The role of the SLAM-SAP signaling pathway in the modulation of CD4+ T cell responses

The signaling lymphocytic activation molecule (SLAM), present on the surface of hematopoietic cells, can regulate some events of the immune responses. This modulatory action is associated with the capacity of SLAM to interact with an intracytoplasmic adapter, such as SLAM-associated protein (SAP). SLAM is constitutively expressed in most of these cells, is rapidly induced after antigenic or inflammatory stimuli, and participates in the immunological synapse. Defects in the function of the SLAM-SAP pathway contribute to immunological abnormalities, resulting in autoimmune diseases, tumors of the lymphoid tissues and inadequate responses to infectious agents. Initially, the role of SLAM was investigated using an anti-SLAM monoclonal antibody (α-SLAM mAb) identified as an agonist of the SLAM-SAP pathway, which could induce the production of interferon-γ and could redirect the immune response to a T helper 1 (Th1) cell profile. However, in this review we postulate that the SLAM-SAP pathway primarily induces a Th2 response and secondarily suppresses the Th1 response.

Tipificação genética, através da técnica de spoligotyping, de isolados de Mycobacterium bovis em animais abatidos na região metropolitana de Salvador, Bahia, Brasil / Use of spoligotyping for genetic typing of Mycobacterium bovis isolates from slaughtered animals in the metropolitan area of Salvador, Bahia, Brazil

A tuberculose é uma enfermidade infecciosa crônica, que afeta mamíferos e aves e constitui um sério problema de saúde pública e animal. Objetivando realizar um levantamento molecular da enfermidade em bovinos abatidos em matadouros frigoríficos no Estado da Bahia, Brasil, foram analisadas as lesões pulmonares e de linfonodos mediastínicos de 43 carcaças de animais abatidos em três matadouros-frigoríficos localizados na Região Metropolitana de Salvador, Bahia. Sete isolados de Mycobacterium bovis foram identificados, através da técnica do spolygotyping, e discriminados em três diferentes espoligotipos (SB1055, SB0120 e SB0268) descritos no Brasil e em diversas áreas do mundo. Os resultados indicam que o método de diagnóstico utilizado pode contribuir para a criação de uma base de dados para o estudo epidemiológico da tuberculose bovina no Estado da Bahia.

Tuberculosis is an infectious chronic disease that affects mammals and birds and constitutes a serious problem for public and animal health. Pulmonary and mediastinic lymph node lesions of 43 animals slaughtered in 3 slaughterhouses in the metropolitan region of the city of Salvador, Bahia, Brazil, were analyzed with the objective of obtaining a molecular survey of the disease in bovines slaughtered in slaughterhouses in the state. Seven isolates ofMycobacterium bovis were identified through the spoligotyping technique and classified into 3 different spoligotypes (SB1055, SB0120, SB0268), described in Brazil and in many areas worldwide. The results indicate that the diagnostic method utilized may contribute to the creation of a database for the epidemiologic study of bovine tuberculosis in the state of Bahia.

Perfil do câncer gástrico no Hospital das Clínicas da Universidade Federal de Pernambuco / Profile of gastric cancer at the University Hospital of the Federal University of Pernambuco

A partir de um estudo retrospectivo realizado no Serviço de Endoscopia do Hospital das Clínicas-UFPE, em 10.230 exames de endoscopia digestiva alta efetuados nos anos de 91, 92 e 93 foram diagnosticados 60 casos de adenocarcinoma gástrico, resultando em incidência de 0,58 por cento da amostra. Os 60 casos estudados mostram dados rigorosamente semelhantes aos publicados na literatura mundial quanto aos aspectos epidemiológicos (idade e sexo), clínicos (dor em abdome superior, perda de peso, etc.) e localizaçao da lesao (antro e corpo). Por outro lado, encontramos baixíssimo índice de diagnóstico de câncer precoce (1,6 por cento) e elevada incidência do tipo histológico difuso (46 por cento), indiferenciado. Noventa por cento das lesoes eram Bormann III e IV. Esses três fatos podem estar relacionados com baixa suspeiçao em relaçao às lesoes precoces e/ou precursoras ou ainda a comportamento biológico mais agressivo do adenocarcinoma em nossa regiao, incluindo aí fatores ambientais diferenciados quando comparados com outras áreas de elevada incidência.

Evaluation of spleen cell population and effect of splenectomy on granuloma modulation in BALB/c mice infected with Schistosoma mansoni

A kinetic study of the cells present in the spleen of BALB/c mice infected with Schistosoma mansoni was carried out. The lymphocytes were evaluated phenotypically with monoclonal antibodies and the effect of splenectomy on the modulation of periovular granuloma was also investigated. The infected mice had proportional increases in the numbers of neutophils, plasma cells, macrophages and eosinophils in the spleen. The largest number of neutrophil, plasma cells and macrophage were found between the 8th and the 12th week of infection, while the amount of eosinophils were higher later on, around the 20th week. The lymphocytes phenotipically characterized as Thy 1.2, Lyt 1.2 (CD4) increased mildly in proportional numbers. However, the percentage of lymphocytes with the Lyt 2.2 (CD8) phenotype, which is characteristic of supressor and cytotoxic T cells, increased significantly with the progress of the disease. The numbers of B lymphocytes, which comprise 50% of the mononuclear cells present in the spleen, increased significantly till the 16th week they began to decrease. The mean diameters of periovular granulomas were comparatively similar in both experimental groups (splenectomized and non-splenectomized mice). However, the evolutive types of granuloma (exudative, intermediate and fibrous) in splenectomized mice were proprtionally different from those of non splenectomized mice in the 16th and 24th week of infection. It is inferred that lymphonodes or other secondary lymphoide organs, in the abscence of the spleen, assume a modulating action on periovular granulomas, although the evolution of the granulomas is somehow delayed in splenectomized mice

Carcinoma verrucoso da vulva. / Verrucous carcinoma of the vulva

Sao relatados tres casos de carcinoma verrucoso envolvendo o epitelio vulvar. Eles representam uma variante rara do carcinoma epidermoide, localmente invasiva e radiorresistente. A semelhanca dessa neoplasia com o condiloma torna dificil o diagnostico