Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of three glucocorticoids (steroids: hydrocortisone, prednisolone and dexamethasone) on IgE antibody-mediated immediate hypersensitivity reactions in rats were studied. Forty-eight hr homologous passive cutaneous anaphylaxis (PCA) was inhibited in a dose response manner by the administration of steroids 2 hr prior to challenge. When steroids were administered at various times before challenge, each steroid showed different patterns of time courses for inhibition of homologous PCA. Maximum inhibition was obtained 2 hr after the administration of each steroid. The IgE antibody-mediated histamine release from peritoneal mast cells in vivo was inhibited by the administration of steroids. Time-courses for the inhibitory effects of steroids on histamine release were slightly different from those in PCA. The increase of capillary permeability caused by histamine, serotonin, trypsin or hyaluronidase in the rat skin was not affected by steroids. The inhibitory action of steroids on PCA was not influenced by non-corticoidal steroids (17 alpha-methyltestosterone, androstenedione and progesterone) or arachidonic acid. These results partially explain the inhibitory action of steroids on IgE antibody-mediated immediate hypersensitivity. The inhibition of histamine release would contribute towards the anti-allergic action of steroids but not the antagonistic effect on the mediators. Also the action of glucocorticoids receptor or the inhibition of arachidonic acid production are not vitally important in connection with the anti-allergic action of steroids.
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PMID:Anti-allergic action of glucocorticoids in rats. 619 4

The immune response to honey bee venom in thirty-seven bee keepers' sera was studied by several methods. Specific IgE antibody levels studied by RAST were generally low, whereas specific IgG antibody levels studied by a Sepharose protein A technique were high. Crossed radioimmunoelectrophoresis was applied for a detailed analysis of the antibody specificities towards the different components of venom in seventeen of the bee keepers' sera. Significant amounts of IgG antibodies were found towards most bee-venom components. The highest IgG response was directed towards phospholipase A. Hyaluronidase, acid phosphatase and two uncharacterized antigens also showed distinct IgG binding. The IgG binding to melittin was low. The IgE binding to the bee venom components was low and primarily directed to the phospholipase. IgE binding to hyaluronidase and acid phosphatase occurred, but was also in very small amounts. One bee-keeper serum caused heavy radiostaining to melittin but the others did not show IgE binding to this component. Thus a low IgE but a high IgG response was demonstrated in bee keepers. The major immunogen was phospholipase A, which is known to be the major allergen in bee venom. Generally, the strongest IgG responses were found to the components capable of inducing the strongest IgE responses.
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PMID:Bee keepers' IgG and IgE antibody responses to bee venom studied by means of crossed radioimmunoelectrophoresis. 620 90

IgE antibodies to purified proteins and peptides from honeybee venom have been measured by the RAST. Trace amounts (less than 0.1%) of the major venom protein phospholipase A2 (PLA2) grossly distorted the measurement of IgE antibody to the other venom proteins, acid phosphatase (Acid P) and hyaluronidase (HYAL), and overemphasized their importance. Reduction of antigen coupled to the cellulose paper discs, which were used in the assay, diluted out the contaminating PLA2 without apparent loss in sensitivity. The reduction of disc-bound antigen increased the competition between IgE and IgG antibodies but did not affect measurement of IgE antibodies in sera taken from 35 untreated patients who had a history of general allergic reactions to bee stings. In 54% of sera from bee venom--allergic patients, the greatest IgE antibody response was to PLA2. In all, IgE antibodies to PLA2 were present in 91% of these sera. IgE antibodies to Acid P, HYAL, or melittin were present in 60%, 51%, and 31% of sera, respectively, and accounted for the highest level of binding in 17%, 17%, and 6% of these. Only 6% of sera were positive for whole venom but negative for the isolated antigens. A low level of IgE antibody was found to peptide 401 in 6% of sera. No IgE antibodies were found to apamin. While confirming the central role played by PLA2 in bee sting allergy, these results show that other venom components are also important in some patients.
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PMID:Antibodies to purified bee venom proteins and peptides. I. Development of a highly specific RAST for bee venom antigens and its application to bee sting allergy. 660 72

