Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The development of peritoneal mast cells in rats in the early post-natal period was found to take 7-8 weeks. A slightly shorter time was needed for the reappearance of mature peritoneal mast cells following their total destruction in adult rats. In both groups of animals mast cell ultrastructure was studied in successive phases of development. The maturation process was gradual, but no well-defined morphological stages could be demonstrated. The morphology of young peritoneal mast cells seems to indicate that they arise in the peritoneal fluid from macrophage-like cells.
Virchows Arch B Cell Pathol Incl Mol Pathol 1983
PMID:Electron microscopical study of rat mast cell maturation. 613 3

Type IV and V collagens were localized in neurofibromas from six patients with von Recklinghausen's neurofibromatosis (NF) using the peroxidase anti-peroxidase (PAP) technique. The collagens were also isolated from neurofibromas by pepsin digestion and fractionating salt precipitations and demonstrated with sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Staining reactions for both collagens were detected in most of the cells in the disorganized NF tumor tissue. These cells also were S-100 protein-positive and were considered to be of Schwannian cell origin, while the type IV collagen-negative cells showed fibroblastoid, mast cell and histiocytic characteristics. Type IV collagen detection was also used to study the structure of a neurofibroma after 3 weeks in tissue culture. The proportion of fibroblastoid, type IV collagen-negative cells increased significantly in the cultured neurofibromas and "buds" containing solely fibroblastoid cells were seen at the periphery of the tumor fragments. Cultured 6th passage tumor cells produced type V but no type IV collagen as estimated with SDS-PAGE. Further, two malignant Schwannomas from a patient with NF were stained with antibodies to type IV collagen. A positive staining reaction was associated only with the vascular walls in the malignant Schwannomas suggesting that type IV collagen expression is linked with cell differentiation. The present data show that the detection of type IV collagen using the PAP-method is useful in studying the organization of tumors with mixed cell populations such as neurofibromas. Large neurofibromas might also serve as a source for the isolation of human type IV and V collagens.
Virchows Arch B Cell Pathol Incl Mol Pathol 1984
PMID:Type IV and V collagens in von Recklinghausen's neurofibromas. An immunohistochemical and electrophoretical study. 615 10

The ferredoxin (Fd) molecule is a small non-mammalian immunogenic protein containing 55 amino acid residues with only two major antigenic determinants located with the NH2-terminal heptapeptide and the COOH-terminal pentapeptide. Selective enzyme cleavages of Fd with either trypsin or carboxypeptidase A result in the inactivation of the antigenic determinants by the removal of a tripeptide at the NH2-terminal and two amino acid residues at the COOH-terminal, effectively leaving 52 and 53 amino acid fragments respectively, each containing a single antigenic determinant. Fd digested with both enzymes yielded a 50 amino acid peptide with both determinants inactivated. Purity of these digests was assessed using monoclonal antibodies in standard and antigen-blocking ELISAs. The doubly digested peptide had virtually no reactivity with anti-Fd sera, reconfirming that the central cysteine-rich region is serologically silent. It was found that the sum of the reactivities of the N- and C-determinant-bearing peptides as equal to that of the native Fd and that the ratio of the reactivities could be used to assess determinant selectivity in the response to Fd in congenic recombinant strains of mice. This method was used in mapping the determinant selectivity in the antibody response to the MHC of mice to the left of the I-B subregion. Use of the B10.HTT strain indicated that separate genes mapping to the same subregion code for the magnitude of the antibody response and the determinant selectivity of the response.
Mol Immunol 1982 May
PMID:The use of unideterminant fragments of ferredoxin in the genetic mapping of determinant specificity of the immune response. 618 Mar 12

Mast cells secrete histamine, glycosaminoglycans, arachidonic acid derivatives, enzymes, and possibly whole granules. Physiologic stimuli include the bridging of membrane-bound IgE molecules by antigen, the anaphylatoxins C5a and C3a, and the neurotransmitter acetylcholine. Evidence is presented that a 'spontaneous' histamine release may be of biological significance. While the actual trigger of this process is unknown, it appears to be regulated by the concentration of histamine in the environment. It is suggested that the spontaneous release is responsible for maintaining a certain histamine concentration in the body fluids. After mast cell stimulation by IgE cross-linking or drugs changes in lipid metabolism, an influx of Ca2+ ions into the cell and fusions of the perigranular and the cytoplasmic membranes are observed. The physiologic role of the mast cell and its mediators is still a mystery.
Mol Immunol 1982 Oct
PMID:Triggering of mast cells. 618 14

This study demonstrated that mast-cell secretion elicited by intradermal injection of compound 48/80 initiated cell proliferation in rat skin. The mast-cell secretion was confirmed by microscopical demonstration of degranulation of mast cells, and by quantifying histamine release, whereas the proliferation was assessed by measuring DNA-synthesis and the frequency of mitosis. The results, which fully support our previous findings in the true mesentery, indicate that the common type of mast cell, when appropriately activated, is capable of playing a role in governing cell proliferation in diverse tissues.
Virchows Arch B Cell Pathol Incl Mol Pathol 1983
PMID:Intradermal mast-cell secretion causing cutaneous mitogenesis. 619 Mar 7

