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

---

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

Human erythrocytes, porcine and rat liver cells, porcine spleen lymphocytes and cultured human lymphoma cells (266 Bl) have been labelled with 125I by the lactoperoxidase-H2O2 method. Large amounts of radioactivity were released when the iodinated cells were incubated in different buffers, and the rate of the release varied considerably between the different cells. Incubation at a higher temperature increased the release rate, while metabolic inhibitors such as iodoacetamide, trasylol or sodium azide did not. When collagenase was used during the preparation of spleen lymphocytes, the rate of the radioactivity release was decreased about 50%. Several findings indicated that the released radioactivity originated from free iodide. When the labelled lymphocytes were treated with a nonionic detergent, Nonidet P-40, 90% of the total radioactivity was solubilized. Only 10-15% of the radioactivity was stably bound in macromolecular material. The remaining part, corresponding to the amount of radioactivity released during incubation, was shown to be free iodide. It is concluded that the significance of the 125I-label in living cells has to be studied in each case at the specific experimental conditions used. After the unspecifically trapped iodide is released--normally after about 2 h--the label is considered to be useful for studies with intact cells.
...
PMID:The significance of 125I as a tracer for lymphocytes, liver cells and erythrocytes after iodination by the lactoperoxidase-H2O2 technique. 78 77

Incubation at 37 degrees C of spleen cells from rats, immunized with Gross virus-induced lymphoma, on collagen gels coated with membrane extracts of lymphoma cells yielded two different cell populations. The non-adherent cells showed greatly diminished cytotocicity for lymphoma cells compared with unfractionated spleen cell suspensions, whilst the specifically adherent cells which were recovered after collagenase digestion of the gels, showed enrichment of cytotoxic activity.
...
PMID:Fractionation of cytotoxic cells from tumour-immune rats on derivatized collagen gels. 108 73

The relationship between signals generated via the sIgR complex of B lymphocytes and subsequent changes in gene expression is poorly understood at the molecular level. To illuminate mechanisms that may couple these events, we examined the expression and function of tetradecanoyl phorbol acetate-response element (TRE)-binding proteins (i.e., activator protein 1, (AP-1)) in the murine B lymphoma cell line BAL-17.7.1 (BAL-17), which models primary B lymphocyte responses in a number of respects. Cross-linking of sIgR led to substantial induction of nuclear AP-1, in BAL-17 B cells, that bound the TRE, as detected by electrophoretic mobility shift assay. The sIgR-induced TRE-binding activity consisted of both Jun and Fos proteins, on the basis of immunoreactivity of nucleoprotein complexes with specific antisera. In addition, immunoprecipitation with specific antisera showed that de novo synthesis of Jun-B and c-Jun proteins, accompanied by c-Fos, was stimulated after cross-linking of sIgR on BAL-17 B cells. Transient transfection of BAL-17 B cells with reporter gene constructs showed that B cell AP-1 failed to trans-activate the TRE-containing human collagenase gene promoter, for which activity is dependent upon functional expression of cellular c-Jun. In contrast, sIg-induced AP-1 trans-activated a HSV-tk promoter that contained three TRE; this pattern of gene expression is consistent with the presence of functional Jun-B-containing AP-1 in B lymphocytes. These results are the first to attribute a functional role to sIgR-mediated AP-1 in B lymphoid cells and suggest that AP-1 functions to couple the sIgR complex to changes in nuclear gene expression.
...
PMID:Surface Ig receptor-induced nuclear AP-1-dependent gene expression in B lymphocytes. 163 70

To obtain an adequate amount of human prolactin (hPRL) for elucidation of the structure-function relationship, we have expressed the hPRL cDNA in Escherichia coli (E. coli) by using a high-expression vector. The vector contained a chimeric gene encoding a fusion of protein A, a peptide sensitive to collagenase digestion and hPRL, which was inserted downstream of the right direction promotor of lambda phage. The resulting protein fusion was purified through three column chromatographies of immunoglobulin G-linked Sepharose 4B, DEAE-5PW, and phenyl-5PW. In a typical experiment, a final sample with a purity of more than 80% was obtained with a recovery of more than 40% judged by enzyme-linked immunosorbent assay (ELISA). The fusion thus obtained was digested with collagenase, and protein reactive to anti-hPRL antibody was purified through phenyl-5PW column chromatography. The hPRL sample was found to be identical to authentic hPRL with respect to the amino acid composition and an N-terminal sequence of 20 residues, except that it contained an additional four amino acids at the N-terminal end. This peptide was presumed to be derived from the collagenase-target sequence. The hPRL thus obtained was found to be as active as the authentic hormone either immunologically judged by ELISA or biologically judged by the growth stimulatory effect on rat Nb2 lymphoma cells.
...
PMID:Efficient production of biologically active human prolactin in Escherichia coli. 166 26

