of antiphospholipid antibodies in patients with SLE and other autoimmune disorders.
Autoantibodies↗
Affinity purified anti-cardiolipin and anti-DNA antibodies.
Recent studies have raised questions concerning the specificity of anticardiolipin antibodies and their relationship to anti-DNA antibodies, the lupus anticoagulant, the biological false positive test for syphilis, and reagin, the antibody detected in syphilis. In an attempt to answer some of these questions, 3 IgG and 2 IgM affinity purified anticardiolipin antibodies, as well as 3 affinity purified anti-DNA antibodies were studied. Affinity purified anti-cardiolipin antibodies showed high binding to negatively charged phospholipids but not to ssDNA by solid phase radioimmunoassay. On the other hand, affinity purified anti-DNA antibodies did not bind cardiolipin. Inhibition experiments showed that negatively charged phospholipids and VDRL liposomes inhibited the binding of anticardiolipin antibodies to phosphatidylserine, but ssDNA, alpha-glycerol phosphate and hyaluronic acid did not. Similar studies of sera from patients with high anticardiolipin antibody levels supported the results obtained with affinity purified anticardiolipin antibodies. These results suggest that anticardiolipin antibodies bind negatively charged phospholipids and there appears to be little crossreactivity with DNA or unrelated negatively charged polymers such as hyaluronic acid. Both the negatively charged phosphodiester group and glyceride portions of the phospholipid molecules appear important for their antigenicity. Four of the 5 affinity purified anti-cardiolipin antibodies had lupus anticoagulant activity providing further evidence to suggest that these 2 groups of antibodies have the same or very similar specificities. Studies of sera from 3 patients with syphilis showed that VDRL liposomes inhibited reagin activity to a greater extent than did cardiolipin. On the other hand, in patients with autoimmune disorders, cardiolipin inhibited anticardiolipin antibody activity to a greater extent than did VDRL liposomes.(ABSTRACT TRUNCATED AT 250 WORDS)
Antibodies↗
Anticardiolipin antibodies and lupus anticoagulant.
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Antibodies↗
Insulin-like growth factor II receptors. Molecular radius and molecular weight determination using quantitative polyacrylamide gel electrophoresis.
High resolution quantitative polyacrylamide gel electrophoresis was employed under nondenaturing conditions to calculate a molecular weight, Mr, for rat placental membrane receptors that bind insulin-like growth factor II (IGF-II). An n-octylglucoside-soluble extract of receptors that had been enriched 20-fold during Sephacryl S-300 gel chromatography and designated peak 1 (Perdue, J. F., Chan, J. K., Thibault, C., Radaj, P., Mills, B., and Daughaday, W. H. (1983) J. Biol. Chem. 258, 7800-7811) was incubated with 125I-IGF-II in the presence or absence of an excess of unlabeled IGF-II and electrophoresed in glass tubes containing highly cross-linked polyacrylamide gels at concentrations ranging from 5 to 12% (w/v). A specifically labeled peak of IGF-II binding activity was identified by freezing, slicing, and counting the gels. The proteins eluted from the region of the gel when cross-linked to 125I-IGF-II with disuccinimidyl suberate and electrophoresed in the presence of sodium dodecyl sulfate have the same molecular weight, Mr, as the previously described IGF-II receptor. From the slope of a plot of log of the relative mobility, RF, at each of 6 to 7 gel concentrations for the 125I-IGF-II-receptor and for each of seven standard proteins (Ferguson-Hedrick plot), a retardation coefficient, KR, was determined. Using a reference curve constructed from a plot of square root KR versus the molecular radius, R, of the standard proteins, the IGF-II receptor was estimated to have a R of 4.13 nm and a calculated Mr of 250,000. Thus, quantitative procedures that separate native proteins based on their size and charge have provided information which is in good agreement with the results of studies of the IGF-II-receptor by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and supports the premise that it is a monomeric single chained glycoprotein, constrained by intradisulfide bonds and with a mass of 250 kDa.
Animals↗
The biochemical characterization of detergent-solubilized insulin-like growth factor II receptors from rat placenta.
