Orientia tsutsugamushi Stimulates an Original Gene Expression Program in Monocytes: Relationship with Gene Expression in Patients with Scrub Typhus

Orientia tsutsugamushi is the causal agent of scrub typhus, a public health problem in the Asia-Pacific region and a life-threatening disease. O. tsutsugamushi is an obligate intracellular bacterium that mainly infects endothelial cells. We demonstrated here that O. tsutsugamushi also replicated in monocytes isolated from healthy donors. In addition, O. tsutsugamushi altered the expression of more than 4,500 genes, as demonstrated by microarray analysis. The expression of type I interferon, interferon-stimulated genes and genes associated with the M1 polarization of macrophages was significantly upregulated. O. tsutsugamushi also induced the expression of apoptosis-related genes and promoted cell death in a small percentage of monocytes. Live organisms were indispensable to the type I interferon response and apoptosis and enhanced the expression of M1-associated cytokines. These data were related to the transcriptional changes detected in mononuclear cells isolated from patients with scrub typhus. Here, the microarray analyses revealed the upregulation of 613 genes, which included interferon-related genes, and some features of M1 polarization were observed in these patients, similar to what was observed in O. tsutsugamushi-stimulated monocytes in vitro. This is the first report demonstrating that monocytes are clearly polarized in vitro and ex vivo following exposure to O. tsutsugamushi. These results would improve our understanding of the pathogenesis of scrub typhus, during which interferon-mediated activation of monocytes and their subsequent polarization into an M1 phenotype appear critical. This study may give us a clue of new tools for the diagnosis of patients with scrub typhus

Effect of clarithromycin on the cell profile of bronchoalveolar lavage fluid in mice with neutrophil-predominant lung disease Efeito da claritromicina na celularidade do lavado broncoalveolar em camundongos com doença pulmonar neutrofílica induzida

OBJECTIVE: Macrolide antibiotics have anti-inflammatory properties in lung diseases. The aim of this study was to investigate the effect of clarithromycin in pulmonary cellular inflammatory response in mice. METHOD: Eight adult Swiss mice were studied. All animals received an intranasal challenge (80 µL) with dead Pseudomonas aeruginosa (1.0 x 10(12) CFU/mL). Bronchoalveolar lavage was performed 2 days later, with total cell count and differential cell analysis. The study group (n = 4) received clarithromycin treatment (50 mg/kg/day, intraperitoneal) for 5 days. Treatment was initiated 2 days before intranasal challenge. RESULTS: There was no significant difference in total cell count between the groups (mean: 2.0 x 10(6) and 1.3 x 10(6), respectively). In both groups, there was a predominance of neutrophils. However, the study group had a higher percentage of lymphocytes in the bronchoalveolar lavage than the control group (median of 19% vs 2.5%, P = .029). CONCLUSION: Clarithromycin alters the cytological pattern of bronchoalveolar lavage of Swiss mice with neutrophil pulmonary inflammation, significantly increasing the percentage of lymphocytes.<br>OBJETIVO: Os antibióticos macrolídeos podem apresentar um efeito antiinflamatório em doenças pulmonares. O objetivo deste estudo é investigar o efeito da claritromicina na resposta inflamatória celular pulmonar em camundongos Swiss. MÉTODO: Foram utilizados 8 camundongos Swiss adultos (6-8 semanas). Todos os animais receberam um desafio intranasal (80 µL) com Pseudomonas aeruginosa mortas (1 x 10(12) UFC/mL). Dois dias após o desafio, foi realizado lavado broncoalveolar (LBA) com contagem total de células (CTC) e exame citológico diferencial. O grupo em estudo (n=4) recebeu tratamento com claritromicina (50mg/kg/dia, intraperitoneal) por 5 dias, sendo iniciado o tratamento 2 dias antes do desafio intranasal. O grupo controle (n=4) não recebeu tratamento com claritromicina. RESULTADOS: Não houve diferença significativa na CTC entre os grupos (média de 2x10(6) e 1,3x10(6), respectivamente). Em ambos os grupos, houve predomínio absoluto de neutrófilos. Contudo, o grupo tratado com claritromicina, apresentou um número percentual significativamente maior de linfócitos no LBA (mediana de 2,5% vs 19%, p=0,029). CONCLUSÃO: O uso de claritromicina altera o exame citológico diferencial do lavado bronco-alveolar de camundongos Swiss com inflamação pulmonar neutrofílica, aumentando significativamente o número percentual de linfócitos

