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Query: UMLS:C0850803 (anaphylaxis)
 8,092 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carrier and hapten functions have been studied in the immune deviation phenomenon. Delayed hypersensitivity to the carrier and anaphylaxis and Arthus hypersensitivities to the hapten and to the carrier were studied in guinea-pigs injected intravenously with large doses of carrier, homologous and heterologous hapten-carrier conjugates and subsequently immunized with the hapten-carrier conjugate in Freund's complete adjuvant. Pretreatment with DNP-BSA or with HGG were found to modify, in opposite directions, the hypersensitivity reactions induced by DNP-HGG in adjuvant. It is suggested that the hapten and carrier moieties of the antigen molecule might have antagonistic effects on the T cells responsible for cellular immunity as well as on T cells involved in helper functions for B cells.
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PMID:Carrier and hapten functions in immune deviation. I. Contrary effects of hapten and carrier on cellular and helper functions of T cells. 4 7

From the study of the effect of epitope density on the immunogenicity of haptenated ovalbumin (DNP-OA) it was concluded that the lightly haptenated conjugate, DNP0-5-OA, induced, on the one hand, only low titers of anti-DNP hemagglutinating antibody and no reaginic antibodies to the hapten and, on the other, high reaginic and high hemagglutinating antibody responses to the carrier. The conjugate with a slightly higher degree of haptenation, i.e., DNP2.3-OA, induced both reaginic and hemagglutinating antibodies to both the hapten and the carrier. By contrast, the heavily haptenated conjugate, DNP20-OA, elicited reaginic and hemagglutinating antibodies only against the hapten but not against the carrier. Specific suppression of anti-hapten reaginic antibody formation had been achieved by treatment of mice with a tolerogen consisting of the hapten (DNP) conjugated covalently to isologous gamma globulins (MgammaG). The epitope density of the DNPx-MgammaG conjugates was shown to play a dominant role in determining whether or not the conjugate was tolerogenic. Thus, lightly haptenated conjugates (DNP0.5-MgammaG, DNP1.3-MgammaG or DNP1.9-MgammaG) were not tolerogenic, moderately haptenated conjugates (DNP4.2-MgammaG, DNP8-MgammaG, and DNP 14-MgammaG) were tolerogenic, and heavily haptenated conjugates (DNP32-MgammaG and DNP53-MgammaG) were immunogenic, being capable of priming the recipients for the DNP hapten. Further evidence for the nonimmunogenicity of DNP 8-MgammaG conjugate was inferred from its rate of clearance in tolerized and normal mice. Thus, the half-life of 125I-labeled DNP8-MgammaG in circulation was not significantly different for normal and tolerized mice; it was 3.7 and 3.5 days, respectively, which is within the range of data reported for clearance of normal MgammaG. These results suggest that DNP8-MgammaG was catabolized at a rate similar to that of nonconjugated, isologous MgammaG. Moreover, there was no significant difference in the localization of DNP8-MgammaG in identical difference in the localization of DNP8-MgammaG in identical organs (spleen, thymus, kidney, and liver) of normal and tolerized mice. All the multivalent DNPx-MgammaG conjugates were shown to be able to elicit passive cutaneous anaphylaxis (PCA) reaction on i.v. challenge of rats which had been pre-sensitized i.d. with anti-DNP reaginic antibodies.
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PMID:Suppression of reaginic antibody formation. III. Relationship between immunogenecity and tolerogenicity of hapten-carrier conjugates. 5 48

Tolerance induction of IgE antibody-forming cells by dinitrophenylated levan (DNP-LE) conjugates was investigated in CBA mice. Antibody production was measured by passive coutaneous anaphylaxis on rat skin. Specific antibody neutralization was obtained with conjugates of different substitution degrees. Specific inhibition of IgE antibody production was obtained only with highly substituted conjugates. However, the epitope density required for inducing tolerance to antibody synthesis of the IgE class was lower than for other classes of immunoglobulins. The tolerance induced by DNP-LE was shown to affect only the anti-DNP B cells of IgE class without T cell participation. These results demonstrate that B cell precursors of all Ig classes are susceptible to tolerance induction and not to triggering by T-independent antigens.
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PMID:Role of epitope density in the induction of immunity and tolerance with thymus-independent antigens. IV. Selective tolerance and IgE response by DNP-levan conjugates. 7 72

Delayed hypersensitivity reactions (DHR) and anaphylactic reactions to carrier and hapten determinants were studied in guinea pigs immunized with DNP-mycobacterium and rendered partially tolerant to the carrier by a single intravenous injection of mycobacterium prior to immunization. The results clearly show that the induction of depressed DHR to mycobacterium leads to a suppression of DHR to the hapten while no depression of anaphylaxis to the hapten is observed. It is proposed that the tolerogenic treatment acts at the macrophage level rather than at the T cell level.
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PMID:Suppression of delayed hypersensitivity to the hapten by induction of tolerance to the carrier. 41 34

Bovine immunoglobulin G subclass (IgG1 and IgG2) antibodies were found to fix bovine complement while only IgG1 fixed guinea-pig complement in vitro. Similar results were noted when IgG1 and IgG2 antibodies were tested by passive cutaneous anaphylaxis (PCA) in that both IgG1 and IgG2 caused PCA in bovine skin while only IgG1 mediated the reaction in rat skin. In precipitation reactions IgG1 antibodies to DNP failed to cause precipitation of DNP19-ovalbumin while IgG2 antibodies to DNP precipitated DNP19-ovalbumin. Both IgG1 and IgG2 antibodies to ovalbumin precipitated ovalbumin. Surprisingly, IgG2 antibodies to equine erythrocytes caused phagocytosis by bovine neutrophils and peripheral blood monocytes while IgG1 antibodies failed to cause either phagocytosis or adherence. Results with peripheral blood monocytes cultured for 7 days demonstrated that both IgG1 and IgG2 could mediate phagocytosis.
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PMID:Functional properties of bovine IgG1 and IgG2: interaction with complement, macrophages, neutrophils and skin. 51 Dec 18

