RESUMO
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.
Assuntos
Biomarcadores Tumorais , Liberação de Histamina/efeitos dos fármacos , Linfócitos/metabolismo , Linfocinas/metabolismo , Nippostrongylus , Infecções por Strongylida/metabolismo , Animais , Antígenos de Helmintos/farmacologia , Células Cultivadas , Linfócitos/efeitos dos fármacos , Linfocinas/efeitos dos fármacos , Masculino , Fito-Hemaglutininas/farmacologia , Ratos , Ratos Wistar , Proteína Tumoral 1 Controlada por TraduçãoRESUMO
Several parameters connected to histamine metabolism and mast cell number were examined in the lungs of rats infected with the nematode Nippostrongylus brasiliensis. Histamine levels as well as mast cell numbers were found to be increased on day 14 after infection and were elevated during the whole time of the experiment. Histidine decarboxylase activity also reached a peak on day 14. There was no measurable activity of diamine oxidase in the lungs of parasitized and normal rats. It is postulated that the increase in histidine decarboxylase activity and histamine concentration observed in the present study is related to the process of mastocytosis.
Assuntos
Histamina/metabolismo , Pneumopatias Parasitárias/metabolismo , Pulmão/metabolismo , Infecções por Nematoides/metabolismo , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Histidina Descarboxilase/metabolismo , Pulmão/enzimologia , Pneumopatias Parasitárias/enzimologia , Masculino , Mastocitose/metabolismo , Infecções por Nematoides/enzimologia , Nippostrongylus , Ratos , Ratos EndogâmicosRESUMO
The effect of disodium 4-chloro-2,2-iminodibenzoate (CCA) on IgE antibody response was examined in C3H/A and (BALB/c x C57BL/6J) F1 hybrid mice immunized with low doses of ovalbumin (OA) adsorbed on aluminium hydroxide gel. CCA administered orally at the doses of 5 and 50 mg/kg/day reduced IgE antibody production in these mice as determined by PCA test. High doses of CCA (100 mg/kg/day) given from day 7 before immunization of C57BL mice and during 1 week after immunization of mice with OA and Bordetella Pertussis Vaccine reduced the mortality of these mice subjected to anaphylactic shock on day 7 of immunization. CCA treatment was ineffective in anaphylactic shock of C57BL mice immunized with very high dose of OA, known to elicit little or no IgE antibody production but high IgG antibody response. The treatment of OA-immunized Guinea pigs with one oral dose of CCA (100 mg/kg) did not reduce mortality in protracted anaphylactic shock. Our results demonstrate that CCA inhibits IgE production as well as IgE mediated hypersensitivity reactions in mice.
Assuntos
Anafilaxia/tratamento farmacológico , Imunoglobulina E/efeitos dos fármacos , Imunossupressores/uso terapêutico , ortoaminobenzoatos/uso terapêutico , Anafilaxia/imunologia , Animais , Antígenos/imunologia , Feminino , Cobaias , Imunização , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Ovalbumina/imunologiaRESUMO
CCA(N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt is a new synthetic compound which structurally resembles mefenamic acid. CCA induces inhibition of the adjuvant arthritis in rats and has been reported as activator of suppressor T lymphocytes. These findings stimulated to us to elucidate whether or not CCA possesses inhibitory effects on immunoglobulin E (IgE) production, an immunological system in which T suppressor cells play a cardinal role. Mice F1 (BALB/c x C57BL/6J) and C3H/A were immunized using the procedure of several s.c. injections with low dose of ovalbumin and aluminium hydroxide gel. CCA (5 mg/kg and 50 mg/kg) was administered to mice several weeks by oral route. The titers of IgE were compared in controls and treated animals using the method of passive cutaneous anaphylaxis (PCA) in rats. At a dose of 5 mg/kg CCA reduced partially the titers of IgE in treated animals with respect to controls and at a dose of 50 mg/kg this inhibition was more pronounced. These results support a potential usefulness of CCA in bronchial asthma and other immediate type allergic disorders.