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11.
The C-C chemokine RANTES, a T lymphocyte chemoattractant, is considered an important mediator of inflammation, allergy, and host defense against HIV-1 infection. In this study, we investigated the modulation of binding of RANTES to T lymphocytes. Human peripheral blood CD3+ T cells, when freshly isolated from buffy-coat blood, expressed a considerable number of high-affinity binding sites for RANTES. These cells also showed significant chemotactic migration in response to RANTES in vitro. After 6–15 h incubation at 37°C, the binding of RANTES, but not of macrophage inflammatory protein-1α (MIP-1α) or of monocyte chemotactic protein-3 (MCP-3), consistently increased. Scatchard analyses indicated that the number of binding sites for RANTES increased about threefold by 15 h without any change in the affinity. The increase in RANTES binding was no longer detected by 24 h. This increase in the specific binding was mainly attributable to CD4+ T cells and was not associated with increased chemotactic activity of these cells in response to RANTES. Incubation with anti-CD3 antibody for 15 h markedly reduced the binding capability of T cells for RANTES and was associated with decreased chemotactic activity. On the other hand, when T cells were incubated with interleukin-2 (IL-2) for 1 week, the specific binding for all three C-C chemokines, RANTES, MIP-1α, and MCP-3 was markedly increased in comparison to cells cultured in the absence of IL-2. These results suggest that the expression of binding sites on T cells for RANTES is differentially modulated, indicating the existence of novel receptors for RANTES that do not bind MIP-1α.  相似文献   
12.
Antibodies to dsDNA are characteristically present in serum from patients with systemic lupus erythematosus (SLE), and have been shown to have the capacity to react with various molecules bearing repeating negative charges. After a number of polymeric or monomeric molecules with differently charged groups and hydrophobic molecules had been coupled covalently as ligands on cellulose gel, the adsorption capacities of the ligands for anti-dsDNA antibodies were evaluated. It was found that gels coupled with polyanionic dextran sulphate (DXS) and polyacrylic acid (PA) and monoanionic sulphanilic acid (SA) absorbed anti-dsDNA antibodies effectively. DXS gel also adsorbed antibodies to ssDNA and heparan sulphate, antigens with repeating negatively charged moieties, while no ligand was able to adsorb anti-nRNP antibodies. The finding that DXS gels adsorbed anti-dsDNA antibody in proportion to their charge density, and that the interaction between anti-dsDNA and DXS gel is broken readily by an increase in ionic strength, indicated that the binding is ionic in nature. Moreover, virtually all F(ab')2 anti-dsDNA became adsorbed onto the DXS gels, suggesting that the binding occurred via specific antigen-binding sites on the antibody molecule. Binding of these polyanion-binding autoantibodies with anionic sites in the glomerular basement membrane may therefore cause the tissue damage observed in SLE.  相似文献   
13.
14.
The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%.  相似文献   
15.
The aim of this study was to locate in male pigs the sensory and autonomic ganglia innervating the retractor penis muscle (RPM), which was taken as an experimental model of the genital smooth musculature. The retrograde neuronal tracers horseradish peroxidase (HRP), Fast Blue (FB), and diamidino yellow (DY) were injected into the bulbopenile portion of the left RPM. The tracers highlighted a different affinity for the neuronal structures, although labelled cells supplying the RPM were generally found in bilateral dorsal root ganglia (DRGs, S1-S3), in bilateral paravertebral ganglia (PaGs, L2-S3), and in the left and right caudal mesenteric ganglia (CMGs). The mean number of labelled FB cells was 795 (range, 645-952) in DRGs, 16046.25 (range, 10226-18742) in PaGs, and 635.25 (range, 333-786) in CMGs. The mean diameter of pseudounipolar DRG cells was 60-75 microm, while the multipolar neurons of PaGs and CMGs had dimensions varying between 20-50 microm and 20-30 microm, respectively.  相似文献   
16.
