Elucidando a imunovigilância e imunoedição tumoral: uma revisão abrangente / Elucidating tumor immunosurveillance and immunoediting: a comprehensive review

A ação do sistema imunológico contra as enfermidades neoplásicas tem se tornado uma das principais fontes de pesquisa na atualidade. As vias biológicas desse sistema são conhecidas por contribuir na limitação da progressão e na eliminação do tumor, e são delineadas por conceitos e mecanismos de imunovigilância e imunoedição. A imunovigilância é considerada o processo pelo qual o sistema imunológico reconhece e inibe o processo neoplásico. O conceito de imunoedição tem origem no sentido de que o sistema imune é capaz de moldar o perfil antigênico do tumor devido à pressão seletiva, baseada nas etapas de eliminação, equilíbrio e evasão tumoral. A resposta imunológica ocorre contra antígenos tumorais e modificações do microambiente tumoral, envolvendo diferentes componentes do sistema imune inato, como células T, células natural Killer, linfócitos B e macrófagos. Nesse sentido, conhecer esses conceitos e compreender seus respectivos mecanismos torna-se essencial na investigação de novas estratégias de prevenção e combate ao câncer. Dessa forma, esta revisão apresenta aspectos históricos e definições de imunovigilância e imunoedição tumoral, com ênfase em sua importância e aplicabilidade, assim como aos diferentes métodos utilizados em imunoterapia.

The action of the immune system against neoplastic diseases has become one of the main sources of research. The biological pathways of this system are known to contribute in limiting the progression and elimination of the tumor, and are delineated by concepts and mechanisms of immunosurveillance and immunoediting. Immunosurveillance is considered the process by which the immune system recognizes and inhibits the neoplastic process. The concept of immunoediting arises in the sense that immune system is able to shape the antigenic profile of the tumor due to selective pressure, based on the stages of tumor elimination, balance and evasion. The immune response occurs against tumor antigens and changes in the tumor microenvironment, involving different components of the innate immune system, such as T cells, natural Killer cells, B lymphocytes and macrophages. In this sense, knowing these concepts and understanding their respective mechanisms becomes essential in the investigation of new strategies for cancer prevention and cure. Thus, this review presents historical aspects and definitions of immunosurveillance and tumor immunoediting, with emphasis on its importance and applicability, such as on the different methods used in immunotherapy.

Effects of different levels of dietary crude protein and threonine on performance, humoral immune responses and intestinal morphology of broiler chicks

The present study aimed at investigating the effects of different dietary crude protein (CP) and threonine (Thr) levels on the performance, immune responses and jejunal morphology of broiler chicks. A total of 432 broiler chicks were randomly assigned to a 3×3 factorial arrangement of treatments including three different CP dietary levels (90, 95, and 100% of Ross 308 recommendations) and Thr (100, 110, and 120% of Ross specifications) dietary levels. Performance parameters were recorded for the starter (1-12 days), grower (13-24 days) and finisher (25-42 days) periods. Birds were subjected to different antigen inoculations to evaluate antibody responses. At day 42 of age, two randomly-selected birds per replicate were slaughtered to measure carcass traits. Although Thr dietary supplementation had no marked effect on Newcastle antibody titers, particularly the supplementation of Thr up to 110% of Ross specifications improved (p 0.05) antibody titers against sheep red blood cells during both primary and secondary responses. Reduction of dietary CP level resulted in significant decrease in villus height (p 0.05) and crypt depth (p 0.01) in jejunal epithelial cells, but the supplementation of low-CP diets with Thr up to 110 and 120% of the recommended values allowed overcoming these changes. Except for the starter period, reducing dietary CP level to 90% of Ross recommendations had no harmful effects on performance parameters; however, the best values were obtained with diets containing 110% Thr. The present results indicate that it is possible to reduce dietary CP level up to 10% after the starter period without any detrimental impact on growth performance, and dietary Thr supplementation up to 110% of Ross values may compensate for low CP-induced growth delay in broiler chicks.