Antibodies in the sera of guinea pigs immunized with DNCB were detected by Ouchterlony-type analyses and were estimated in weight units by the mABC procedure. Assays of these sera by means of passive cutaneous anaphylaxis, passive hemolysis, or the ABC-33 antigen-binding technique were essentially negative. The validity of the mABC analyses was established by comparison of results obtained in quantitative precipitation studies with sera of guinea pigs immunized with DNP-BGG. In these instances, also, the ABC-33 assays failed to detect all the anti-DNP immunoglobulins.
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PMID:The humoral response to DNCB: its detection by different techniques. 80 22

Biologic properties of antibodies are known to be mediated by the Fc portion of the H chains. In the present study such properties as complement fixation, cutaneous anaphylaxis, and macrophage cytophilia were examined in relation to the CH2 and CH3 domains of rabbit IgG. Fragments containing but one of these domains were prepared from plasmin and papain digests. Facb fragments of anti-DNP antibodies, together with the antigen DNP-BSA, were able to fix complement by the classical pathway, a result which implicates the CH2 domain; however, guinea pig Fab fragments directed to regions of the rabbit antibody molecule other than CH2 were able to inhibit complement fixation. Facb fragments were unable to mediate PCA or reverse PCA reactions in guinea pigs, nor were CH3 fragments active in tests of reverse PCA or inhibition of PCA. These results suggest that the entire Fc region is needed for cutaneous anaphylaxis. The ability to bind to guinea pig lung macrophages was studied with a rosette technique. Facb fragments were active whereas CH3 fragments failed to inhibit. It is suggested that although some effector functions of antibodies can be assigned to individual domains, others require the entire Fc region.
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PMID:Biologic activities of rabbit immunoglobulin G in relation to domains of the Fc region. 81 12

Immunization of neonatal dogs with a conjugate of 2,4-dinitrobenzene and ovalbumin (DNP2-OA), using aluminum hydroxide as the adjuvant, elicited long-lasting (over 30 wk) anti-DNP and anti-OA IgE antibody responses of high titers as determined by homologous passive cutaneous anaphylaxis. Low antigen doses of 10 or 50 mug were more effective than the higher doses of 250 or 1,250 mug in inducing high IgE antibody levels. However, this method of immunization failed to elicity any detectable IgE antibody response in adult dogs. Bronchoprovocation with antigen of sensitized animals having IgE antibody titers in excess of 64 resulted in a marked increase in airflow resistance, which could be corrected by the administration of nebulized isoproterenol. On the other hand, sensitized animals with IgE antibody titers in the order of 64 did not manifest significant bronchoconstriction on inhalation challenge but developed anaphylaxis following intravenous injection of the antigen.
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PMID:A canine model for reaginic hypersensitivity and allergic bronchoconstriction. 83 75

In an active cutaneous anaphylaxis induced by DNP-ascaris extract in guinea-pig, tissue eosinophilia manifested two phases; the early and mild phase became maximal in about 6 h, while the delayed and intense phase in 18-24 h. Skin extracts from the lesions exhibited chemotactic activities for eosinophils, respectively comparable to the intensity of tissue eosinophilia in each phase; and two different chemotactic factors for eosinophils of skin extracts were separated by gel filtration on Sephadex G-100. The mediation of the early phase seemed to be associated with a thermostable factor with amolefular weight of less than 1400; this factor seemed to be related to mast cell degranulation. The mediation of the delayed phase appeared to be associated with a thermolabile factor with a molecular weight of about 70,000, probably independent of mast cell degranulation; the factor was considered to be more significant than the thermostable factor, because the delayed tissue eosinophilia was more intense than the early tissue eosinophilia.
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PMID:The mediation of tissue eosinophilia in hypersensitivity reaction. I. Isolation of two different chemotactic factors from DNP-Ascaris extract-induced skin lesion in guinea-pig. 126 51

An active model of ocular anaphylaxis was developed in guinea pigs to evaluate the histopathology of the early (EPR) and late (LPR) phase reaction, focusing on the role of mast cells. Five groups (n = 6) of animals were actively immunized by first injecting into each of the axillary and inguinal lymph node areas, 0.25 ml of an emulsion containing 1 mg dinitrophenyl bovine gamma-globulin (DNP-BCG) with 0.5 ml complete Freund's adjuvant. After two weeks, an intramuscular injection of 0.5 ml of an emulsion containing 1 mg DNP-BGG with 0.5 ml of incomplete adjuvant was administered. One month after the first injection, animals were sacrificed after topical ocular challenge with 10 microliters of 1 mg/ml divalent hapten, di-DNP-lysine, in one eye and phosphate buffered saline (PBS) in the fellow eye as control. Clinical reactions were graded over time and histology evaluated at the endpoint (time 0, 0.5, 3, 9, and 24 h). Results showed that all animals clearly developed both an EPR and an LPR, as either a biphasic, multiphasic or prolonged clinical response. A small percentage of mast cells were degranulated at baseline, whereas, at 0.5 h, 95% of mast cells were degranulated in the eyes treated with specific hapten and 25% in the control eyes treated with PBS. At 3 h, 84% of the mast cells were degranulated. This value rose to 89% at 9 h, and remained unchanged at 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Conjunctival mast cells and the allergic late phase reaction. 127 95


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