Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The physicochemical properties of nuclear and cytosolic glucocorticoid-binding components from corticoid-sensitive (CS) and corticoid-resistant (CR) mouse lymphoma P1798 cells have been compared. Nuclei or cytosol fractions were prepared from lymphocytes that had been labeled at 37 or 4 degrees, respectively, with 30 nM [3H]triamcinolone acetonide ([3H]TA). [3H]TA was extracted with 0.6 M KCl, 10 mM spermidine, or 4.5 mM MgCl2 from CS nuclei and with 0.6 M KCl or 10 mM spermidine from CR nuclei. As reported previously, nuclear-associated [3H]TA in CR cells was resistant to extraction with mM concentrations of MgCl2. Loss of bound steroid during extraction with 0.6 M KCl was minimized by including the chymotrypsin inhibitor, carbobenzoxy-L-phenylalanine, in the extraction buffer. The inhibitor was not required during extraction with spermidine or MgCl2. Nuclear and cytosolic extracts were examined by analytical agarose gel filtration and glycerol density gradient centrifugation under high salt (0.6 M KCl) conditions. The glucocorticoid-binding component in KCl, spermidine, and MgCl2 extracts from CS nuclei was considerably larger and more asymmetrical [Stokes radius, 57 to 59 A; sedimentation coefficient, 3.64 to 3.70S; molecular weight, 90,000 daltons; frictional ratio, 1.8; axial ratio (prolate ellipsoid), 15] than the [3H]TA-macromolecular complex in KCl and spermidine extracts from CR nuclei[Stokes radius, 29 A; sedimentation coefficient, 3.23 to 3.30S; molecular weight, 40,000 daltons; frictional ratio, 1.25; axial ratio (prolate ellipsoid), 5]. Control experiments showed that the smaller size of the glucocorticoid-binding component in CR nuclei was probably not due to cleavage of a larger, CS-like complex during the extraction procedure. The larger size of the CS [3H]TA complex did not appear to result from aggregation of s a smaller species. No difference in physicochemical parameters of the binding component was observed if cells were labeled with [3H]dexamethasone instead of [3H]TA. However, [3H]dexamethasone complexes were less stable than those formed with [3H]TA as indicated by considerable dissociation of [3H]dexamethasone during gel filtration and gradient centrifugation. This may be due to the 3- to 5-fold lower relative binding affinity of [3H]dexamethasone. Analysis of [3H]TA-labeled cytosol by gel filtration and gradient centrifugation revealed the presence of a single binding component with physicochemical properties similar to those of nuclear [3H]TA complexes from the same strain of tumor. These results suggest that previously described differences in extractability of nuclear-associated [3H]TA between the CS and CR strains of mouse lymphoma P1798 and the lack of response of CR P1798 to glucocorticoid administration may be due, at least in part, to the presence of an altered glucocorticoid-binding component in the resistant tumor cells.
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PMID:Physicochemical differences between glucocorticoid-binding components from the corticoid-sensitive and -resistant strains of mouse lymphoma P1798. 47 39

