Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The surface of dendritic cells from mouse spleen, thymus, and epidermis has been compared with a panel of monoclonal antibodies and the FACS. A method was first developed to isolate populations of large, adherent, thymic dendritic cells that were greater than 90% pure. These were released by collagenase digestion and separated from adherent macrophages after overnight culture. Enrichment was based on the facts that most macrophages remained plastic adherent and rosetted strongly with antibody-coated erythrocytes. As in spleen, thymic dendritic cells were stellate in shape, had abundant class I and II MHC products, lacked many standard macrophage and lymphocyte markers, and actively stimulated the mixed leukocyte reaction. Most spleen and thymic dendritic cells could be lysed by the 7D4 mAb, to the low-affinity IL-2 receptor, and complement but the levels of 7D4 by FACS were low and sometimes not above background. Differences among dendritic cells from different tissues were noted with other mAb. Adherent dendritic cells from thymus all expressed the J11d "B cell" antigen and the NL145 interdigitating cell marker, but lacked the 33D1 spleen dendritic cell antigen. Eighty to ninety percent of spleen dendritic cells were J11d-, NL145-, 33D1+ but the remainder expressed the J11d+, NL145+, 33D1- thymic phenotype. The latter phenotype also was identical to that of epidermal Langerhans' cells. We postulate that the major 33D1+ cell in spleen represents a migratory stage in which dendritic cells are moving from tissues to lymphoid organs.
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PMID:The cell surface of mouse dendritic cells: FACS analyses of dendritic cells from different tissues including thymus. 291 Apr 99

Equine immunoglobulin was detected along the glomerular basement membrane of three human homograft recipients who had been treated with equine anti-lymphocyte globulin. Anti-lymphocyte globulins, given these patients, were obtained by immunization of horses with lymphocytes from human spleens and/or lymph nodes and contained glomerular basement membrane-reactive antibodies. Quantitative paired-label isotope experiments (in rats) demonstrated that 30-170 mug/ml of kidney-fixing antibodies were present in these preparations. The anti-lymphocyte globulins formed a line of identity with a sheep anti-human glomerular basement serum when reacted against collagenase-solubilized human glomerular basement membrane in double diffusion in agar. The renal fixation of these antibodies was blocked by absorption with human glomerular basement membrane, but not by buffy-coat leukocytes, indicating that they were directed specifically toward antigens in the basement membrane and were not cross-reacting anti-lymphocyte antibodies. Anti-lymphocyte globulin preparations for human use were studied for glomerular basement membrane-reactive antibodies by a direct immunofluorescent assay in rats. Anti-lymphocyte globulin from 13 of 20 horses, and 7 of 10 serum pools from horses immunized with lymphocytes derived from solid lymphoid organs (spleen, thymus, lymph node, tonsil), contained glomerular basement membrane-reactive antibodies. Sera from 18 horses injected with thoracic duct cells or cultured lymphoblasts had no glomerular basement membrane-reactive antibodies. An equine anti-human thymus serum containing glomerular basement membrane-reactive antibodies, which produced fatal glomerulonephritis in monkeys, was shown to cause both immediate and delayed glomerular injury in monkeys after intravenous injection. The reaction of this antibody with glomerular basement membrane in vivo was associated with little complement deposition in spite of the fact that the antibody could fix complement. This lack of glomerular complement fixation resulted from almost complete in vivo decomplementation of the monkeys receiving this anti-lymphocyte globulin.
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PMID:Glomerular basement membrane--reactive antibody in anti-lymphocyte globulin. 499 86

Two different approaches were used to examine the role of B cells in the stimulation of syngeneic MLR. The relative inability of spleen and peritoneal exudate cells from B cell deficient mice, treated with anti-mu from birth, to serve as stimulator cells in SMLR was previously shown in SJL mice and confirmed in BALB/c mice in the present studies. Preincubation of cells from anti-mu treated mice with serum Ig does not enhance their ability to stimulate. Upon stimulation with normal spleen cells responses from anti-mu treated mouse T cells are not deficient. Responses of thymus cells from neonates and from adult cortisone-treated mice are also much higher when the splenic stimulator cells come from normal rather than from anti-mu treated mice. The deficiency of the stimulator cells from anti-mu treated mice is in the high density cell population as obtained after BSA gradient fractionation of collagenase treated lymph node or spleen fragments. Low density populations from anti-mu treated and normal mice stimulate equally well. Addition of exogenous IL-2 to the cultures enhances the syngeneic MLR to all stimulator populations and allows stimulation by spleen cells from anti-mu treated mice. It is concluded that, while B cells represent the major stimulator cell population in whole spleen cell suspensions, other accessory cells (dendritic cells?) are more efficient, possibly synergize with B cells by producing IL-1, but usually represent only a minor subpopulation. The other approach concerns the effectiveness of SMLR stimulation by several tissue culture, cloned B lymphoma cell lines, and by a transplantable BALB/c B lymphoma. Of the five stimulating lymphoma cell lines only one stimulates approximately as well in the absence as in the presence of polyethylene glycol. These latter cells (A20.1.11) can also stimulate T cell proliferation and IL-2 production in the absence of Ia+ accessory cells in the responding population and, therefore, either produce their own IL-1 or are able to bypass the requirement for this lymphokine.
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PMID:Role of B cells in the stimulation of syngeneic mixed lymphocyte responses. 624 30