Development of an experimental model of neutrophilic pulmonary response induction in mice

BACKGROUND: Several lung diseases are characterized by a predominantly neutrophilic inflammation. A better understanding of the mechanisms of action of some drugs on the airway inflammation of such diseases may bring advances to the treatment. OBJECTIVE: To develop a method to induce pulmonary neutrophilic response in mice, without active infection. METHODS: Eight adult Swiss mice were used. The study group (n = 4) received an intranasal challenge with 1 x 10(12) CFU/ml of Pseudomonas aeruginosa (Psa), frozen to death. The control group (n = 4) received an intranasal challenge with saline solution. Two days after the intranasal challenge, a bron­choalveolar lavage (BAL) was performed with total cell and differential cellularity counts. RESULTS: The total cell count was significantly higher in the group with Psa, as compared to the control group (median of 1.17 x 10(6) and 0.08 x 10(6), respectively, p = 0.029). In addition to this, an absolute predominance of neutrophils was found in the differential cellularity of the mice that had received the Psa challenge. CONCLUSIONS: The model of inducing a neutrophilic pulmonary disease using frost-dead bacteria was successfully developed. This neutrophilic inflammatory response induction model in Swiss mice lungs may be an important tool for testing the anti-inflammatory effect of some antimicrobial drugs on the inflammation of the lower airways

Perfil de sujeitos de pesquisa clínica em um centro ambulatorial independente Profile of clinical research subjects in an independent outpatient center

Este artigo tem como objetivos avaliar a qualidade de atendimento de um centro de pesquisa clínica e o entendimento do termo de consentimento informado (TCLE); determinar os motivos da participação e detalhar níveis socioeconômicos. Foi feito um estudo transversal em centro de pesquisa ambulatorial, através de questionário auto-explicativo. Dos cem questionários avaliados, todos os sujeitos de pesquisa consideraram o centro como ótimo (86%) ou bom (9%). A quase totalidade foi bem informada do conteúdo do TCLE e o conhecimento do direito "confidencialidade", comum a todos os TCLEs, foi seis vezes maior que " acesso aos dados", que não faz parte. Os principais motivos para participarem foram para "saber mais sobre a sua saúde" (59%) e para "beneficiar outras pessoas no futuro" (47%). A principal faixa de renda salarial dos participantes foi entre dois e cinco salários mínimos (48%) e a maioria (66%) concluiu pelo menos até a 4º série do ensino fundamental. A população possui o mesmo perfil econômico do Rio de Janeiro, nível de escolaridade suficiente para assinar e compreender o que está assinando, conhecendo não só a existência do TCLE, mas demonstrando conhecer seu conteúdo. O motivo principal para participação é para autobenefício e por atitude altruísta.<br>This paper assesses the quality of assistance in a clinical trial outpatient center as well as the patients´understanding of the informed consent (IC); determine the reasons why they participate and detail socio-economic levels. A cross-sectional study was adopted in a clinical trial outpatient center using a self-explanatory questionnaire. All 100 respondents considered the assistance at the center excellent (86%) or good (9%). Almost all of them were well informed about the content of the IC. Their knowledge about the right to "confidentiality", present in all ICs, was 6 times higher than their knowledge about their right to "access the results", generally not included in the IC. The main reasons for participating were "to know more about ones health" (59%) and to "to benefit other people in the future" (47%). The participants´ income varied from 3 to 5 minimum wages (48%) and most (66%) concluded at least the 4th grade of basic education in Brazil. The subjects showed the economical characteristics of the average population of Rio de Janeiro. Their level of education allowed them to sign and to understand what they were signing. They were aware of the existence of the IC and its content. The main reason for participating was for one´s own benefit and for the benefit of others