ABSTRACT
OBJETIVO: Determinar se um protocolo curto de sensibilização com ovalbumina subcutânea, sem adjuvante, induziria uma resposta pulmonar eosinofílica em pulmões de camundongos similar àquela encontrada em protocolos previamente estabelecidos. MÉTODOS: Fêmeas adultas de camundongos BALB/c foram randomizadas e divididas em grupos de acordo com o número de sensibilizações com ovalbumina e o número/dosagem de provocação intranasal. O protocolo curto (10 dias) consistiu de uma sensibilização e três provocações com ovalbumina (100 µg). A contagem total e diferencial de células no lavado broncoalveolar, o nível de peroxidase eosinofílica no tecido pulmonar e o exame histopatológico dos pulmões foram realizados 24 h após a última provocação. RESULTADOS: Não houve diferenças significativas entre os grupos em relação às variáveis estudadas. O protocolo curto, assim como os outros protocolos estudados, induziu uma resposta eosinofílica pulmonar semelhante àquela do grupo controle positivo. CONCLUSÕES: A sensibilização por ovalbumina subcutânea sem o uso de adjuvante resultou em uma significativa resposta pulmonar alérgica em ratos, mesmo no grupo de protocolo curto. Nossos achados sugerem que esse protocolo curto pode ser utilizado como teste pré-clínico de primeira linha para a pesquisa de novos fármacos, reduzindo custos e o tempo de observação.
OBJECTIVE: To determine whether a short-term protocol using subcutaneous sensitization with ovalbumin, without the use of adjuvants, would induce an eosinophilic response in the lungs of mice similar to that observed in previous, well-established protocols. METHODS: Adult female BALB/c mice were randomized and divided into groups according to the number of sensitizations with ovalbumin and the number/dosage of intranasal ovalbumin challenges. The short-term protocol (10 days) consisted of one sensitization with ovalbumin and three ovalbumin challenges (100 µg). Total and differential cell counts in BAL fluid, levels of eosinophil peroxidase in lung tissue, and histopathological examination of the lungs were performed 24 h after the last ovalbumin challenge. RESULTS: No significant differences were found among the groups regarding the variables studied. The short-term protocol, as well as the other protocols studied, induced an eosinophilic response similar to that obtained in the positive control. CONCLUSIONS: Subcutaneous sensitization with ovalbumin and without the use of adjuvants resulted in a significant allergic response in the lungs of mice, even in the short-term protocol group. Our findings suggest that this short-term protocol can be used as a first-line pre-clinical test for the study of new medications, reducing the costs and observation periods.
Subject(s)
Animals , Female , Mice , Asthma/pathology , Bronchial Hyperreactivity/pathology , Eosinophil Peroxidase/metabolism , Lung/pathology , Ovalbumin , Pulmonary Eosinophilia/immunology , Acute Disease , Asthma/enzymology , Bronchial Provocation Tests , Bronchial Hyperreactivity/enzymology , Bronchoalveolar Lavage Fluid/cytology , Disease Models, Animal , Lung/enzymology , Mice, Inbred BALB C , Pulmonary Eosinophilia/pathology , Random AllocationABSTRACT
Several antigens from the microfilarial stage of Wuchereria bancrofti have been identified using immunoblots of microfilarial antigens and screening with immune sera and tropical pulmonary eosinophilia (TPE) sera. This analysis revealed an array of antigens with apparent molecular weights of 14kDa, 35kDa, 42kDa, 63kDa, 88kDa, 97kDa and 200kDa. Among these only the 14kDa and 42kDa antigens were consistently recognized by most of the immune sera. A 132kDa antigen was recognized only by TPE sera. Analysis of rabbit immune sera revealed that the 42kDa antigen was shared by two developmental stages of W. bancrofti, namely L3 and mF. This antigen could become a potential vaccine candidate. The 14kDa antigen seems specific for the microfilarial stage and therefore could be a diagnostic marker for active infection. The 132kDa antigen could aid in the diagnosis of TPE.
Subject(s)
Animals , Antibodies, Helminth/blood , Antigens, Helminth/diagnosis , Cross Reactions , Filariasis/diagnosis , Fluorescent Antibody Technique , Humans , Immune Sera , Immunization , Immunoblotting , Microfilariae/immunology , Molecular Weight , Pulmonary Eosinophilia/immunology , Rabbits , Vaccines/immunology , Wuchereria bancrofti/growth & developmentABSTRACT
Twenty six patients (24 males and 2 females) with tropical pulmonary eosinophilia (TPE) were studied. Arterial blood gas analysis, pulmonary functions, peripheral blood examination and bronchoalveolar lavage (BAL) were performed. Peripheral blood and BAL fluid analyses were performed in healthy volunteers. Pulmonary functions revealed a mild restrictive ventilatory defect with airways obstruction. Mild hypoxaemia was observed on arterial blood gas analysis. Serum immunoglobulins IgG (P < 0.01), IgA (P < 0.001) and IgM (P < 0.001) were significantly raised as compared to normal controls. Serum complement (C3) level was higher, however, it was not significantly different as compared to normal controls. Serum haemolytic component of the complement (CH50) was significantly higher (P < 0.001) in patients with TPE compared to normal control subjects. The immunoglobulins IgG, IgA and IgM in the BAL fluid were significantly (P < 0.001) increased as compared to normal controls. The fibronectin (FN) level was also significantly increased (P < 0.001) in the BAL fluid. It is concluded that patients with TPE have mild restrictive ventilatory defect with airways obstruction and mild hypoxaemia. They have eosinophilic alveolitis with increased levels of immunoglobulins in the peripheral blood and BAL fluid. The significance of elevated FN in the BAL fluid is not clear and serial estimations may have to be done in order to clarify its role in the pathogenesis of fibrosis in chronic TPE.