By means of a biological collagenase assay the activity of this protease was examined in 12 invasive adenocarcinomas of the colon and compared to that in 10 normal thymus tissue biopsies. Collagenolytic activity at dimensions of 10(-3) units/mm diameter tissue could be revealed in all carcinomas, which significantly (p less than 0.001) surpassed the also regularly detectable activity in thymi. While 0-Phenantrolin and D-Penicillamin totally inhibited lysis of each sample, EDTA and normal human serum, remarkably inhibiting collagenase of normal thymus, only were able to reduce the lysis by cancer at 19 and 23% in the average leading to enzyme: inhibitor imbalance in malignancy. It can be suggested that collagenolysis displayed by adenocarcinomas is derived from the tumor itself, and is different from that of normal thymus--a rapidly proliferating organ--by means of enzymatic quantity and quality.
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PMID:[Collagenolytic activity of neoplastic and rapidly proliferating normal tissue]. 626 Nov 99

Collagenase preparations (a mixture of enzymes including collagenase, clostripain, and a casein-degrading protease) degraded the beta subunit (Mr = 95,000) of the purified insulin receptor into fragments of Mr less than 15,000, without degrading the alpha subunit. The resulting beta-digested insulin receptor preparations were found to bind insulin as well as control insulin receptor, as assessed by either cross-linking of 125I-insulin to the digested receptor or by separating insulin bound to receptor from free insulin by high performance liquid chromatography. Moreover, the beta-digested insulin receptor preparations were still precipitated by a monoclonal antibody directed against the insulin-binding site. In contrast, the beta-digested insulin receptor lacked protein kinase activity since it no longer phosphorylated either itself, or an exogenous substrate, calf thymus histone. These results support the identification of the beta subunit of the insulin receptor as a protein kinase.
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PMID:Preferential degradation of the beta subunit of purified insulin receptor. Effect on insulin binding and protein kinase activities of the receptor. 631 28

Fluorescent conjugates of hydroxyethyl (OEt) starch of Ficoll are selectively ingested and retained in vivo by spleen marginal-zone (MZ) and lymph node marginal-sinus macrophages of mice, whereas similar conjugates of type 3 pneumococcal capsular polysaccharide (SIII) are generally retained by macrophages (Kupffer cells, histiocytes, macrophages of spleen, lymph nodes, bone marrow and peritoneal cavity). MZ and other macrophages are readily identifiable by fluorescence after injection in vivo of OEt starch and SIII labeled with tetraethylrhodamine isothiocyanate and fluorescein isothiocyanate. Collagenase digestion was required for recovery of intact MZ macrophages from spleen in single cell suspensions and for maximum yields of other macrophages. MZ macrophages are larger and morphologically distinct from other macrophages, but resemble them in respect of EA, EAC receptors and acid phosphates and nonspecific esterase content and are equally radio-resistant. The appear normal in CBA/N nude and in beige mice. Freshly isolated MZ macrophages in suspension have adherent lymphocytes, dispersible by EDTA treatment, with B but not T cell markers. It is suggested that selective adherence to MZ macrophages is a factor in determining B cell traffic. MZ macrophages did not have demonstrable surface I-A or I-EC antigens. Only 4--8% of other spleen macrophages freshly isolated by collagenase treatment expressed I-A in the same preparation, whereas 35% of other cells (lymphocytes and blasts) reacted with monoclonal anti-I-A and anti-I-EC. After adherence to glass or plastic, 40% or more red-pulp, but not MZ macrophages, became I-A-positive. When taken from mice recently restimulated with sheep erythrocytes, half the red-pulp macrophages expressed I-A even before adherence. The relation of MZ to other macrophages is not known. However, their properties are consistent with the demonstrated ability of thymus-independent antigens selectively taken up by these cells to elicit long-lasting IgM antibody responses by direct interaction with B cells. The unexpected observation that only a small proportion of spleen macrophages freshly isolated from unstimulated mice had detectable surface I-A, but that this proportion was much increased after attachment to plastic, is discussed in relation to the possibility that macrophages do not express surface Ia antigens unless they have been stimulated.
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PMID:Different macrophage populations distinguished by means of fluorescent polysaccharides. Recognition and properties of marginal-zone macrophages. 694 Jul 55