Several mouse monoclonal antibodies to carboxypeptidase A (CPA) were prepared and purified, and their interaction with the enzyme was investigated. CPA is a well-characterized zinc-containing exopeptidase exhibiting peptidase as well as esterase activity. The antibodies obtained could be classified as follows: antibodies inhibiting mainly the peptidase activity of the enzyme, antibodies inhibiting mainly its esterase activity, antibodies affecting both activities, and antibodies which bind to the enzyme but have no marked effect on its catalytic properties. Binding constants of approximately 10(6) M-1 were obtained for most of the antibody-enzyme complexes tested. Additional information on the effect of the monoclonal antibodies on the active site of CPA was obtained by determining the change in the circular dichroism spectra of arsanilazotyrosine-248 carboxypeptidase A occurring as a result of the interaction of the enzyme with the antibodies studied. These findings suggest that CPA possesses at least three different specific antigenic sites, and that the active site of the enzyme for its peptidase activity differs from that for its esterase activity, though both sites seem to overlap to a considerable extent.
Mol Immunol 1984 Jan
PMID:Interaction of carboxypeptidase A with monoclonal antibodies. 620 Jul 67

We have identified in soluble extracts of rat heart, a 500 000 dalton sulfhydryl-dependent protease which degrades globin and casein to acid-soluble peptides at an alkaline pH optimum. This enzyme was purified more than 1700-fold with respect to the postmicrosomal supernatant. On the basis of various catalytic and biochemical properties the enzyme appears similar to a recently described cytoplasmic protease in rat liver. Protease activity in vitro was stimulated up to 3-fold by physiologic concentrations of ATP and to a lesser extent by some other phosphate-containing compounds. Unlike some alkaline proteases reported in heart tissue, this high molecular weight protease was identified in extracts from isolated cardiac myocytes and in extracts from hearts of rats treated with the mast cell degranulating agent Compound 48/80. Thus, the identification of the protease in heart does not appear to be accounted for by mast cell contamination.
J Mol Cell Cardiol 1983 Jan
PMID:Identification of a high molecular weight alkaline protease in rat heart. 634 10

Previous studies had demonstrated that incubation of IgE with purified rat mast cells can result in the time and cell concentration-dependent destruction of the ability of the IgE to be bound to specific receptors on rat basophil leukemia cells. The IgE-destroying activity, which has an extremely acid pH optimum, resisted attempts at solubilization using detergents. However, it was solubilized in good yield by use of chaotropic salts and especially KOCN. The soluble activity is stable to freezing and thawing, and to heating to 68 degrees C for 60 min. It is promptly destroyed upon boiling. IgE destruction was linear with time up to 20 min and a series of products, mol. wts 138,000, 92,500, 60,000 and 36,500, are formed during the reaction. No pH optimum for the reaction could be found because, as the pH was lowered below 4.0, the spontaneous destruction of IgE became too great. At pH 4.75 the apparent Km for the reaction was 0.55 microM and Vmax was 0.4 nmoles IgE/10(4) mast cell equivalents/min. IgE-destroying activity could be inhibited by heat-inactivated serum, and by relatively high concentrations of crude alpha 1-antitrypsin, aprotinin, lima bean and soybean trypsin inhibitors and by p-nitroguanidinobenzoate. A large number of other protease inhibitors were inactive.
Mol Immunol 1982 Aug
PMID:Solubilization and initial biochemical characterization of an IgE-destroying enzyme on rat peritoneal mast cells. 675 97

The review of the contemporary state of bioinorganic chemistry is presented, illustrated by a series of examples. A short presentation of the chemistry of the complexes of transient metals is given, the importance of the distorsion isomerism is emphasized. The roles of the alkaline and alkaline-earth metals in biology is considered as also the role of Zn, Co, Mo, Cu. The function of iron is presented and the influence of magnetic fields on organisms is discussed. The mechanisms of action of carboxypeptidase A and of nitrogenase are considered. The general properties of metalloenzymes are discussed--the entatic state of the active site, the role of the distorsion isomerism and of the trans-effect as also the electronic-conformational interactions. The physical properties of the biometallic compounds are formulated. The importance of these compounds for medicine is illustrated by the Podymov's theory of lupus, by the cancerogenic role of metals and by the use of the platinum complexes in oncological therapy. The importance of biometallic compounds for enzymology and other branches of molecular biology is emphasized.
Mol Biol (Mosk)
PMID:[Bioinorganic chemistry and molecular biology]. 675 21

The human lymphoblastoid cell line BL was shown to synthesise three distinct molecular species of immunoglobulin M heavy chains: membrane-bound (micrometer). intracellular (micro i) and secreted (microseconds) micro-chains. Only the membrane-bound form could be labeled with a lipophilic photoactivatable nitrene reagent. Analysis of their constituent CNBr fragments and carboxypeptidase A and B digestions of their C-terminal tails suggest that the CNBr peptide pattern of microseconds and micrometer, though similar, is not identical, and that amino acids released at the C-termini of the chains are different. The data confirm recent observations in human and murine systems be showing that the membranes-associated human micro-chain contains a hydrophobic segment, consistent with its anchorage into the lipid bilayer of the plasma membrane and a C-terminal amino acid sequence different from that of the secretory micro-chain.
Mol Immunol 1982 Jan
PMID:Structural differences between heavy chains of secreted and membrane-bound IgM of a human lymphoblastoid cell line. 680 91


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