Coculture of purified murine T cells with anti-CD3 monoclonal antibody (145-2C11) results in the induction of nonspecific cytotoxic T lymphocytes (CTL) with MHC-unrestricted cytolytic activity against a range of tumor targets. Serine proteases associated with effector cell granules are among the molecules postulated to play a role in cell-mediated cytolysis. The present study examines the ability of exogenous serine protease substrates to inhibit anti-CD3-activated cytotoxic T (ACT) cell-mediated killing of P815 mastocytoma and YAC1.2 lymphoma target cells. The chymotrypsin substrate N-acetyl-L-tyrosine ethyl ester (ATEE) was found to significantly inhibit ACT cell-mediated cytolysis. In contrast, the trypsin substrate N-benzoyl-L-arginine ethyl ester (BAEE) had little, if any, effect on ACT cell-mediated cytolysis. These effects were observed with both target cell populations. Conjugate inhibition studies performed with ATEE indicated that a chymotrypsin-like serine protease is involved in a postbinding event during cytolysis. Pretreatment of either target or effector cells with ATEE prior to cytolytic assay revealed that the chymotrypsin-like serine protease involved in cytotoxicity is of effector cell origin. Northern blot analysis of total RNA extracted from ACT cells revealed the presence of transcripts coding for CCP1 and CCP2 serine proteases known to be involved in antigen-specific CTL function, but little or no expression of the HF serine protease which has also been implicated in antigen-specific CTL killing. CCP2 exhibits chymotrypsin-like activity while HF displays trypsin-like activity. On the other hand, the CCP1 gene product has protease activity which resembles neither chymase nor tryptase activities. Thus, the level of mRNA expression for these serine proteases is consistent with our earlier observations, using the serine protease substrates, that a chymotrypsin-like serine protease but not a trypsin-like serine protease is involved in ACT cell-mediated cytolysis. "Lymphocyte panning" of ACT cells revealed abundant CCP1 and moderate CCP2 mRNA expression in CD4- and CD8+ anti-CD3-activated T cells with strong tumoricidal activity. CD8- anti-CD3-activated T cells with moderate cytolytic activity also expressed substantial levels of CCP1 and CCP2 mRNA, suggesting that both CD4- CD8- and CD4- CD8+ ACT cells participate in killing tumor targets. In contrast, CD4+ anti-CD3-activated T cells lacked both cytolytic activity and significant CCP1 and CCP2 mRNA expression. These findings are consistent with the involvement of chymotrypsin-like, as well as other, serine proteases in CTL-mediated lysis.
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PMID:Expression and utilization of chymotrypsin-like but not trypsin-like serine protease enzymes by nonspecific T killer cells activated by anti-CD3 monoclonal antibody. 153 39

We examined an antibody against Ki-1 antigen in 161 cases of malignant lymphoma, four of histiocytic sarcoma, and six of nonspecific lymphadenitis, using monoclonal antibody Ki-1, which is known to react selectively with activated lymphocytes, Reed-Sternberg cells, and Hodgkin's cells. Among them, 12 cases of malignant lymphoma demonstrated a diffuse positive cell membrane and/or cytoplasmic reaction of tumor cells and were categorized as Ki-1-positive lymphoma. Nine of these cases exhibited large cells with indented nuclei, distinct nucleoli, and abundant basophilic or amphophilic cytoplasm. Of the remaining three cases, two were of medium-sized and one of small-cell type. Immunologically, the 12 cases of malignant lymphoma demonstrated T-helper/inducer phenotype in six cases, B-cell in two case, and non-T, non-B in four cases. Tac and HLADR were positive in 9/12 and 4/5, respectively, and markers for histiocytes (lysozyme, alpha-1 anti-chymotrypsin, and OK-M1) were usually negative. Clinically, T-cell Ki-1-positive lymphoma was most likely to occur in the elderly, at extranodal sites, and had a rather poor prognosis (mean survival 35.5 months) as compared with B-cell and non-T, non-B lymphoma (7-52 months survival).
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PMID:Clinicopathological study of Ki-1-positive lymphomas. 260 19

A comparative study of large cell lymphoma (LCL) (ten B and ten T), Hodgkin's disease (15 cases), and true histiocytic lymphoma (two cases) was undertaken, using formalin-fixed paraffin-embedded tissue sections, a panel of eight antibodies, and one lectin to determine if any particular antibody or immunologic profile could reliably distinguish between these entities. The antibodies used were against Leu-M1, alpha-1-anti-chymotrypsin (alpha-ACT), alpha-anti-trypsin (alpha-AT), lysozyme, kappa, lambda, leukocyte common antigen (LCA), and S-100 protein. The lectin used was peanut agglutinin (PNA). Although Leu-M1 staining was positive in 11 of 15 cases (73%) of Hodgkin's disease, it was also positive in 4 of 10 cases (40%) of T-cell lymphoma, 2 of 10 cases (20%) of B-cell lymphoma, and 1 of 2 cases (50%) of true histiocytic lymphoma. Peanut-agglutinin staining results were similar to Leu-M1. The only staining profile that emerged was the presence of Leu-M1, PNA-, alpha-ACT, and alpha-AT staining in Reed-Sternberg (RS) cells in 11 of 15 cases of Hodgkin's disease. Leu-M1 and its staining pattern is characteristic, but not entirely specific for RS cells, and it was not positive in at least 25% of the cases of Hodgkin's disease in formalin-fixed, paraffin-embedded tissues. The limitations of this antibody and others should be recognized.
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PMID:A comparative marker study of large cell lymphoma, Hodgkin's disease, and true histiocytic lymphoma in paraffin-embedded tissue. 294 20