An immunohistochemical analysis of the cat central nervous system revealed that a monoclonal antibody which recognizes a soluble cytosolic protein, R2D5, bound two regions in a prominent spatial gradient. In the medial and lateral superior olivary nuclei of the brainstem, R2D5 immunoreactivity appeared as a gradient across a population of topographically ordered principal neurons. The spatial gradient corresponded to the tonotopic organization in the superior olivary nuclei: i.e., R2D5 immunoreactivity tended to occur more frequently and intensely in low-frequency neurons than in high-frequency neurons. Granule cells in the hippocampal dentate gyrus also had a pronounced spatial gradient in R2D5 immunoreactivity expression, and this gradient corresponded to the septotemporal axis of the hippocampus. Granule cells of the temporal (ventral) portions of the hippocampus were labeled intensely with R2D5 antibody, while those located in progressively more septal (dorsal) portions had gradually less immunoreactivity. These results suggest that in both the superior olivary nuclei and the hippocampal dentate gyrus, neurons differ in intrinsic properties by their position along specific axes. They suggest also that the hippocampus has an intrinsic functional organization related to the spatial gradient along its septotemporal axis.  相似文献   
17.
Zusammenfassung Ein 2 1/2 Stunden lang bei 45o erhitzter, nicht vollständig abgetöteter Pneumokokkenimpfstoff hatte schlechte immunisierende Wirkung.Ein anderer Pneumokokkenimpfstoff, der ebenfalls 2 1/2 Stunden auf 45o erhitzt, dabei aber vollständig abgetötet und dann nachträglich noch 1/2 Stunde auf 56o erhitzt war, war von guter Schutzwirkung.Hiernach sind durch schonende Abtötung bei niedrigen Temperaturen gewonnene Pneumokokken-Impfstoffe zum mindesten in ihrer Wirkung unzuverlässig und daher für die Praxis zu widerraten.Bei 100o 10 Minuten bis 4 Stunden lang erhitzte Pneumokokken stets einen guten Impfstoff.14 Tage lang täglich 1 Stunde auf 100o erhitzte Pneumokokken ergaben nur schlechte immunisierende Wirkung.Bei längerer Züchtung typischer Pneumokokkenstämme bei 39o wurden verschiedenartige Veränderungen beobachtet, darunter Virulenzabschwächung. Derart avirulente Pneumokokken ergaben auch lebend meist schlechten Immunisierungserfold, doch kommen Ausnahmen vor.Ein solcher vollkommen avirulenter, aber noch gallelöslicher Pneumokokkus wirkte sowohl lebend als auch nach Abtötung bei 100o gut antigen.  相似文献   
18.
Dendritic cells (DC) are professional antigen-presenting cells in the immune system. Gene transduction of DC with tumor-associated antigen (TAA) or other genes that enhance the immune reaction has been considered theoretically useful for DC-based immunotherapy. However, gene transduction of DC generated from human peripheral blood monocytes has been difficult due to its low efficiency, even when adenoviral vector was used at high multiplicity of infection (MOI). In the present study, we examined the effect of centrifugal force to enhance efficiency of adenovirus-mediated gene transduction into human monocyte-derived DC at various rotor speeds at various temperatures for various times. We judged the transduction efficiency using enhanced green fluorescence protein (EGFP)-expressing adenoviral vector, and the best condition for centrifugal transduction was determined as 2000 x g at 37 degrees C for 2 h at an MOI of 10 or greater. At an MOI of 50 without centrifugation, the gene transduction efficiency was about 66% and mean fluorescence intensity (MFI) of EGFP expression was about 150 (at 37 degrees C for 2 h). With centrifugal transduction (2000 x g at an MOI of 50 at 37 degrees C for 2 h), 86% or more DC were gene-modified, and especially, MFI of EGFP expression was highly enhanced (MFI: about 3100 or greater). Centrifugally gene-transduced DC were not damaged and were thoroughly functional as measured by mixed lymphocyte reaction (MLR). The centrifugal method was also applicable to human monocytes and K562 cells. The centrifugal transduction method with adenoviral vector might be helpful for the generation of gene-modified DC.  相似文献   
19.
A new metabolite of the diuretic drug bumetanide, the 4-[(4-hydroxy)-phenoxy] analog (7), was identified in incubation mixtures of rat liver microsomes. Phenobarbital and clofibrate pretreatment to induce microsomal enzymes changed the relative amounts of the six metabolites formed. Compound 7was the most prevalent metabolite after clofibrate pretreatment.  相似文献   
20.
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