Antibodies to individual bee venom antigens were studied in detail in nine bee sting-allergic patients who received venom immunotherapy without side effects, in two patients who failed to reach maintenance, and in two whose sensitivity returned. The study was confined to patients who had IgE antibodies to at least one of four purified bee venom antigens at the start of treatment. IgE and IgG antibodies to phospholipase A2 (PLA2), hyaluronidase (HYAL), and acid phosphatase (ACID P) and IgE antibodies to melittin (MEL) were measured, and changes in the antibody levels were followed during bee venom immunotherapy. Two contrasting patterns of antibody response were seen in the nine successfully treated patients. In five patients there was a rise in serum IgG antibodies to the same antigens as the IgE antibodies. In two patients' serum IgE antibody to HYAL or ACID P fell without a marked IgG antibody response to these antigens, although high levels of IgG antibody to PLA2 were present in both. Although the first pattern is consistent with a "blocking" role for IgG antibody, clearly the second is not. Not all patients can be conveniently divided into these two categories, and two patients did not show any significant change in either IgG or IgE antibody but were nevertheless able to tolerate the maintenance dose of 100 micrograms of venom. Two patients who failed to reach the maintenance dose of 100 micrograms because of their allergic reactions to the injections of venom were distinguished by (1) very high serum IgE antibody and (2) a low ratio of IgG/IgE antibody. Passive immunization with IgG antibody from a hyperimmune beekeeper was, however, protective in these patients, although it did not raise their overall serum IgG antibody level very much. We are unable to explain either the failure of conventional therapy or the beneficial effect of passive immunization in these two patients. Two bee sting--allergic beekeepers lost their sensitivity to stings, but later, when their sera contained IgE antibody to another bee venom antigen, they reacted to stings and inhalation of beehive dander. These data suggest that either falling IgE antibody or IgG- "blocking" antibody could be responsible for providing clinical protection to bee venom--allergic subjects. Renewed clinical sensitivity was observed when the IgE response was modulated, with patients making IgE antibody first to one antigen and then to another.
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PMID:Antibodies to purified bee venom proteins and peptides. II. A detailed study of changes in IgE and IgG antibodies to individual bee venom antigens. 661 52

Pure Vespula maculifrons venom was demonstrated to contain five major allergenic proteins, which were all isolated from commercial venom sac extract. The five proteins: Vmacl, MW 97,000; hyaluronidase, MW 46,000; Vmac3, MW 39,000; phospholipase A and B, MW 34,000; and antigen 5, MW 22,000 were all demonstrated to be biochemically and immunologically distinct. All five proteins had significant allergenic activity, with phospholipase and hyaluronidase demonstrating the most IgE binding with 39 sera from allergic patients. Sera from honeybee-reactive patients, who had weak cross-reactions with yellow jacket venom, demonstrated strong IgE binding to purified V. maculifrons hyaluronidase and Vmacl. Dose-dependent inhibition of RAST was observed by use of honeybee hyaluronidase and high-molecular-weight fraction to inhibit the binding to the corresponding yellow jacket allergen.
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PMID:Allergens in Hymenoptera venom XI. Isolation of protein allergens from Vespula maculifrons (yellow jacket) venom. 673 87

The major proteins of yellowjacket venoms have been isolated and characterized immuno-chemically. They consist of hyaluronidase, phospholipase, and antigen 5. Venoms from three species of yellowjacket were studied. Vespula germanica, V. maculifrons, and V. vulgaris. The phospholipases could be isolated in good yield only when affinity chromatography was used to minimize limited proteolysis. A kallikrein-like peptidase was found present in the yellowjacket venom. Phospholipases from these three species were immunochemically indistinguishable from each other, as were their antigen 5s. Sera from individuals sensitive to yellowjacket venom contained IgE and IgG specific for antigen 5 and phospholipase.
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PMID:Immunochemical studies of yellowjacket venom proteins. 686 52

Twenty-three patients aged five to 52 years with good clinical histories of severe systemic reactions to hymenoptera stings confirmed by skin tests and RAST levels were treated with specific insect venoms. A more conventional, slow, bi-weekly schedule was used to determine whether they could be as successfully treated as those in earlier studies employing the "Rush desensitization" approach. It was also hoped these subjects would experience fewer untoward reactions. Comparisons of IgG (anti-hyaluronidase and phospholipase) levels pretreatment and after top dose (100 mcg) in all cases showed greater than three-fold rise, indicating protection. RAST IgE rose in most cases and plateaued by six months. Nineteen patients were restung to verify protection. Untoward reactions to injections were low (13%) and easily controlled. The authors conclude that the use of specific freeze dried insect venoms in a slow dose schedule is safe and effective in protecting severely sensitized individuals.
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PMID:Venom immunotherapy: comparison of "rush" vs "conventional" schedules. 744 83

