Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this investigation was to address the current controversy regarding the T-cell requirement for the generation of B-memory cells. We have circumvented the possible objection to previous experiments regarding residual T cells in T-deprived animals by examining memory cell generation in relation to the numbers of T cells participating in the immune response. Thymectomized and lethally-irradiated rats were reconstituted with foetal liver or a more mature stem cell source, neonatal liver. These animals were given graded doses of purified T cells one day before immunization with alum-precipitated DNP-BGG + Bordetella pertussis. Four weeks after priming, cell suspensions from experimental groups were adoptively transferred to carrier primed recipients and challenged with DNP-BGG in saline to assess memory cell development. The data demonstrate that in the absence of T cells only minimal memory development occurred. However, when T cells were present, the level of memory cell development increased with increasing numbers of T cells. By examining the relative affinity of the antibody produced in the primary and secondary responses, the increase in memory cell development in relation to increased numbers of T cells was shown to be due to the selective generation of high affinity memory B cells.
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PMID:Role of T cells in the development of memory B cells. Quantitative and qualitative analysis. 697 33

Hapten (DNP)-specific B-memory cells were induced by priming mice with soluble or alum precipitated DNP-haemocyanin (KLH) plus Bordetella pertussis or CNP-KLH-anti-DNP antibody complexes at equivalence. Cells from mice given complexes gave a substantial adoptive IgG response five days after priming, whereas those from mice given antigen with conventional adjuvant did not give a comparable response until day 14. Soluble antigen induced poor memory, even 14 days after primary immunization. The emergence of transferable B-memory cells correlated closely with the appearance of germinal centres in lymphoid follicles of the spleen. Furthermore, the relative affinity of the adoptive secondary IgG response induced by priming with complexes was already maximal on day 6. In contrast, the response of memory cells from mice given antigen on alum, increased in affinity between 6 and 23 days after priming. These data support the concept (see Klaus, Humphrey, Kunkl & Dongworth, 1980) that trapping of antigen-antibody complexes in lymphoid follicles induces the formation of germinal centres, which in turn give rise to functional B-memory cells. They further suggest that such retained complexes play a role in selective triggering of high-affinity precursor cells.
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PMID:The generation of memory cells. IV. Immunization with antigen-antibody complexes accelerates the development of B-memory cells, the formation of germinal centres and the maturation of antibody affinity in the secondary response. 701 54

PVG/c inbred rats were sensitized by intra-peritoneal injection of DNP 19-ovalbumin with or without heat-killed Bordetella pertussis as adjuvant. The use of adjuvant was associated with a greater serum IgE, greater cutaneous immediate hypersensitivity, but no increase in immediate pulmonary reactivity to aerosol challenge. The number of mast cells in the trachea of adjuvant-sensitized rats was significantly reduced when compared with both unsensitized and allergen sensitized rats but this reduction in mast cell number did not occur in the skin. The reduction in tracheal and possibly other airway mast cells may explain the failure of the adjuvant sensitized rats to show increased pulmonary reactivity despite the increased serum IgE. The B. pertussis may have acted on the mediastinal lymph nodes, which drain both the peritoneal cavity and the lungs, to produce the observed reduction in tracheal mast cells.
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PMID:Reduced tracheal mast cell numbers in adjuvant-sensitized rats associated with reduced pulmonary reactivity. 742 32

Crosslinking of the IgE receptor on rat basophilic leukemia (RBL) cells using the multivalent antigen DNP-BSA leads to a rapid and sustained increase in the filamentous actin content of the cells. Stimulation of RBL cells through the adenosine receptor also induces a very rapid polymerization of actin, which peaks in 45-60 s and is equivalent in magnitude to the F-actin response elicited through stimulation of the IgE receptor. However, in contrast to the IgE mediated response, which remains elevated for over 30 min, the F-actin increase induced by the adenosine analogue 5'-(N-ethylcarboxamido)-adenosine (NECA) is relatively transient and returns to baseline values within 5-10 min. While previous work has shown that the polymerization of actin in RBL cells stimulated through the IgE receptor is mediated by protein kinase C (PKC), protein kinase inhibitors have no effect on the F-actin response activated through the adenosine receptor. In contrast, pretreatment of the cells with pertussis toxin completely inhibits the F-actin response to NECA but has relatively little effect on the response induced through the IgE receptor. Stimulation of RBL cells through either receptor causes increased production of phosphatidylinositol mono-phosphate (PIP) and phosphatidylinositol bis-phosphate (PIP2), which correlates with the F-actin response. Production of PIP and PIP2 may be important downstream signals since these polyphosphoinositides are able to regulate the interaction of gelsolin and profilin with actin. Thus the polymerization of actin can be triggered through either the adenosine receptor or the IgE receptor, but different upstream signaling pathways are being used. The IgE mediated response requires the activation of PKC while stimulation through the adenosine receptor is PKC independent but involves a G protein.
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PMID:Polymerization of actin in RBL-2H3 cells can be triggered through either the IgE receptor or the adenosine receptor but different signaling pathways are used. 804 23

The amount of plasma IgE antibody formed and its change over time were investigated by enzyme-linked immunosorbent assay (ELISA) in male and female Sprague-Dawley (SD), Donryu, and Wistar strain rats. IgE antibody formation was initiated by injecting a mixture of 2,4-dinitrophenylated ascaris extract (DNP-As) as antigen and killed Bordetella pertussis as adjuvant into the paws of the animals. The amount of IgE antibody formed was low on day 10 in both male and female SD (40-80 ng/ml) and Donryu (20-40 ng/ml) strain rats, and an increase in the amount was observed on day 20. The peak value of IgE antibody was observed day 10 in Wistar strain rats and was 130 and 200 ng/ml in the male and female rats, respectively. These results suggest that Wistar strain rats produce the most IgE antibody when DNP-As is used as antigen and they can serve as a model for allergic diseases.
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PMID:Wistar strain rats as the model for IgE antibody experiments. 1151 Apr 95

We established a new and facile model to investigate allergic mechanism and assess the effect of antiallergic compounds. Male Wistar rats were actively or passively sensitized. Active sensitization was performed by injection of both dinitrophenylated-ovalbumin (DNP-OA) and Bordetella pertussis. Nine days later, DNP-OA was injected into the right hind footpad. This antigen challenge induced a biphasic footpad swelling that consisted of an early-phase (EPR) and a late-phase response (LPR). In rats passively sensitized with rat anti-DNP-OA serum, DNP-OA induced only EPR. The EPR was suppressed by disodium cromoglycate, a mast cell stabilizer, but not by cyclosporin A, an immunosuppressant, while the LPR was suppressed by cyclosporin A. Furthermore, to investigate these two allergic responses determined by the interactions between the hapten and the carrier proteins, two distinct haptenated antigens were created. DNP-Ascaris (DNP-As) induced a marked EPR and LPR in DNP-As-sensitized rats. However, DNP-As induced only EPR in DNP-OA-sensitized rats, indicating that the usage of the same carrier protein in both sensitization and challenge was necessary for induction of LPR. These data suggest that this actively sensitization model in which EPR and LPR are functionally distinguishable should be useful for evaluating the efficacy of antiallergic compounds.
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PMID:A late cutaneous response in actively sensitized rats: a new method for evaluating the efficacy of antiallergic drugs. 1689 62


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