Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The changes occurring in the hematopoietic extracellular matrix in an experimental myeloproliferative syndrome were explored by comparing the glycosaminoglycan (GAG) composition of normal mouse spleens and spleens infected with myeloproliferative sarcoma virus (MPSV). Large quantities of hyaluronate and of sulfated GAGs accumulated in the extracellular matrix of infected spleens, as shown by histoimmunoassay and alcian blue staining, respectively. The splenic GAGs were either labeled with 35S-sulfate injected in vivo or unlabeled. The spleens were fractionated to separate hematopoietic cells from the stromal component containing extracellular matrix material and fibroblasts, and the GAGs were extracted from each fraction. Specific degradative treatments and electrophoresis indicated that sulfated GAGs were mostly chondroitin sulfate and heparan sulfate. Three hours after in vivo injection of 35S-sulfate, the amount of 35S-GAGs was increased approximately fivefold per mg stromal proteins. The bulk of these 35S-GAGs (70%) was recovered in the stromal fraction. The higher amount of sulfated GAGs in leukemic spleen was due both to the presence of more producer cells (infected fibroblasts and hematopoietic cells) and to a stimulation of GAG synthesis per cell, as evidenced 35S-labeling in in vitro experiments. Chondroitin sulfate was the main sulfated GAG present in the culture medium of both hematopoietic and fibroblastic cells and in the pericellular material released by trypsin from fibroblastic cells. High amounts of chondroitin sulfate, which has a possible role in the detachment of hematopoietic cells from the stromal cells, may favour the release of hematopoietic cells from the spleen into the peripheral blood. Heparan sulfate was produced by fibroblastic cells and it was principally present in their pericellular material. Considering the capacity of heparan sulfate to retain cytokines, as demonstrated by others in vitro, large amounts of heparan sulfate may result in the retention of large amounts of the cytokines, which production is enhanced in the infected spleen. This phenomenon may contribute to promote the hematopoietic stem cell proliferation characteristic of the MPSV-induced myeloproliferative disease.
Leukemia 1992 Oct
PMID:Increased synthesis of extracellular spleen glycosaminoglycans in an experimental myeloproliferative syndrome. 132 75

The glycosphingolipids GD3, GM3, and alpha 2, 3-sialosylparagloboside (SPG) are major gangliosides of lymphoid leukemia cells. The reactivity of two monoclonal anti-ganglioside antibodies, an anti-GD3 (R24) and an antibody cross-reactive to GM3 and SPG (M2590), to blasts of patients with T-cell acute lymphoblastic leukemia (ALL) and B-cell precursor ALL (pre-B-ALL), were compared using indirect immunofluorescence and flow cytometry. Results from 23 patients with T-ALL and eight with pre-B-ALL yielded four subclasses of T-ALL and two subclasses of pre-B-ALL. Blasts from most of the patients with T-ALL were R24+M2590- whereas most of the patients with pre-B-ALL were R24-M2590-. Seven of 23 patients with T-ALL had ganglioside immunophenotypes similar to that of pre-B-ALL, i.e. R24-M2590- or R24-M2590+. These subclasses could not be further characterized by additional cell surface immunophenotypic markers or by gene (immunoglobulin and T-cell receptor) rearrangement analysis. The ratio R24/M2590 was less than 1.0 in all patients with pre-B-ALL, and was greater than 1.0 in all patients with T-ALL who were R24 positive, but was not useful in characterizing the double negative T-ALL subclass. To assess whether cryptogenicity of gangliosides due to cell surface protein could account for the low binding of either R24 or M2590, blasts were treated with trypsin before antibody analysis. Whereas the binding of R24 was unchanged after trypsin treatment, binding of M2590 was increased in a number of samples, particularly in those samples which were originally M2590-positive. The results show that comparative staining of T-ALL and pre-B-ALL cells with both anti-GD3 and anti-GM3/SPG antibodies results in a further subclassification of ALL and provides a quantitative assessment of the expression of tumor-associated gangliosides on the blasts of this disease.
Leukemia 1991 Dec
PMID:Immunoreactivity of leukemic lymphoblasts of T-cell and B-cell precursor origin with monoclonal anti-GD3 and anti-GM3 antibodies. 177 57