A membrane preparation, the R3, obtained by differential centrifugation of rat placental homogenates is enriched in receptors that bind insulin-like growth factor II (IGF-II) preferentially and with avidity (Daughaday, W.H., Mariz, I.K., and Trivedi, B. (1981) J. Clin. Endocrinol. Metab. 53, 282-288). When this preparation was incubated with 2% (w/v) octyl-beta-D-glucopyranoside for 60 min at 0-4 degrees C, 60% of the membrane protein was solubilized without loss of binding activity. The 125I-IGF-II binding properties of the detergent-solubilized receptors were found to be similar to those of the membrane-associated receptor. The rate constants for association, ka, and dissociation, kd, and equilibrium dissociation constant, KD, were 8.5 X 10(8) M-1 min-1, 7.5 X 10(-3) min-1, and 1.3 nM for the detergent-solubilized receptors and 5.3 X 10(8) M-1 min-1, 4.2 X 10(-3) min-1, and 0.6 nM for the membrane receptors. Gel chromatography on Sephacryl S-300 concentrated the solubilized receptors into a major peak of binding activity with a Stokes radius of 7.2 nm; a second peak of less specific binding had a Stokes radius of 4.3 nm. The receptors in the major peak bound 125I-IGF-II with a KD of 0.6 nM; the total binding capacity, Ro, was 21.6 pmol mg of protein-1 compared to 1.6 pmol mg of protein-1 for the membrane-associated receptor. Centrifugation of the receptors on 5-20% (w/v) gradients of sucrose in H2O or D2O disclosed a heterogeneous pattern of receptor distribution. When they were labeled with 125I-IGF-II prior to centrifugation, a major form of the receptor with a sedimentation constant, S20,w, of 9.9 X 10(13) s and other, possibly smaller, forms of the receptor were observed. However, only the 9.9 s20,w form of the receptor was observed if it was labeled with 125I-IGF-II subsequent to centrifugation. Based on these hydrodynamic measurements and a partial specific volume of 0.72 cm3/g, the IGF-II receptor was calculated to have a Mr of 290,000 and frictional ratio, f/fo, of 1.6. This value for the Mr is similar to the mass of 220,000 or 250,000 Dal determined by cross-linking 125I-IGF-II to the membrane- or detergent-solubilized receptors with disuccimidyl suberate and separating the complex by electrophoresis in sodium dodecyl sulfate-containing polyacrylamide gels in the absence or presence of dithiothreitol, respectively.
Animals↗
An evaluation of peroxidase as a marker for estrogen action in normal mammary glands of mice.
The present studies were initiated to study peroxidase and its possible regulation by estrogen in normal mammary glands. The activity of peroxidase was measured biochemically using guaiacol as the substrate for oxidation. Significant levels of peroxidase activity were associated with the particulate fraction of mammary glands from virgin mice, pregnant mice, and mice undergoing lactational involution. However, during lactation there was no detectable level of peroxidase activity in the mammary glands. Although ovariectomy led to a decrease in mammary peroxidase, detailed studies using various hormonal manipulations revealed that mammary peroxidase was perhaps not a product of estrogen action alone, but might be the result of a complex hormonal control related to growth. Alternatively, a critical evaluation of all of the data obtained with mammary glands and a comparison of these data obtained with the uterus also suggest that the presence of peroxidase in mammary glands may be due to infiltration of eosinophils and macrophages in these tissues resulting from mast cell degranulation.
Animals↗
Transfer of resistance with syphilitic immune cells: lack of correlation with mitogenic activity.
Hamsters infected intradermally with Treponema pallidum Bosnia A develop extensive chronic skin lesions, usually accompanied by metastatic lesions involving the paws, lips, and anal region and by lymph nodes teeming with treponemes. Throughout the course of syphilitic infection, cells from the inguinal lymph nodes responded poorly to stimulation with suboptimal, optimal, or supraoptimal concentrations of concanavalin A, phytohemagglutinin P, or lipopolysaccharide. The response of syphilitic spleen cells was variable. Depression of lymphocyte reactivity to mitogens preceded clinical signs of infection and correlated well with the chronicity of syphilitic infection. When syphilitic hamsters were treated with a curative dose of penicillin, their mitogenic responses returned to normal or were slightly elevated. No correlation existed between mitogenic activity and the ability of lymphoid cells to induce an effective immune response when transferred to normal recipients. No significant differences in protection were detected among recipients of immune cells with or without activity to mitogens. These results demonstrate that lymphocyte transformation by mitogens in vitro is not a measure of effective treponemicidal activity and so may not be a valid indicator of the protective immune status of syphilitic animals.
Animals↗
Mitogenic responses of hamsters infected with Treponema pertenue Lack of correlation with passive transfer of resistance.
