Naturally presented HLA class I-restricted epitopes from the neurotrophic factor S100-? are targets of the autoimmune response in type 1 diabetes

Type 1 diabetes (T1D) results from the destruction of pancreatic beta-cells by the immune system, and CD8(+) T lymphocytes are critical actors in this autoimmune response. Pancreatic islets are surrounded by a mesh of nervous cells, the peri-insular Schwann cells, which are also targeted by autoreactive T lymphocytes and express specific antigens, such as the neurotrophic factor S100-beta. Previous work has shown increased proliferative responses to whole S100-beta in both human T1D patients and the nonobese diabetic (NOD) mouse model. We describe for the first time naturally processed and presented epitopes (NPPEs) presented by class I human leukocyte antigen-A*02:01 (A2.1) molecules derived from S100-beta. These NPPEs triggered IFN-gamma responses more frequently in both newly diagnosed and long-term T1D patients compared with healthy donors. Furthermore, the same NPPEs are recognized during the autoimmune response leading to diabetes in A2.1-transgenic NOD mice as early as 4 wk of age. Interestingly, when these NPPEs are used to prevent diabetes in this animal model, an acceleration of the disease is observed together with an exacerbation in insulitis and an increase in S100-beta-specific cytotoxicity in vaccinated animals. Whether these can be used in diabetes prevention needs to be carefully evaluated in animal models before use in future clinical assays.-Calvino-Sampedro, C., Gomez-Tourino, I., Cordero, O. J., Reche, P. A., Gomez-Perosanz, M., Sanchez-Trincado, J. L., Rodriguez, M. A., Sueiro, A. M., Vinuela, J. E., Calvino, R. V. Naturally presented HLA class I-restricted epitopes from the neurotrophic factor S100-beta are targets of the autoimmune response in type 1 diabetes

SISTEMA INTENSIVO X EXTENSIVO NA CRIAÇÃO DE GADO DE CORTE

A pecuária mundial está em constante desenvolvimento, e o Brasil ocupa o segundo lugar no ranking mundial na exportação de carne bovina (USDA, 2016). Posição essa que têm levado os produtores a administrar suas fazendas como empresas. No presente trabalho, foram analisados dois sistemas de produção mais adotados na pecuária brasileira: o extensivo e o intensivo, conhecidos popularmente como a pasto e confinamento. A partir dos aspectos administrativos e agropecuários envolvidos compararam-se três fazendas no sul de Minas Gerais. Essa pesquisa ocorreu a campo, realizando-se com o produtor um questionário contendo todas as variáveis presentes no sistema de produção. Adaptou-se a metodologia de Lopes e Carvalho (2000), com tabelas pré-elaboradas para direcionar os cálculos de custo operacional total, custos fixos e variáveis. Utilizou-se a cotação atual da arroba de carne bovina para calcular a remuneração do capital investido e ponto de nivelamento operacional, chegando-se ao final na demonstração do lucro ou prejuízo da atividade em cada fazenda. Ao final do estudo, percebeu-se que o sistema extensivo foi o que demonstrou rentabilidade, porém isso ocorreu em apenas uma propriedade. Os dois confinamentos analisados mostraram prejuízo final. Assim, o sistema intensivo mostrou-se inviável, tendo como fator prejudicial o custo da alimentação e o alto valor de aquisição dos animais. A criação extensiva apresentou lucro e o melhor custo benefício para o produtor, porém isso ocorreu em apenas uma propriedade. Conclui-se assim, que o resultado será reflexo do conhecimento prévio de mercado e dos fatores que envolvem o custo operacional

Adaptive from Innate: Human IFN-γ+CD4+ T Cells Can Arise Directly from CXCL8-Producing Recent Thymic Emigrants in Babies and Adults.

We recently demonstrated that the major effector function of neonatal CD4+ T cells is to produce CXCL8, a prototypic cytokine of innate immune cells. In this article, we show that CXCL8 expression, prior to proliferation, is common in newly arising T cells (so-called "recent thymic emigrants") in adults, as well as in babies. This effector potential is acquired in the human thymus, prior to TCR signaling, but rather than describing end-stage differentiation, such cells, whether isolated from neonates or adults, can further differentiate into IFN-γ-producing CD4+ T cells. Thus, the temporal transition of host defense from innate to adaptive immunity is unexpectedly mirrored at the cellular level by the capacity of human innate-like CXCL8-producing CD4+ T cells to transition directly into Th1 cells

Peripheral Effects of FAAH Deficiency on Fuel and Energy Homeostasis: Role of Dysregulated Lysine Acetylation

FAAH (fatty acid amide hydrolase), primarily expressed in the liver, hydrolyzes the endocannabinoids fatty acid ethanolamides (FAA). Human FAAH gene mutations are associated with increased body weight and obesity. In our present study, using targeted metabolite and lipid profiling, and new global acetylome profiling methodologies, we examined the role of the liver on fuel and energy homeostasis in whole body FAAH(-/-) mice.FAAH(-/-) mice exhibit altered energy homeostasis demonstrated by decreased oxygen consumption (Indirect calorimetry). FAAH(-/-) mice are hyperinsulinemic and have adipose, skeletal and hepatic insulin resistance as indicated by stable isotope phenotyping (SIPHEN). Fed state skeletal muscle and liver triglyceride levels was increased 2-3 fold, while glycogen was decreased 42% and 57% respectively. Hepatic cholesterol synthesis was decreased 22% in FAAH(-/-) mice. Dysregulated hepatic FAAH(-/-) lysine acetylation was consistent with their metabolite profiling. Fasted to fed increases in hepatic FAAH(-/-) acetyl-CoA (85%, p<0.01) corresponded to similar increases in citrate levels (45%). Altered FAAH(-/-) mitochondrial malate dehydrogenase (MDH2) acetylation, which can affect the malate aspartate shuttle, was consistent with our observation of a 25% decrease in fed malate and aspartate levels. Decreased fasted but not fed dihydroxyacetone-P and glycerol-3-P levels in FAAH(-/-) mice was consistent with a compensating contribution from decreased acetylation of fed FAAH(-/-) aldolase B. Fed FAAH(-/-) alcohol dehydrogenase (ADH) acetylation was also decreased.Whole body FAAH deletion contributes to a pre-diabetic phenotype by mechanisms resulting in impairment of hepatic glucose and lipid metabolism. FAAH(-/-) mice had altered hepatic lysine acetylation, the pattern sharing similarities with acetylation changes reported with chronic alcohol treatment. Dysregulated hepatic lysine acetylation seen with impaired FAA hydrolysis could support the liver's role in fostering the pre-diabetic state, and may reflect part of the mechanism underlying the hepatic effects of endocannabinoids in alcoholic liver disease mouse models