The effect of large granular lymphocyte leukemia on B lymphocyte function was studied by determining the number of plaques formed in an in vitro hemolytic plaque assay. Leukemia cells inhibited plaque formation by normal splenic lymphocytes in a logarithmic, dose-dependent manner. At the highest leukemia cell concentrations, spleen cell suspensions made 50% fewer plaques. Plaque forming responses were very sensitive to duration of preincubation time in all assays. The number of plaques formed decreased markedly if incubated 2 hr before the assay was performed. Incubation of the cells at 56 degrees C for 8 min did not alter the inhibitory activity but pretreatment with 0.01% trypsin did. Supernatant fluids from leukemia cell suspensions did not inhibit plaque formation. These data suggest that diffuse infiltration of lymphoid tissues by leukemia cells may interfere with some normal lymphocyte functions. Although leukemia cells inhibited splenic B lymphocyte function, leukemic rats did not have hypogammaglobulinemia.
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PMID:Inhibition of in vitro plaque formation by large granular lymphocyte leukemia cells from F344 rats. 196 81

We studied the cells from three selected patients with Ph-chromosome-negative chronic myeloid leukemia (CML) by Southern blotting, polymerase chain reaction, and in situ hybridization of informative probes to metaphase chromosomes. All three patients had rearrangement of M-BCR sequences in the BCR gene and expression of one or other of the mRNA species characteristic of Ph-positive CML. Leukemic metaphases studied after trypsin-Giemsa banding were indistinguishable from normal. The ABL probe localized both to chromosome 9 and 22 in each case. A probe containing 3' M-BCR sequences localized only to chromosome 22, and not to chromosome 9 as would be expected in Ph-positive CML. Two new probes that recognize different polymorphic regions distal to the ABL gene on chromosome 9 in normal subjects localized exclusively to chromosome 9 in two patients and to both chromosomes 9 and 22 in one patient. These results show that Ph-negative CML with BCR rearrangement is associated with insertion of a variable quantity of chromosome 9 derived material into chromosome 22q11; there is no evidence for reciprocal translocation of material from chromosome 22 to chromosome 9.
Leukemia 1990 Apr
PMID:Interstitial insertion of varying amounts of ABL-containing genetic material into chromosome 22 in Ph-negative CML. 216 19

We examined the distribution of actin in isolated nuclear matrices from mouse leukemia L5178Y cells using an anti-actin antibody and protein A-conjugated colloidal gold particles. Before immunogold staining, we partially digested the surface lamina of the nuclear matrix with trypsin (Nakayasu and Ueda, Exp. Cell Res. 143, 55-62, 1983) to allow penetration of the gold particles into the nuclear matrix. Trypsin digestion slightly modified the internal structure of the nuclear matrix, but did not affect the actin content in the nuclear matrix nor the reactivity of actin with the antibody. Many colloidal gold particles were present along fibrogranular structures in the nuclear matrix. The results reported here confirm the existence of actin in the interior of the nuclear matrices of L5178Y cells.
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PMID:Ultrastructural localization of actin in nuclear matrices from mouse leukemia L5178Y cells. 241 12

A factor that stimulates the incorporation of 75Selenomethionine into the newly formed platelets of recipient mice (thrombopoietin, TPO) has been partially purified from the plasma of thrombocytopenic patients. The activity was precipitated at 60-80% ammonium sulfate saturation and further purified with hydrophobic interaction chromatography. Thrombopoietin was retained by concanavalin-A-Sepharose. Using HPLC size-exclusion chromatography, an approximate molecular weight of 40,000 dalton was calculated. The overall purification factor was about 2,100-fold. TPO was stable in a pH range from 5 to 9 and was heat-sensitive, and the biological activity was destroyed by trypsin treatment and by dithiothreitol. The partially purified molecule did not stimulate the proliferation of megakaryocyte progenitors in vitro and had no effect on the growth of erythroid or granulocyte-macrophage colonies; when administered in-vivo, TPO significantly affected the mean platelet volume and increased the number of small acetylcholinesterase cells in the bone marrow. TPO appears to be specific for the megakaryocytic lineage and active on the postmitotic compartment of megakaryocytes.
Leukemia 1988 Apr
PMID:Partial purification and biochemical characterization of human plasma thrombopoietin. 336 51

