Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histamine-ovalbumin conjugates were characterized in respect to the relative amount of histamine residues which are accessible to membrane receptors. These conjugates were bound to a protein carrier. Spleen cells exhibited an enhanced reactivity in the adoptive antibody production as well as the graft versus host reaction after filtration through affinity columns with a low density of histamine residues. Contrary to that, the use of affinity columns with high histamine density led to a reduced immunoreactivity of the nonadherent cells. Consequently, controversial literature data concerning this problem seem to be based on methodological differences. The results support the hypothesis, that suppressor cells carry more histamine receptors than other immunoreactive cells.
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PMID:[Histamine receptor-bearing lymphocytes. VII. Antibody formation and graft-vs-host reaction from spleen cells after separation on histamine affinity columns]. 295 90

Histamine is known to mediate potent immunosuppressive effects on lymphocyte function. In jirds infected with Brugia pahangi decreased mitogen and parasite antigen responsiveness are associated with the presence of histamine binding regulatory cells. The present study was thus designed to investigate the immunoregulatory role of histamine in experimental filariasis. Spleen cells from normal or B. pahangi infected jirds were incubated with BSA or histamine coupled Sepharose beads and the degree of cell-bead binding was quantitated. Cells from infected jirds demonstrated increased levels of histamine, but not BSA binding relative to normal cells, and this binding was blocked by soluble histamine or by the histamine receptor antagonist cimetidine. Cimetidine failed to restore the in vitro responsiveness of spleen cells from infected jirds to phytohemagglutinin or to a soluble extract of B. pahangi. Cimetidine did, however, reverse histamine-induced suppression of normal spleen cell responses to PHA. The present results suggest that histamine does not play a major role in the immunoregulatory alterations induced by B. pahangi infection.
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PMID:Failure of the H2 antagonist cimetidine to reverse parasite antigen-specific lymphocyte unresponsiveness in experimental filariasis. 321 1

The influence of Nippostrongylus brasiliensis infection on the capability of HRF (Histamine Releasing Factor) generation by rat lymphoid cells in vitro has been studied. Spleen cells and thymocytes of normal and Nippostrongylus brasiliensis-infected rats were cultured in the presence of nonspecific mitogen (PHA) or specific N. brasiliensis antigen (NbAg), and cell-free supernatants fractionated by Sephadex G-75 chromatography were tested on homologous mast cells for histamine releasing activity. The results show that PHA-stimulated lymphoid cells from both normal and infected rats produced a factor releasing histamine from mast cells. Histamine releasing activity was not detected when lymphoid cells of N. brasiliensis-infected rats were cultured in the presence of NbAg. Moreover, supernatants of these cultures diminished HRF-induced histamine release from mast cells, suggesting the production of factor(s) inhibiting this release. This histamine release inhibiting activity was detected in fractions in Sephadex G-75 chromatography of supernatants from the cultures of NbAg-stimulated thymocytes of infected rats.
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PMID:Histamine releasing activity and its inhibition by supernatants from cultured lymphoid cells of Nippostrongylus brasiliensis-infected rats. 768 73