Effects of different levels of dietary crude protein and threonine on performance, humoral immune responses and intestinal morphology of broiler chicks

The present study aimed at investigating the effects of different dietary crude protein (CP) and threonine (Thr) levels on the performance, immune responses and jejunal morphology of broiler chicks. A total of 432 broiler chicks were randomly assigned to a 3×3 factorial arrangement of treatments including three different CP dietary levels (90, 95, and 100% of Ross 308 recommendations) and Thr (100, 110, and 120% of Ross specifications) dietary levels. Performance parameters were recorded for the starter (1-12 days), grower (13-24 days) and finisher (25-42 days) periods. Birds were subjected to different antigen inoculations to evaluate antibody responses. At day 42 of age, two randomly-selected birds per replicate were slaughtered to measure carcass traits. Although Thr dietary supplementation had no marked effect on Newcastle antibody titers, particularly the supplementation of Thr up to 110% of Ross specifications improved (p 0.05) antibody titers against sheep red blood cells during both primary and secondary responses. Reduction of dietary CP level resulted in significant decrease in villus height (p 0.05) and crypt depth (p 0.01) in jejunal epithelial cells, but the supplementation of low-CP diets with Thr up to 110 and 120% of the recommended values allowed overcoming these changes. Except for the starter period, reducing dietary CP level to 90% of Ross recommendations had no harmful effects on performance parameters; however, the best values were obtained with diets containing 110% Thr. The present results indicate that it is possible to reduce dietary CP level up to 10% after the starter period without any detrimental impact on growth performance, and dietary Thr supplementation up to 110% of Ross values may compensate for low CP-induced growth delay in broiler chicks.(AU)

Effects of different levels of dietary crude protein and threonine on performance, humoral immune responses and intestinal morphology of broiler chicks

The present study aimed at investigating the effects of different dietary crude protein (CP) and threonine (Thr) levels on the performance, immune responses and jejunal morphology of broiler chicks. A total of 432 broiler chicks were randomly assigned to a 3×3 factorial arrangement of treatments including three different CP dietary levels (90, 95, and 100% of Ross 308 recommendations) and Thr (100, 110, and 120% of Ross specifications) dietary levels. Performance parameters were recorded for the starter (1-12 days), grower (13-24 days) and finisher (25-42 days) periods. Birds were subjected to different antigen inoculations to evaluate antibody responses. At day 42 of age, two randomly-selected birds per replicate were slaughtered to measure carcass traits. Although Thr dietary supplementation had no marked effect on Newcastle antibody titers, particularly the supplementation of Thr up to 110% of Ross specifications improved (p 0.05) antibody titers against sheep red blood cells during both primary and secondary responses. Reduction of dietary CP level resulted in significant decrease in villus height (p 0.05) and crypt depth (p 0.01) in jejunal epithelial cells, but the supplementation of low-CP diets with Thr up to 110 and 120% of the recommended values allowed overcoming these changes. Except for the starter period, reducing dietary CP level to 90% of Ross recommendations had no harmful effects on performance parameters; however, the best values were obtained with diets containing 110% Thr. The present results indicate that it is possible to reduce dietary CP level up to 10% after the starter period without any detrimental impact on growth performance, and dietary Thr supplementation up to 110% of Ross values may compensate for low CP-induced growth delay in broiler chicks.

The importance of serological assays in diagnosing acute pulmonary histoplasmosis

Histoplasmosis is a systemic mycosis caused by inhalation of Histoplasma capsulatum microconidia. The disease does not normally affect immunocompetent individuals after a single, transient inhalation exposure. However, longer exposure may cause chronic or disseminated acute pulmonary infection. Herein, we report the case of a 24-year-old immunocompetent patient, who presented fever, cough and dyspnea for one month. The chest radiography revealed interstitial infiltrate and diffuse micronodules. The patient reported having had close and prolonged contact with bats. Diagnosis was confirmed by positive double immunodifusion and immunoblotting assays. She was treated with ketoconazole (400 mg) and there was complete resolution of the disease.