Leukemia associated inhibitor, LAI, reversibly inhibits DNA synthesis in normal human granulocyte-macrophage colony-forming units (CFU-GM). LAI is produced by myeloid leukemia cells, a subpopulation of normal nonadherent low-density mononuclear cells in peripheral blood and bone marrow, as well as by the human promyelocytic cell line HL-60. Normal low-density marrow cell absorbed LAI at 37 degrees C from HL-60 cell-conditioned medium. When normal marrow cells were treated with trypsin or chymotrypsin they lost their capacity to absorb LAI and also became insensitive to the inhibitory effect of LAI. These observations were taken as circumstantial evidence for the existence of a trypsin-sensitive LAI receptor on normal marrow cells, including CFU-GM. Glucocorticoid steroids (hydrocortisone, prednisolone, and dexamethasone) inhibited LAI production by acute myeloid leukemia (AML) cells, normal LAI-producing cells, and HL-60 cells. The fact that prostaglandin E1 (PGE) totally inhibited LAI production by normal cells and that indomethacin abrogated the inhibitory effect of adherent cells on LAI production suggested a role for adherent monocytic cells and PGE in the regulation of LAI production.
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PMID:Modulation of the production of leukemia associated inhibitor (LAI) and its interaction with granulocyte-macrophage colony-forming cells. 350 70

Nuclear matrix prepared from mouse leukemia L5178Y cells contained not only the two common actin isomers, beta and gamma actins, but also two additional acidic species of actin (pI 5.1 and 5.3). An anti-actin antibody recognized these acidic species as well as beta and gamma actins on a nitrocellulose filter following western blotting of two-dimensional electrophoresis. These acidic species were co-purified with beta and gamma actins using DNase I-Sepharose affinity chromatography on the nuclear matrix. Limited digestion of the acidic actin with protease V8 or trypsin gave very similar peptide fragments as did digestion of beta and gamma actins. These acidic actins were found to be distributed in the nuclear fraction, but were scarcely detectable in the cytoplasmic fraction. One of the acidic actins (pI 5.3) was found in all subnuclear fractions (DNase extract, high-salt extract and nuclear matrix), while the other species, the most acidic actin (pI 5.1), was localized predominantly in the nuclear matrix.
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PMID:Preferential association of acidic actin with nuclei and nuclear matrix from mouse leukemia L5178Y cells. 351 45

Leukemia-growth-promoting factor (LGPF) as we previously reported stimulates the growth of a murine leukemia subline (L17R) extensively. LGPF was isolated and 10(4) fold purified from calf thymuses by a combination of ammonium sulfate precipitation, Sephadex G-100 chromatography, hydroxylapatite chromatography, and Mono S-fast protein liquid chromatography (Mono S-FPLC). The mol. wt of LGPF was estimated to be approximately 25,000 a.m.u. from the elution pattern of Sephadex G-100 chromatography. The activity had high affinity for Mono S beads which are cation exchangers. Mono S fractions of LGPF are effective at a low concentration of 5 ng/ml. The activity was inactivated by heat (56 degrees C, 30 min), 1 mg/ml trypsin (37 degrees C, 1h), and 50 mM dithiothreitol (20 degrees C, 1h). The growth L17R leukemia cells are not only stimulated by LGPF, but also by pituitary and brain fibroblast growth factor (FGF). These data strongly suggest that LGPF is a heat sensitive cationic protein(s) acting as a member of FGF family.
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PMID:Isolation and characteristics of a leukemia-growth-promoting factor from calf thymus. 386 13

A lymphokine inhibitory for cellular DNA synthesis (termed STIF) was isolated from the culture supernatants of concanavalin A (Con A)-stimulated SD rat spleen cells. STIF inhibited the DNA synthesis of mouse bone marrow cells as well as mouse leukemia cells. STIF has an apparent m.w. of 45,000 to 50,000 and is separable from IL 2, m.w. 20,000 to 25,000, by Sephacryl S-200 gel filtration, but not from immune interferon (IFN) having the same m.w. as STIF. Con A-Sepharose chromatography of the fraction containing STIF and IFN could separate these lymphokines into Con A-unbound and Con A-bound fractions, respectively. Further fractionation of the STIF fraction by DEAE-Sephadex A-50 or Mono Q-FPLC anion exchange chromatography indicated that the STIF fraction contained two components of STIF activity, both showing the same pI value (5.1 to 5.6) on flat-bed isoelectric focusing. STIF was characterized as a sugar-free lymphokine of trypsin-sensitive protein nature.
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PMID:Stimulated rat T cell-derived inhibitory factor for cellular DNA synthesis (STIF). I. Isolation and characterization. 391 68


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