Freshly prepared rat hepatocytes isolated by perfusion with collagenase were able to metabolize microM concentrations of dimethylnitrosamine to a methylating agent. The methylation of hepatocyte DNA in this system was complete within 2 hr, and after this time, the content of O6-methylguanine in the DNA declined, showing that the repair system for this product was active in the isolated hepatocytes. When extracellular calf thymus DNA was added to the incubated hepatocytes, this also became methylated. Methylation of this DNA was not due to cell lysis releasing activating enzymes into the medium, showing that the methylating species formed by the hepatocytes from dimethylnitrosamine is sufficiency stable to pass out of the cell in substantial amounts. These results support the possibility that alkylation of liver cells would not be confined to those cells metabolizing dimethylnitrosamine but could be extended to those cells which are in close proximity to the activating cells. These cells could include nonparenchymal cells which are known to be targets for the carcinogenic action of dimethylnitrosamine.
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PMID:Alkylation of intracellular and extracellular DNA by dimethylnitrosamine following activation by isolated rat hepatocytes. 726 Sep 9

Thymic adherent cells were isolated after their enrichment on density gradients. The predominant cell type found was the macrophage, as determined by morphology, surface receptors for Fc and C3, phagocytosis and esterase activity. There was, in addition, a minor fraction of cells with a distinctive dendritic morphology. These dendritic cells had surface properties similar to macrophages but limited phagocytic capacity. Approximately 50% of thymic adherent cells bear Ia antigens detected by immunofluorescence by using either A.TH anti-A.TL or monoclonal anti-I-A antibodies. These cells were also found to be an extremely effective antigen-presenting source for macrophage-depleted immune T cells, supporting the idea that the Ia antigens detected are of functional significance. Our data indicate that the macrophage is the predominant adherent cell type in general, and the principal Ia-bearing cell in particular, isolated by either physical disruption of the thymus or by collagenase dissociation of thymis stroma.
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PMID:IA antigens and antigen-presenting function of thymic macrophages. 735 86

We describe here the derivation of a rat monoclonal antibody (mAb) against mouse CD40 (designated 3/23), which stains 45-50% of spleen cells of adult mice, approximately 90% of which are B cells. Interestingly, some 5-10% of both CD4+ and CD8+ T cells in the spleens of (some, but not all) adult, unimmunized mice are also CD40+, whereas CD40+ cells were not detectable in the thymus, even following collagenase digestion. Some 35-40% of lymphoid cells in the bone marrow of adult mice are CD40+ and virtually all of these are B220+, and hence of the B cell lineage: triple-color flow cytometry showed that CD40 is expressed at low levels on some 30% of pre-B cells, at intermediate levels on 80% of immature B cells and on essentially all mature B cells in the bone marrow. These results, therefore, suggest that in the mouse CD40 is expressed relatively late during the process of B cell differentiation. The mAb induced marked up-regulation of major histocompatibility complex class II molecules, CD23 and B7.2 antigens on mature B cells. It also stimulated modest levels of DNA synthesis in mature B cells by itself: this was markedly enhanced by suboptimal concentrations of mitogenic (but not non-mitogenic) anti-mu and anti-delta mAb, and moderately enhanced by co-stimulation with interleukin-4. Hypercross-linking of CD40 (using biotinylated mAb and avidin) also enhanced the proliferative response to anti-CD40.
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PMID:Properties of mouse CD40: cellular distribution of CD40 and B cell activation by monoclonal anti-mouse CD40 antibodies. 751 98

Dendritic cells (DC) from human and mouse thymus were compared. DC from both sources were isolated by digestion with collagenase, disruption of cellular complexes with a chelating agent, selection of light density cells, immunomagnetic bead depletion of other cell types (without depletion with anti-CD4 or anti-CD8) and finally sorting for cells expressing high levels of class II MHC. Yields of DC from human and mouse thymus were comparable (around 1 DC/10(3) thymocytes), they displayed similar DC morphology, and both showed strong expression of CD11c. DC from the human thymus all expressed very high levels of CD4 but low levels of CD8. In contrast, DC from the mouse thymus expressed high levels of CD8 but only low levels of CD4. Human thymic DC were also substantially larger than mouse thymic DC. The biological significance of CD4 and CD8 expression by DC is discussed in view of this major species difference and the possibility that human thymic DC may be targets for HIV infection.
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PMID:CD4 and CD8 expression by human and mouse thymic dendritic cells. 808 77


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