Alpha 2-macroglobulin, a major glycoprotein component of plasma, is unique in its capacity to bind and inhibit the proteolytic activities of all classes of proteinases. Since proteinases implicated in cancer dissemination (type-IV collagenase, plasminogen activator, cathepsins B) are normal constitutents of blood, we have explored the hypothesis that elevated tissue levels of activated proteinases bound to alpha 2M might be detected in plasma of patients with cancer. To test this premise, blood was collected from 149 subjects (33 healthy controls, 31 patients with infections and non-malignant diseases, 16 with myeloproliferative disease, 10 with gastrointestinal cancer, 7 with genito-urinary cancer, 16 with lung cancer, 14 with lymphoma, 11 with miscellaneous cancers and 11 with chronic lymphocytic leukemia and myeloma). Plasma was assayed for alpha 2M-proteinase complexes using a sandwich ELISA which employs a mouse monoclonal antibody (MAb) that binds to a neo-antigenic determinant on complexed alpha 2M and a rabbit polyclonal anti-native human alpha 2M antibody. The concentration of complexed alpha 2M in healthy controls was 14.2 +/- 9.8 micrograms/ml (mean +/- standard deviation). No significant differences in complexed alpha 2M were noted between normal and cancer groups (range 7.4-14.6 micrograms/ml). On the basis of these data, we propose that, in patients with cancer, activated proteinases are bound locally to inhibitors in the tissues and are not available to form complexes with plasma alpha 2M. An alternative explanation is that proteinases are not secreted in excess by cancer cells in vivo.
...
PMID:Proteinase-alpha 2 macroglobulin complexes are not increased in plasma of patients with cancer. 171 Feb 7

The hypothesis that activation of the signal transduction pathways by environmental stress may lead to genetic instability was tested. Mouse T-lymphoma cells, GRSL13, were treated with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). The induction of transcription of c-fos, fosB, c-jun, junB and collagenase was studied as well as the mutation rate in the progeny of treated cells. It was found that mRNA levels of fosB, junB and collagenase, all known to be involved in the growth factor signal transduction pathway, were enhanced. No transcription of c-fos and c-jun was observed in control and TPA-treated cells. These results suggest that transcription of c-fos is not a prerequisite for the induction of transcription of collagenase. The degree of induction of the signal transduction pathway was dependent on culture conditions of the treated cells, growing cells having less response than stationary cells. The mutation rate was significantly enhanced in the progeny of TPA-treated cells from 4.2 X 10(-7) to 9.8 X 10(-7)/cell/generation. Fluctuation analysis showed that TPA leads to a temporary enhancement of the mutation rate up to the eighth generation after treatment. The enhancement of the mutation rate is less apparent in growing cells than in stationary cells (1.8- and 2.9-fold respectively) which, because the signal transduction pathways are less induced in growing cells than in stationary cells, is in agreement with the hypothesis that induction of the signal transduction pathway leads to genetic instability.
...
PMID:Concomitant induction of signal transduction pathways and genetic instability by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. 200 94

The motility of murine splenic lymphocytes stimulated nonspecifically by recombinant interleukin 2 (RIL-2) was studied in a three-dimensional collagen-gel system. Nonadherent BALB/c splenic lymphocytes were cultured in medium containing Cetus RIL-2 (700 to 1000 units/ml) or excipient control. They were then allowed to locomote randomly for 16 to 18 h into slabs of type I rat tail collagen gel. The gels were digested with collagenase, and total lymphocyte populations and motile subpopulations were collected and compared with respect to their lymphokine-activated killer activity (measured as 4-h cytotoxicity against the natural killer-resistant mammary adenocarcinoma line 410.4), their natural killer activity (measured as 4-h cytotoxicity versus lymphoma YAC-1), and their subset distribution (defined by immunofluorescence). Some of the slabs were not digested but fixed for measurement of leading-front distance. RIL-2-stimulated lymphocyte populations displayed greater motility than unstimulated populations; the mean leading front distance was 2.4 times greater, and the percentage of cells exhibiting motility was approximately doubled. The most motile RIL-2-stimulated cells, however, were not the most tumoricidal. Motile subpopulations displayed approximately 25 to 60% lower lymphokine-activated killer activity than did the total populations from which they were derived. Natural killer activity followed a similar pattern. Motile subpopulations contained a lower proportion of asialo-GM1+ and T-null cells than did total populations and a higher proportion of L3T4+ cells. Chemokinetic stimulation with alpha-interferon increased overall motility, but the lymphokine-activated killer activity of the motile subpopulation was still lower than that of the total population. Lymphocyte motility is important in the infiltration of tumors and other inflammatory lesions. The results indicate that the most tumoricidal lymphocytes in RIL-2-stimulated populations may not be the best tumor infiltrators, and that the tumoricidal activity of circulating lymphocytes may be a misleading indicator of the effectiveness of immunotherapy.
...
PMID:Motility and tumoricidal activity of interleukin-2-stimulated lymphocytes. 245 69

