Use of ELISA based on NcSRS2 of Neospora caninum expressed in Pichia pastoris for diagnosing neosporosis in sheep and dogs / Utilização de um ELISA baseado em NcSRS2 de Neospora caninum expressa em Pichia pastoris para diagnóstico de neosporose em ovinos e cães

Neosporosis is a disease caused by the protozoon Neospora caninum that leads to significant economic losses in many countries. In the present study, we report on use of the recombinant protein NcSRS2 of N. caninum expressed in Pichia pastoris in an indirect immunoenzymatic assay (ELISA) for diagnosing neosporosis infection in sheep and dogs. We observed that the ELISA test yielded specificity of 94.5% and sensitivity of 100% for sheep and specificity of 93.3% and sensitivity of 100% for dogs. We observed that the sensitivity was higher than shown by the indirect fluorescent antibody test, and this was confirmed by means of Western blot. The results from this study suggest that the recombinant protein expressed in P. pastoris is a suitable antigen for use in immunodiagnosis to detect N. caninum in two important species exposed to this parasitosis.

A neosporose é uma doença causada pelo protozoário Neospora caninum que leva a perdas econômicas importantes em muitos países. No presente estudo, é descrita a utilização da proteína recombinante NcSRS2 de N. caninum expressa em Pichia pastoris em um ensaio imunoenzimático indireto (ELISA) para o diagnóstico de infecção por Neospora em ovelhas e cães. Observou-se, que utilizando-se um ELISA, o teste produziu uma especificidade de 94,5% e uma sensibilidade de 100% para ovinos; e uma especificidade de 93,3% e sensibilidade de 100% para cães. Uma maior sensibilidade foi observada em relação à IFI que foi confirmada por Western blot. Os resultados deste estudo sugerem que a proteína recombinante expressa em P. pastoris é bom antígeno para ser utilizado no diagnóstico imunológico para detectar N. caninum em duas espécies importantes expostas a esta parasitose.

Vascular endothelial growth factor-A enhances indoleamine 2,3-dioxygenase expression by dendritic cells and subsequently impacts lymphocyte proliferation

Dendritic cells (DCs) are antigen (Ag)-presenting cells that activate and stimulate effective immune responses by T cells, but can also act as negative regulators of these responses and thus play important roles in immune regulation. Pro-angiogenic vascular endothelial growth factor (VEGF) has been shown to cause defective DC differentiation and maturation. Previous studies have demonstrated that the addition of VEGF to DC cultures renders these cells weak stimulators of Ag-specific T cells due to the inhibitory effects mediated by VEGF receptor 1 (VEGFR1) and/or VEGFR2 signalling. As the enzyme indoleamine 2,3-dioxygenase (IDO) is recognised as an important negative regulator of immune responses, this study aimed to investigate whether VEGF affects the expression of IDO by DCs and whether VEGF-matured DCs acquire a suppressor phenotype. Our results are the first to demonstrate that VEGF increases the expression and activity of IDO in DCs, which has a suppressive effect on Ag-specific and mitogen-stimulated lymphocyte proliferation. These mechanisms have broad implications for the study of immunological responses and tolerance under conditions as diverse as cancer, graft rejection and autoimmunity.

Immunophenotypic profile of adult acute myeloid leukemia (AML): analysis of 267 cases in Thailand.

Little data exists in Thailand and other Southeast Asian countries regarding the biological characteristics of adult acute myeloid leukemia (AML). In this study, we performed a flow cytometric analysis of 267 Thai adult AML cases to delineate the pattern of leukemic cell surface antigens. Forty-eight cases (18%) were identified as acute promyelocytic leukemia (M3) and 219 cases as non-M3. The most frequent subtype of AML in Thailand was M1/M2 and the least frequent was M7. M3 immunophenotypes were characterized by their unique lack of expression of CD34 and HLA-DR as contrast to the high mean expression of 50% and 70%, respectively, in non-M3. Overall, 60% of cases expressed CD34. Aberrant lymphoid antigens were uniquely seen in specific subtypes of Thai AML, including CD19 (33% of non-M3 vs 23% of M3) and CD2 (12% of M3 vs 2% of non-M3). CD56 was frequently expressed in both M3 and non-M3 while CD16 appeared to be associated with M4/M5 (24% of cases) and CD7 with M1/M2 (21% of cases). Eighty-one percent of non-M3 expressed CD38 while only 53% of M3 did. We found that most Thai adult AML patients were on average 15-20 years younger than those of the West or Japan with only 25% of Thai cases over 60 years of age, although the immunophenotypes were not markedly different. Biological studies of acute leukemia in various countries should help to provide epidemiological clues that play a role in the pathogenesis of leukemia in different geographic regions of the world. Our study represents the largest series of AML ever investigated in the Southeast Asian region.

Enfermedad de Woringer-Kolopp reporte de un caso / Woringer-Kolopp of disease repot of one case

La enfermedad de Woringer-kolopp es un desorden linfoproliferativoclonal de células T, raro, bien definido que afecta la piel; clínicamente benigno pero histológicamente maligno. Se presenta como una placa hiperqueratótica, asintomática caracterizada por un infiltrado de células mononucleares citológicamente atípica. Se reporta el caso de un paciente de 52 años que presentó la enfermedad con características clínicas histopatológicas típicas que fue tratado con radioterapia y quimioterapia con buena evolución

Biochemical analysis of glycophospholipids from wild-type mouse lymphoma cells and from Thy-1 negative mutants which do not add glycolipid-anchored proteins.

Thy-1 is a major glycophospholipid (GPL)-anchored protein found on the surface of neurons, epithelial cells, fibroblasts and murine T-lymphomas. Biochemical studies were undertaken to determine if murine T-lymphomas contain glycolipids which may be on the path of GPL-anchor biosynthesis. Biosynthetic labeling experiments on Thy-1-positive (wild-type) cells followed by battery of chemical and enzymatic diagnostics on the isolated [3H]mannolipids have, for the first time, led to description of a set of glycolipids which have properties consistent with their being GPL-anchor precursors. Using these results as a guide, major differences have been observed upon analysis of the radiolabeled mannolipids of Thy-1-negative mutants from 7 complementation classes, A-C, E, F, H and I. The biosynthetic lesions in anchor synthesis have been identified in some of the mutants.

Growth curves of Leishmania brasiliensis brasiliensis promastigotes and surface antigen expression before and after adaptation to schneider's Drosophila medium as assessed by anti-leishmania human sera

Promastigotas de Leismania braziliensis (MHom/BR/75/M2903) foram cultivadas em meio de Schneider de cultura de drosófilas. em um tipo de experiência as formas promastigotas já haviam sido previamente adaptadas ao meio por passagens consecutivas enquanto que no segundo as promastigotas foram cultivadas em meio bifásico e depois transferidas para o meio líquido. O crescimento foi mais abundante nas células já adaptadas ao meio de cultura; células degeneradas e mortas em pequenos números, estavam presentes desde o dia 5 para promastigotas adaptadas ao meio líqüido e desde o dia 3 para células recentemente adaptadas. A síntese de antígenos de superfície diferiu de acordo com o modo como as células eram cultivadas, como verificado pelo título de 5 soros de leishmaniose mucocutânea. O melhor período para a preparaçäo de antígenos de imunofluorescência foi considerado o dia 5 para promastigotas adaptadas ao meio de cultivo e o dia 3 para células recentemente adaptadas