RESUMO
Recently, our group described the ether-à-go-go1(Eag1) voltage-gated potassium (K(+)) channel (Kv10.1) expression in the dopaminergic cells indicating that these channels are part of the diversified group of ion channels related to dopaminergic neurons function. The increase of dopamine neurotransmission induces a reduction in the prepulse inhibition (PPI) of the acoustic startle reflex in rodents, which is a reliable index of sensorimotor gating deficits. The PPI response has been reported to be abnormally reduced in schizophrenia patients. The role of Eag1 K(+) channels in the PPI reaction had not been revealed until now, albeit the singular distribution of Eag1 in the dentate gyrus of the hippocampus and the hippocampal regulation of the startle reflex and PPI. The aim of this work was to investigate if Eag1 blockade on hippocampus modifies the PPI-disruptive effects of apomorphine in Wistar rats. Bilateral injection of anti-Eag1 single-chain antibody into the dentate gyrus of hippocampus did not modify apomorphine-disruptive effects in the PPI response. However, Eag1 antibody completely restored the startle amplitude decrease revealed after dentate gyrus surgery. These potentially biological important phenomenon merits further investigation regarding the role of Eag1 K(+) channels, mainly, on startle reflex modulation, since the physiological role of these channels remain obscure.
Assuntos
Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/fisiologia , Hipocampo/fisiologia , Inibição Neural/fisiologia , Filtro Sensorial/fisiologia , Estimulação Acústica/métodos , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Apomorfina/farmacologia , Agonistas de Dopamina/farmacologia , Hipocampo/efeitos dos fármacos , Masculino , Inibição Neural/efeitos dos fármacos , Ratos , Ratos Wistar , Filtro Sensorial/efeitos dos fármacosRESUMO
Cancer-associated mucins show frequent alterations of oligosaccharide chain profile. Terminal structures may be deleted, thereby exposing normally 'cryptic' structures such as Tn (GalNAcα-O-Ser/Thr) and T antigen (Galß1-3GalNAcα-O-Ser/Thr). Overexpression of these commonly hidden glycoforms, and reduced level of naturally occurring anti-T or anti-Tn antibodies, is associated with epithelial tumor progression and aggressiveness. The lectin from the common edible mushroom Agaricus bisporus (ABL) shows high affinity binding to T antigen, and reversible noncytotoxic inhibitory effect on epithelial tumor cell proliferation. The aim of this study was to induce immune response with tumor-associated glycan specificity and biological activity similar to those of ABL. An anti-idiotypic (Id) antibody strategy was developed using ABL as first template. ABL was purified by affinity chromatography and assayed as immunogen in rabbit. Rabbit IgG was purified from anti-ABL serum using a protein G column, and specific anti-ABL IgG was obtained by affinity chromatography using immobilized ABL. Affinity-purified anti-ABL IgG contained an antibody fraction that recognizes the carbohydrate-binding site of ABL. This IgG was used as immunogen in mouse to yield anti-Id antibody recognizing tumor-associated glycans such as Tn and T antigen. Competitive assays showed that α-anomeric GalNAc is the main binding subsite of anti-Id antibody in glycan recognition. Anti-Id antibody bound human epithelial tumor cells, as shown by cell enzyme-linked immunosorbent assay and immunofluorescence. Anti-Id antibody raised by immunization with affinity-purified anti-ABL IgG had antiproliferative effect on human epithelial tumor cells through apoptosis induction similar to that of ABL. The anti-Id immune response developed here has potential application in cancer therapy.
Assuntos
Anticorpos Anti-Idiotípicos/farmacologia , Carcinoma/imunologia , Lectinas/imunologia , Agaricus/imunologia , Animais , Antígenos Virais de Tumores/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/imunologia , Células Cultivadas , Cromatografia de Afinidade , Epitopos/metabolismo , Imunofluorescência , Humanos , Imunização , Imunoglobulina G/imunologia , Lectinas/isolamento & purificação , Lectinas/metabolismo , Camundongos , Ligação Proteica/imunologia , CoelhosRESUMO
The effect of fluoxetine on mitogen-induced B-cell proliferation was studied. In particular, we analyzed the influence of fluoxetine on the signal transduction pathways triggered after stimulation with lipopolysaccharide (LPS) and anti-immunoglobulin M antibodies (anti-IgM). We showed that fluoxetine had a dual effect on anti-IgM-stimulated B-cell proliferation: at optimal anti-IgM concentration, fluoxetine inhibited proliferation, whereas at suboptimal anti-IgM concentration, the drug enhanced proliferation. Fluoxetine exerted only an inhibitory effect on LPS-induced B-cell proliferation. Calcium influx seemed to be involved in these effects.