We have isolated and characterized the human cardiac mast cell (CMC) and compared this novel mast cell (MC type with MC obtained from uterus, skin, and lung. Heart tissue was obtained from 14 patients with cardiomyopathy (CMP, heart transplantation). CMC were isolated by enzymatic digestion using collagenase, pronase-E, hyaluronidase, and DNAse. Substantial amounts of CMC (0.5% to 1.5% of isolated cells) were found in the atrial appendages but not in ventricular digests or other sites of the heart (< 0.1%). In situ staining of atrial tissue revealed the presence of CMC in the myocardium (2.16 +/- 0.7 MC/mm2), endocardium (2.24 +/- 0.9 MC/mm2), and epicardium. As assessed by combined toluidine blue/immunofluorescence staining with monoclonal antibodies (MoAbs), isolated CMC expressed surface IgE, the receptor for stem cell factor (c-kit receptor/CD117), the p24 antigen (CD9), the Pgp-1 homing receptor (CD44), the pan leukocyte antigen (CD45), and the ICAM-1 antigen (CD54). CMC were not recognized by MoAbs to lymphocyte function associated antigen 2 (LFA-2; CD2), T-cell receptor (TcR; CD3), T4 antigen (CD4), LFA-1 alpha-chain (CD11a), C3biR alpha-chain (CD11b), CR4 alpha-chain (CD11c), LPS-R related Ag (CD14), 3-FAL/x-hapten (CD15), Fc gamma RIII (CD16), lactosylceramid (CDw17), the B-cell antigen CD19, or CR1 (CD35). In situ expression of leukocyte antigens on CMC was demonstrable by indirect immunoperoxidase staining technique and double-labeling immunohistochemistry. Almost all CMC (90%) reacted with MoAbs against tryptase and chymase and thus were MCTC. Cardiac mast cells were also stained by the heparin-binding dye Berberine sulfate and expressed measurable amounts of histamine (4.6 +/- 1.4 pg per cell). Cross linking of either IgE receptor or SCF receptor (c-kit) on CMC resulted in histamine secretion (non-specific release: < 6% of total histamine, alpha IgE induced: 12% to 52%; SCF-induced release: 9% to 18%), whereas neither substance P (a skin MC agonist) nor the basophil agonist FMLP showed an effect on CMC. Together, the CMC is an MCTC primarily located in the appendage of the atrium. This novel type of MC exhibits surface membrane antigen and functional properties similar to those of lung and uterus MC.
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PMID:The human cardiac mast cell: localization, isolation, phenotype, and functional characterization. 752 50

White face hornet (Dolichovespula maculata) venom has three known protein allergens which induce IgE response in susceptible people. They are antigen 5, phospholipase A1, and hyaluronidase, also known as Dol m 5, 1, and 2, respectively. We have cloned Dol m 2, a protein of 331 residues. When expressed in bacteria, a mixture of recombinant Dol m 2 and its fragments was obtained. The fragments were apparently generated by proteolysis of a Met-Met bond at residue 122, as they were not observed for a Dol m 2 mutant with a Leu-Met bond. Dol m 2 has 56% sequence identity with the honey bee venom allergen hyaluronidase and 27% identity with PH-20, a human sperm protein with hyaluronidase activity. A common feature of hornet venom allergens is their sequence identity with other proteins in our environment. We showed previously the sequence identity of Dol m 5 with a plant protein and a mammalian testis protein and of Dol m 1 with mammalian lipases. In BALB/c mice, Dol m 2 and bee hyaluronidase showed cross-reactivity at both antibody and T cell levels. These findings are relevant to some patients' multiple sensitivity to hornet and bee stings.
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PMID:Sequence identity and antigenic cross-reactivity of white face hornet venom allergen, also a hyaluronidase, with other proteins. 787 12

This study was carried out to compare the allergenic potency of Vespula germanica (VG) venoms extracted by different methods and commercially available venoms from Vespula species currently used for in vivo and in vitro studies including immunotherapy. Pure VG venom was used as the reference material. Protein content and enzymatic and allergenic properties of all venoms studied were determined by dye stain reagent, hyaluronidase and phospholipase A1B enzyme activities, and radioallergosorbent test inhibition studies, respectively. Radioallergosorbent test discs sensitized with commercial and pure VG venom were compared using specific IgE antibodies from subjects allergic to VG venom. The data obtained indicate that there were important differences in the allergenic potency between the Vespula species venoms employed for in vivo and/or in vitro assays, VG venom obtained by sac dissection, and pure VG venom. These results indicate that venoms from Vespula species used for in vitro and in vivo tests have a lower concentration of allergens and contain nonvenom proteins. These data should be taken into account when these vespid venoms are used for diagnostic purposes and also when evaluating immunotherapy studies.
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PMID:Comparison of Vespula germanica venoms obtained from different sources. 803 17


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