Macrophages produced and/or released a chemoattractant(s) for neutrophils after having been treated for 2 hr with soluble products from two lymphoma cell lines. Culture supernatants of the EL-4 and Yac-1 cell lines, but not sarcoma l, Bc100, or the macrophagelike cell line P388d1, triggered the release of the chemoattractant. The macrophage-derived chemoattractant (MDC) was detectable within 2 hr following triggering and culture supernatants had maximal activity by 48 hr. The triggering of the macrophages to release the chemoattractant and the activity of the chemoattractant was not dependent upon any component of fetal bovine serum. Activation of complement was also not involved, since activated serum did not competitively inhibit the chemotactic activity of the macrophage-derived chemoattractant. The chemoattractant was macromolecular, stable to heating at 90 degrees C for 15 min, sensitive to pronase and chymotrypsin, and was affected by treatment with low pH.
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PMID:Release of a chemotactic monokine upon treatment with lymphocyte supernatants. 345 83

Histological material was studied in five unselected cases of intestinal large-cell non-Hodgkin's lymphoma, occurring in patients either with previously diagnosed coeliac disease, or with atrophic mucosa at the time of diagnosis. The morphological diagnosis in each case was centroblastic lymphoma: these tumours were composed of large cells with pale nuclei and prominent nucleoli. No phagocytosis was evident, but some cells showed considerable pleomorphism. Polykaryotic giant cells were infrequent. Immunohistochemical staining for lysozyme, alpha-1-anti-trypsin and alpha-1-anti-chymotrypsin failed to demonstrate any of these proteins in the tumour cells, although they were identified in accompanying reactive macrophages. There is thus no evidence for a histiocytic nature in these five cases. The tumours were immunoglobulin-negative. Again, polyclonal immunoglobulin could be demonstrated in reactive (plasma) cells in and near the tumour. The relevance of these immunological markers is discussed. We suggest that these tumours, and possibly some of those reported in a similar situation by other investigators, are in fact lymphocytic in origin. They are probably examples of centroblastic lymphoma, although T-cell lymphoma, rare in the gastrointestinal tract, cannot be ruled out by our immunohistological studies.
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PMID:Large-cell intestinal lymphoma occurring in coeliac disease: morphological and immunohistochemical features. 348 59

The relation of lymphoma cells to gliomesenchymal stroma within nervous tissue was studied by peroxidase-antiperoxidase immunostaining of formalin-fixed and paraffin-embedded surgical specimens for fibronectin (FN), factor VIII-related antigen and glial fibrillary acidic protein in 17 malignant non-Hodgkin lymphomas of the brain. For comparison, 9 non-Hodgkin lymphomas, 6 Hodgkin lymphomas, and 19 plasmacytomas of the spinal or cranial epidural spaces were studied with the same methods. Lymphoma cells were consistently negative for all markers. All lymphomas of the brain showed conspicuous concentric perivascular circles of immunoreactivity for FN in parts infiltrating brain tissue. Such structures are considered to derive from splitting of basal laminae of preexisting brain vessels; they were not seen in tumors of the epidural space. Cells with conspicuous FN content were found in brain as well as in epidural lymphomas. A monohistiocytic origin of those cells was confirmed by presence of monohistiocytic markers lysozyme and alpha-1-anti-chymotrypsin. Thus, additional immunostaining for FN seems to be useful for detecting monohistiocytes/macrophages in brain tumors.
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PMID:Development of stroma in malignant lymphomas of the brain compared with epidural lymphomas. An immunohistochemical study. 353 55

