RESUMO
Acute-phase protein (APPs) serum levels have been studied in many human diseases, and their components contribute to host defense during the evolution of infectious diseases by acting as part of the innate immune system. Based on the importance of establishing new experimental models, the present investigation evaluated the modulation of APPs following inflammatory stimulus by the inoculation of Aeromonas hydrophila in tilapias. Fish were sampled 6 and 24 hours post-infection. Tilapias presented increase of positive APPs such as ceruloplasmin, haptoglobin, alpha-2-macroglobulin and complement C3, as well as decrease of negative APPs such as albumin and transferrin. The protein response of tilapias during the course of bacterial infection showed correlation with the kinetics of cellular accumulation in the inflamed focus with significant increase of granulocytes, thrombocytes, lymphocytes and macrophages. However, granulocytes were the predominant cells, associated with increment in the reactive oxygen species (ROS) production. Showing responses similar to those observed in humans, the modulation of APPs and the kinetics of cellular accumulation in the exudate demonstrate the feasibility of this alternative experimental model for advances and studies to understand changes in pathophysiological mechanisms of acute inflammatory reaction due to bacterial infection.
Assuntos
Proteínas de Fase Aguda/metabolismo , Infecções Bacterianas/microbiologia , Modelos Animais de Doenças , Proteínas de Peixes/metabolismo , Tilápia/imunologia , Proteínas de Fase Aguda/genética , Aeromonas hydrophila/patogenicidade , Animais , Infecções Bacterianas/imunologia , Proteínas de Peixes/genética , Tilápia/microbiologiaRESUMO
Modern subunit vaccines have excellent safety profiles and improved tolerability, but do not elicit strong immune responses without the addition of adjuvants. Developing a safe and affective adjuvant remains a challenge for peptide-based vaccine design. Growth Hormone Releasing Peptide-6 (GHRP-6) is one of the earliest-developed, synthetic, peptidyl growth hormone secretagogue receptor agonists. These compounds mimic the effect of the endogenous ligand, ghrelin. In the present study, we evaluated the ability of GHRP-6 to enhance the humoral immune response against co-injected antigens in mice, tilapia and African catfish. This peptide was able to increase the antigen-specific antibody response using heterologous proteins and peptides as antigens, which were also formulated in "water in oil" emulsions (Freund and Montanide). As long as we know there is no previous report describing any ghrelin analogous as molecular immunomodulator stimulating a humoral immune response. Further studies will be conducted to evaluate the functionality of this humoral immune response in challenge trials.
Assuntos
Anticorpos/imunologia , Peixes-Gato/imunologia , Ciclídeos/imunologia , Oligopeptídeos/imunologia , Tilápia/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Antígenos/imunologia , Feminino , Grelina/imunologia , Imunidade Humoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de Subunidades Antigênicas/imunologiaRESUMO
O objetivo desta revisão sistemática foi avaliar a eficácia das vacinas descritas na literatura para infecções causadas por S. agalactiae em tilápia. Uma busca eletrônica foi realizada utilizando o Web of Science, Scopus, PubMed e CAB bancos de dados diretos, abrangendo todos os artigos publicados até março de 2014. O delineamento experimental, a qualidade metodológica, tipo de vacina e os resultados dos estudos foram analisados. Foram avaliados protocolos de vacinação com base na administração intraperitoneal, banho de imersão e de alimentação. Esta revisão sistemática sugere que vacinas administradas por via intraperitoneal apresenta maior eficácia contra a infecção por S. agalactiae. (AU)
The aim of this systematic review was to evaluate the efficacy of the vaccines described in the literature for infections caused by S. agalactiae in tilapia .An electronic search was made of the "Web of Science", "Scopus", "PubMed" and "CAB direct" databasis in February and March 2014. The experimental design, methodological quality, type of vaccine and results of the studies were analyzed. Were evaluated vaccination protocols based on intraperitoneal routes of administration, immersion bath and feed. This systematic review suggests that vaccines administered intraperitoneally showed better efficacy against infection by S. agalactiae. (AU)
Assuntos
Animais , Streptococcus agalactiae , Potência de Vacina , Vacinas/análise , Tilápia/imunologia , Resultado do TratamentoRESUMO
O objetivo desta revisão sistemática foi avaliar a eficácia das vacinas descritas na literatura para infecções causadas por S. agalactiae em tilápia. Uma busca eletrônica foi realizada utilizando o Web of Science, Scopus, PubMed e CAB bancos de dados diretos, abrangendo todos os artigos publicados até março de 2014. O delineamento experimental, a qualidade metodológica, tipo de vacina e os resultados dos estudos foram analisados. Foram avaliados protocolos de vacinação com base na administração intraperitoneal, banho de imersão e de alimentação. Esta revisão sistemática sugere que vacinas administradas por via intraperitoneal apresenta maior eficácia contra a infecção por S. agalactiae.
The aim of this systematic review was to evaluate the efficacy of the vaccines described in the literature for infections caused by S. agalactiae in tilapia .An electronic search was made of the "Web of Science", "Scopus", "PubMed" and "CAB direct" databasis in February and March 2014. The experimental design, methodological quality, type of vaccine and results of the studies were analyzed. Were evaluated vaccination protocols based on intraperitoneal routes of administration, immersion bath and feed. This systematic review suggests that vaccines administered intraperitoneally showed better efficacy against infection by S. agalactiae.