Infection of the CB/Ss Lak hamster with Treponema pertenue is characterised by chronic cutaneous lesions and lymph nodes teeming with treponemes. Throughout the course of infection lymph node and spleen cells responded poorly to the mitogens concanavalin A, phytohaemagglutinin, and lipopolysaccharide. This impairment preceded clinical signs of infection and correlated well with the chronicity of framboesial infection. High concentrations of antigen from T pertenue, but not from the non-pathogenic Treponema phagedenis, depressed the mitogenic response of normal lymphoid cells. After framboesial hamsters were treated with penicillin the mitogenic activities of their lymph node and spleen cells were similar to or slightly raised above those of controls. No significant differences were detected among recipients of framboesial immune cells with or without mitogenic activity. Recipients of immune lymph node and spleen cells from penicillin-treated or non-penicillin-treated animals had no cutaneous lesions 21 days after infection and had significantly lower lymph node weights and fewer treponemes per node than recipients of cells from normal penicillin-treated or non-penicillin-treated animals. Since lymphocyte transformation in vitro does not correlate with in-vivo treponemicidal activity, it is not a valid approach to assess the protective immune capacity of the framboesial host.
Animals↗
LSH hamster model of syphilitic infection and transfer of resistance with immune T cells.
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Animals↗
Pre-T chronic lymphocytic leukemia with common acute lymphoblastic leukemia antigen. A new immunologic variant.
Chronic lymphocytic leukemia (CLL) is a B cell disorder but occasionally may have the characteristics of a T cell and rarely as a dual T and B cell. A case of pre- T cell and rarely as a dual T and B cell. A case of pre-T CLL with common acute lymphoblastic leukemia antigens is presented. The markers Studies of the bone marrow lymphocytes were +HTLA, +cALL, +EAC, +Ia, -TdT, -E and peripheral blood lymphocytes were +HTLA, +Ia, -cAll, -EAC, -TdT, -E. The poor course of our patient suggests that more detail subtyping of CLL to identify similar subtype may provide additional prognostic information.
Antigens, Neoplasm↗
Influence of the virulence of Mycobacterium tuberculosis on protection induced by bacille Calmette-Guérin in guinea pigs.
The protective efficacy of two bacille Calmette-Guérin (BCG) vaccines was examined in guinea pigs infected by the respiratory route with strains of Mycobacterium tuberculosis differing in virulence. Virulence was defined as the degree of tissue damage (weight) of primary lesions excised from lungs of unvaccinated guinea pigs killed 28-42 days after infection. Groups of animals vaccinated with BCG-Copenhagen (strain no. 1331), a vaccine of high potency, or those vaccinated with BCG-Prague (strain no. 725), an experimental vaccine of low potency, and groups given placebo were challenged six weeks later with one of three challenge strains differing in virulence. Protection was assessed from the difference in the number of tubercle bacilli recovered from excised primary lung lesions or from primary lesion-free lung lobes of vaccinated vs. unvaccinated animals. The virulence of the challenge strain influenced the efficacy of BCG vaccination; however, the results of other studies with a laboratory strain were in general replicated.
Animals↗
Formation of nonspecific precipitants in sera by counterimmunoelectrophoresis.
Formation of nonspecific precipitants in sera in different kinds of agarose and batches of barbital buffer by routine counterimmunoelectrophoresis was observed. These nonspecific precipitants consistently locating at the cathodal side of the well upon counterimmunoelectrophoresis can lead to the incorrect interpretation that a specific antibody is present in the patient's serum against the antigens tested. This observation indicates the importance of including a negative control (patient's serum alone) with each individual sample tested by counterimmunoelectrophoresis for the detection of specific antibody to reduce false-positives.
Antibodies, Bacterial↗
Endemic syphilis: transfer of resistance to Treponema pallidum strain Bosnia A in hamsters with a cell suspension enriched in thymus-derived cells.
Direct evidence for involvement of thymus-derived (T) cells in host defense against syphilitic infection is presented. Irradiated, bone marrow-reconstituted hamsters receiving cells from hamsters immune to infection with Treponema pallidum strain Bosnia A had significantly lower weights and fewer treponemes per lymph node than animals that had received normal lymphoid cells or only normal bone marrow cells. Cell suspensions enriched in T cells from immune hamsters were obtained by sequential filtration of pooled spleen and lymph node cells through glass- and nylon-wool columns. The fractionated suspensions of cells responded poorly to stimulation by phytohemagglutinin, Escherichia coli lipopolysaccharide, and dextran sulfate, but responded relatively strongly to the T-cell mitogen, convanavalin A. After fractionation the proportion of cells susceptible to antithymocyte serum and complement increased significantly. These immune cell suspensions depleted of bone marrow-derived cells closely resembled unfractionated suspensions in their ability to confer resistance to challenge with T. pallidium.
Animals↗