Assuntos
Anticorpos Anti-Idiotípicos/farmacologia , Linfócitos B/efeitos dos fármacos , Fluoxetina/farmacologia , Lipopolissacarídeos/farmacologia , Animais , Antidepressivos de Segunda Geração/farmacologia , Linfócitos B/citologia , Transporte Biológico , Cálcio/metabolismo , Divisão Celular/efeitos dos fármacos , Interações Medicamentosas , Feminino , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB CAssuntos
Pulmão/patologia , Mastócitos/patologia , Nippostrongylus , Fenótipo , Pneumonia/parasitologia , Infecções por Strongylida/patologia , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Histonas/farmacologia , Imunoglobulina E/imunologia , Ionóforos/farmacologia , Masculino , Mastócitos/imunologia , Pneumonia/patologia , Polimixina B/farmacologia , Ratos , Ratos Sprague-Dawley , p-Metoxi-N-metilfenetilamina/farmacologiaRESUMO
BACKGROUND: The role of Pyroglyphid mites in IgE-mediated sensitization has been well established. Although mites belonging to the genus Dermatophagoides dominate in the acarofauna of domestic dust, non-pyroglyphid mites might also be of clinical importance. In Cuba, Dermatophagoides siboney is found in dust coexisting with D. pteronyssinus and Blomia tropicalis. Dermatophagoides farinae is not found. Storage mites, such as Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae, might also be present. OBJECTIVES: The aim of this study was to investigate the allergenic relationships among the mites present in the environment of allergic patients in Cuba. METHODS: The crossreactivity between an extract of D. siboney and the above mentioned six mites was studied by specific IgE inhibition, using sera of mite-sensitive patients after incubation with serial dilutions of D. siboney. RESULTS: The inhibitory effect of D. siboney extract was more pronounced against D. farinae, 91%, than against D. pteronyssinus, 62%. Specific IgE to B. tropicalis, A. siro, L. destructor and T. putrescentiae were inhibited to a much lesser extent, i.e. between 47 and 58%. The correlation between IgE to D. siboney and IgE to D. pteronyssinus and D. farinae was of 0.92 and 0.90, respectively. A weaker correlation was found between D. siboney and L. destructor (0.7), A. siro (0.67), B. tropicalis (0.54) and T. putrescentiae (0.51). CONCLUSION: Thus, D. siboney seems to be most closely related to D. farinae.
Assuntos
Asma/imunologia , Poeira/efeitos adversos , Glicoproteínas/imunologia , Hipersensibilidade Imediata/imunologia , Ácaros/imunologia , Adolescente , Adulto , Alérgenos/sangue , Alérgenos/imunologia , Alérgenos/farmacologia , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Especificidade de Anticorpos , Antígenos de Dermatophagoides , Asma/sangue , Ligação Competitiva/imunologia , Reações Cruzadas , Feminino , Glicoproteínas/sangue , Glicoproteínas/farmacologia , Humanos , Hipersensibilidade Imediata/sangue , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
Interleukin-4 (IL-4) is known to be involved in both the in vivo IgE response and the elevated B cell IgE Fc receptor (Fc epsilon R11) expression seen after a parasite infection. To further analyze the relationship between Fc epsilon R11 expression and IL-4 production, purified B cells from uninfected, Nippostrongylus brasiliensis (Nbr) infected and from goat anti-mouse IgD (GaM delta) injected mice were isolated on various days post-treatment. The Fc episolon R11 levels on purified B cells from normal mice decreased after an overnight culture in media alone and addition of IL-4 to these cultures resulted in a 4 to 13-fold enhancement of Fc epsilon R11 levels. In contrast, the Fc epsilon R11 levels on B cells from Nbr infected mice were elevated after an overnight culture in media alone and addition of IL-4 did not further enhance the already upregulated Fc epsilon R11 levels. Overnight culture of purified B cell blasts from Nbr infected mice in the presence of an anti-IL-4 monoclonal antibody (11B11) caused the elevated Fc epsilon R11 levels to return to levels seen in normal mice, without affecting the Fc epsilon R11 levels on purified Go or B cell blasts from uninfected mice or Go B cells from Nbr infected mice. 11B11 also inhibited the elevated Fc epsilon R11 levels on highly purified B cells obtained by FACS sorting the non-adherent spleen cell population for class II+ cells. In contrast to Nbr infection, the Fc epsilon R11 levels on B cells were downregulated in the GaM delta injected mice. However, analogous to the Nbr system, the Fc epsilon R11 levels were unresponsive to the addition of exogenous IL-4. This study indicates that IL-4 production is seen in T depleted splenocytes and that this alternate source of IL-4 serves to maintain the elevated Fc epsilon R11 levels on B cells.