We have shown that cytosol samples from human leukemia cells frequently contain glucocorticoid receptor fragments that have a mol wt (Mr) of approximately 52,000. In the present study we demonstrate that the Mr approximately 52,000-receptor fragments are derived from intact glucocorticoid receptors (Mr approximately 97,000) by the action of a serine protease. Mr approximately 52,000-receptor fragments were present in cytosol from 24 of 52 leukemia cell samples. Only normal size glucocorticoid receptors were present in cytosol samples if diisopropylfluorophosphate (DFP), a potent inhibitor of serine proteases, was added to the hypotonic buffer used for cytosol preparation. Receptor proteolysis was not inhibited by hydrolyzed DFP, benzamidine, phenylmethylsulfonylfluoride, aprotinin, iodoacetamide, or mercuric chloride. The leukemia cell protease digests the receptor at a different site than chymotrypsin, which digests the intact receptor to produce a Mr approximately 40,000 receptor fragment. Receptor messenger RNA (mRNA) in S49 mouse lymphoma cells and in human leukemia cells was analyzed by Northern hybridization with a cDNA for the normal glucocorticoid receptor. Mutant S49 mouse lymphoma cells that have abnormally small glucocorticoid receptors (Mr approximately 48,000) make a 5.0-kilobase receptor transcript in addition to the normal size 6.5-kilobase receptor transcript. A normal size receptor transcript of 6.5 kilobases was present in all of the human leukemia cells whether or not Mr approximately 52,000-receptor fragments were present. Therefore, abnormalities of glucocorticoid receptor mRNA, which may give rise to the synthesis of foreshortened receptors in certain mutant mouse lymphoma cells, are apparently absent from human leukemia cells.
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PMID:Characterization of glucocorticoid receptors and glucocorticoid receptor mRNA in human leukemia cells: stabilization of the receptor by diisopropylfluorophosphate. 354 20

We characterized the glucocorticoid receptor fragments produced by neutrophil elastase and compared these receptor fragments to nuclear transfer increased (nti) mutant receptors. Neutrophil elastase and chymotrypsin digested [3H]dexamethasone 21-mesylate labeled receptors at different sites to produce 52 kDa and 42 kDa fragments respectively. Both the 52 kDa elastolytic receptor fragments and 42 kDa chymotryptic receptor fragments bound to DNA-cellulose and were immunoadsorbed by anti-glucocorticoid receptor monoclonal antibodies (BUGR2). More extensive digestion of labeled receptors by neutrophil elastase produced 29 kDa receptor fragments that did not bind to DNA-cellulose and did not react with BUGR2 antibodies. The size of nti mutant receptors from S49 mouse lymphoma cell variants is intermediate between that of the 52 kDa elastolytic receptor fragments and 42 kDa chymotryptic receptor fragments. The nti receptors bound to DNA-cellulose with the same affinity as the 52 kDa elastolytic receptor fragments. However, the nti receptors were not immunoadsorbed by BUGR2 antibodies and did not react with these antibodies on Western blot analysis of denatured cellular proteins. The results indicate that 52 kDa elastolytic receptor fragments, 42 kDa chymotryptic receptor fragments and nti mutant receptors correspond to the same region of the receptor molecule. The failure of nti receptors to react with BUGR2 antibodies suggests that the nti receptors may have an altered sequence compared to the corresponding region of normal receptors.
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PMID:Immunochemical comparison of mutant glucocorticoid receptors and wild type receptor fragments produced by neutrophil elastase and chymotrypsin. 365 Jun 2

Glucocorticoid receptors in wild type and mutant S49 mouse lymphoma cells were affinity labeled with [3H]dexamethasone 21-mesylate and analyzed directly by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight of receptors in cytosol from wild type cells and nuclear transfer decreased (nt-) mutants was 97,000 (97 kDa). The molecular weight of receptors in cytosol from nuclear transfer increased (nti) mutants was 48 kDa. The 97 kDa receptor in cytosol from wild type cells was digested by chymotrypsin to a 40 kDa steroid-binding receptor fragment but the 48 kDa receptor in cytosol from nti mutants was resistant to digestion by chymotrypsin. In addition to the 48 kDa receptor, cytosol from nti mutants contained 40 and 18 kDa receptor fragments. Cytosol from the nt- mutants also contained 18 kDa receptor fragments. The 40 and 18 kDa receptor fragments were present in multiple subclones of a nti mutant cell line. Formation of these receptor fragments was not prevented by protease inhibitors and was not increased by extended incubation of cytosol samples. Both 48 and 40 kDa forms of the receptor, but not the 18 kDa form, could be activated and bound by DNA-cellulose.
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PMID:Characterization of glucocorticoid receptors in S49 mouse lymphoma cells by affinity labeling with [3H]dexamethasone 21-mesylate. 382 Nov 8


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