X-ray-induced, lymphoblastic, T-cell lymphoma/leukemias from irradiated RF mice were observed to uniformly expressed a 44-kd oncofetal antigen (OFA). The OFA polypeptide was detected by flow cytometry, affinity column SDS-PAGE analysis, and immunoblotting with monoclonal antibody (MAb) 115 prepared against syngeneic mouse fetus. X-ray and ultraviolet (UV) induced murine fibrosarcoma cell lines, used as classic models in radiation biology, were also found to express the OFA, which suggested that the 44-kd OFA was a general transformation marker of tumors. Adult mouse thymocytes and other adult tissues expressed no OFA. The 44-kd polypeptide was located at the surface membrane of the tumors examined. In contrast to other reports, lymphoblastic lymphoma cell lines expressed the OFA as a cross-protective, rather than an individually-specific, tumor-associated transplantation antigen. Pronase treatment removed OFA from the surface of living lymphoma cells, whereas collagenase, neuraminidase, and hyaluronidase did not. The OFA was rapidly reexpressed upon culture of the pronase-treated cells. Taken together, these results suggest that the 44-kd OFA polypeptide described here may provide a useful cell surface marker for future radiation carcinogenesis studies. MAb 115 is a promising reagent for detecting tumor-associated 44-kd OFA, for assessing immunoregulatory perturbations to the OFA caused by radiation damage and for investigating the immunopathology of OFA-associated radiation damage.
...
PMID:Radiation-induced lymphoblastic lymphomas/leukemias and sarcomas of mice express conserved, immunogenic 44-kilodalton oncofetal antigen. 333 9

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.
...
PMID:Role of B cells in the stimulation of syngeneic mixed lymphocyte responses. 624 30

The incorporation of methionine, lysine, and leucine into protein was studied in Ca2+-depleted and Ca2+-restored preparations of C-6 glial tumor cells in minimal medium. Although incorporation proceeded at linear rates in both preparations for more than 1 h and into the same spectrum of proteins, Ca2+-restored cells incorporated amino acid 5- to 10-fold more rapidly than Ca2+-depleted cells. Addition of approximately 200 microM Ca2+ in excess of chelator was required to achieve maximal rates of incorporation in Ca2+-depleted preparations. Stimulation by Ca2+ was rapid in onset (several minutes) and slowly reversible by chelator. Ca2+ was uniquely potent and specific among physiologically occurring cations in conferring such stimulation. Stimulation of amino acid incorporation by Ca2+ occurred over a broad range of pH and osmolarities and was facilitated by Mg2+. The effects of Ca2+ in stimulating amino acid incorporation were not traceable to changes in cAMP metabolism, amino acid uptake, protein catabolism, cell ATP or GTP content, or aminoacylation of transfer RNA. Actinomycin D (1 microgram/ml) did not block the stimulatory effects of Ca2+ although puromycin and cycloheximide did. The stimulatory effects of Ca2+ on protein synthesis were not restricted to C-6 in minimal medium. Protein synthesis was reduced by ethylene glycol bis(B-aminoethyl ether)-N,N,N',N'-tetraacetic acid 40 to 75% in C-6 glioma, GH3 pituitary tumor, PC-12 adrenal tumor, N2A neuroblastoma, and HeLa cells incubated under simulated growth conditions with various enriched media and sera. Ca2+-depleted S49 lymphoma, CHO ovarian tumor, and normal, dispersed chicken embryo cells in enriched medium responded to Ca2+ restoration with increased rates of protein synthesis as did collagenase-dispersed normal rat liver cells in minimal medium. Protein synthesis in rabbit reticulocyte lysates was also inhibited by Ca2+-selective chelators or by Ca2+ removal by parvalbumin affinity chromatography and the inhibition was reversed by Ca2+. These findings are consistent with the existence of a Ca2+ requirement in the translational phase of protein synthesis in eukaryotic cells.
...
PMID:Identification of a Ca2+ requirement for protein synthesis in eukaryotic cells. 631 27


1 2 3 Next >>

---