Assuntos
Animais , Potência de Vacina , Streptococcus agalactiae , Tilápia/imunologia , Vacinas/análise , Resultado do TratamentoRESUMO
Probióticos são, em geral, considerados microrganismos vivos que, quando administrados em quantidades adequadas, conferem um benefício à saúde do hospedeiro. O método de processamento da dieta e a forma de inclusão do probiótico podem interferir nos parâmetros hematológicos, imunológicos e microbiológicos dos peixes. Objetivou-se estimar os parâmetros hematológicos, imunológicos e microbiológicos em juvenis de tilápia-do-nilo, alimentados com probiótico incluído antes e após o processamento de peletização e extrusão da ração. O delineamento experimental foi inteiramente casualizado,com cinco tratamentos: ração peletizada sem a inclusão do probiótico, ração peletizada com inclusão do probiótico antes e após o processamento, ração extrusada sem probiótico e ração extrusada com inclusão do probiótico após o processamento, e cinco réplicas. Duzentos e cinquenta peixes foram distribuídos em 25 aquários (20L) e alimentados durante 63 dias. Acomposição sanguínea (série vermelha e branca) não mostrou diferenças significativas, exceto a concentração de hemoglobina corpuscular média do controle quando comparados aos demais tratamentos. A capacidade fagocítica dos animais que receberam a dieta extrusada suplementada com probiótico foi significativamente superior, entretanto, para o índice fagocítico, não ocorreram diferenças entre os tratamentos. Os peixes alimentados com a dieta extrusada mostraram melhora na imunidade inespecífica. As bactérias probióticas colonizaram o intestino, pois foi possível recuperá-las. Pode-se afirmar que esses peixes mantiveram-se sadios, pois os parâmetros hematológicos não sofreram alterações durante o período experimental. O estudo revela que qualquer forma de inclusão de probióticos nas rações testadas(antes ou depois da peletização e após a extrusão)pode ser utilizada facilmente pelo piscicultor.(AU)
Probiotics are generally considered as live microorganisms which, when administered in adequate amounts, confer a health benefit to the host. The processing method of diet and the form of inclusion of probiotic can interfere in hematological, immunological and microbiological parameters in fish. The aimwas to estimate the hematological, immunological and microbiological parameters in juveniles of Nile tilapia, fed probiotic, included before and after the process of pelletizationand extrusion. The experimental design was completely randomized, with five treatments: pelleted diet without probiotic, pelleted diet with inclusion of probiotic before and after processing, extruded feed without probiotic and extruded feed with inclusion of probiotic after processingand five replications.Two hundred and fiftyfishwere distributed in 25 aquaria (20L) and fed for 63 days. The blood composition (red and white) showed no significant difference.(AU)
Assuntos
Animais , Tilápia/imunologia , Tilápia/microbiologia , Tilápia/sangue , Probióticos/administração & dosagem , DietaRESUMO
In teleosts fish, secretion of GH is regulated by several hypothalamic factors that are influenced by the physiological state of the animal. There is an interaction between immune and endocrine systems through hormones and cytokines. GH in fish is involved in many physiological processes that are not overtly growth related, such as saltwater osmoregulation, antifreeze synthesis, and the regulation of sexual maturation and immune functions. This study was conducted to characterize a decapeptide compound A233 (GKFDLSPEHQ) designed by molecular modeling to evaluate its function as a GH secretagogue (GHS). In pituitary cell culture, the peptide A233 induces GH secretion and it is also able to increase superoxide production in tilapia head-kidney leukocyte cultures. This effect is blocked by preincubation with the GHS receptor antagonist [d-Lys(3)]-GHRP6. Immunoneutralization of GH by addition of anti-tilapia GH monoclonal antibody blocked the stimulatory effect of A233 on superoxide production. These experiments propose a GH-mediated mechanism for the action of A233. The in vivo biological action of the decapeptide was also demonstrated for growth stimulation in goldfish and tilapia larvae (P<0.001). Superoxide dismutase levels, antiprotease activity, and lectin titer were enhanced in tilapia larvae treated with this novel molecule. The decapeptide A233 designed by molecular modeling is able to function as a GHS in teleosts and enhance parameters of the innate immune system in the fish larvae.
Assuntos
Carpa Dourada/crescimento & desenvolvimento , Hormônio do Crescimento/metabolismo , Imunidade Inata/efeitos dos fármacos , Oligopeptídeos/farmacologia , Tilápia/crescimento & desenvolvimento , Animais , Aquicultura/métodos , Bioensaio , Células Cultivadas , Carpa Dourada/imunologia , Imunidade Inata/imunologia , Modelos Moleculares , Oligopeptídeos/síntese química , Oligopeptídeos/metabolismo , Hormônios Peptídicos/farmacologia , Hipófise/citologia , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Tilápia/imunologiaRESUMO
Pichia pastoris cells transformed with a plasmid engineered for the expression of tilapia growth hormone as a secreted product produced a proteolytically cleaved form of the recombinant protein. The sequence of this truncated variant was obtained by mass spectrometry analysis. The cleavage site was determined to be between residues Tyr 158 and Tyr 159. The resulting truncated tilapia growth hormone was a single chain protein lacking 46 amino acids of the C-terminal portion. In this study, we showed that the truncated growth hormone produced in the P. pastoris culture supernatant has growth promoting effects and stimulates innate immune parameters (lysozyme and lectins) in tilapia larvae. These results suggest that the C-terminal portion of growth hormone is not required for its growth promoting activity and the innate immune functions studied herein in fish. In addition, we found that the culture supernatant containing truncated tilapia growth hormone has a stronger effect over growth and immune system than cells lysate containing intact tilapia growth hormone expressed in P. pastoris.