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Introdução. A neurodegeneração progressiva e irreversível da doença de Alzheimer é uma das principais formas clínicas da doença, ocasionando perda gradual da memória, raciocínio, compreensão, linguagem, aprendizagem e dificuldade na realização de tarefas do dia a dia, entre outros. A neurodegeneração gerada por esta doença é causada por mutações nos genes relacionados à síntese das proteínas beta-amiloide e Tau em várias regiões do cérebro associados com a resposta imune, levando a quadros inflamatórios e degenerativos. Objetivo. Compreender qual a influência dos fatores genéticos e imunológicos no desenvolvimento e agravamento do Alzheimer. Método. Foi realizada uma revisão de literatura por meio da busca de artigos na plataforma Pubmed com os descritores: Alzheimer, APOE, micróglia, e resposta imunológica. Foram selecionados trabalhos publicados entre os anos 2011 a 2021, sendo incluídos artigos de revisão, casos clínicos, ensaios clínicos, e meta-análises totalizando no final 18 artigos selecionados. Resultados. Os principais genes mutados envolvidos na imunomodulação e que contribuem na neuroinflamação são: APOE, TREM2, MAPT e APP. Estudos mostram que estes genes quando mutados são os indutores do acúmulo de proteína beta-amiloide e agregados fibrilares de proteína Tau no tecido nervoso. Conclução. Mutações em genes presentes principalmente nas micróglias, astrócitos e neurônios estão relacionados à principal causa do Alzheimer. No entanto, mais estudos são necessários para maior compreensão das mutações em genes específicos e sua interferência na resposta imune associada à neuroinflamação e consequente demência no quadro de Alzheimer.

Dehydroepiandrosterone (DHEA) is a steroid hormone secreted by the adrenal glands, gonads and brain. It is a precursor to sex hormones and also is known to have immune modulatory activity. However, little is known about the relationship between DHEA and neutrophils and thus our study evaluates the influence of DHEA in the effector functions of neutrophils. Human neutrophils were treated in vitro with DHEA and further infected with Salmonella enterica serovar Typhimurium. The treatment of neutrophils with 0.01 μM of DHEA increased the phagocytosis of Salmonella independent of TLR4 as the treatment did not modulate the TLR4 expression. Additionally, DHEA caused a decrease in ROS (reactive oxygen species) production and did not influence the formation of the neutrophil extracellular trap (NET). Steroid treated neutrophils, infected or stimulated with LPS (lipopolysaccharide), showed reduced production of IL-8, compared to untreated cells. Also, the protein levels of p-NFκB were decreased in neutrophils treated with DHEA, and this reduction could explain the reduced levels of IL-8. These results led us to conclude that the steroid hormone DHEA has important modulatory functions in neutrophils.

The HIV/AIDS pandemic still represents an important global health issue. There is no sterilizing cure, therefore a continuous treatment is necessary, which caused the emerged idea of HIV as a chronic inflammatory disease that may also affect healthy aging. Considering that the activation profile of some innate cells such as natural killer cells has previously been associated to HIV progression, it remains to be better defined this activation status of NK cells considering the time of HIV infection. In this study, we characterized NK cell phenotype and function during acute and chronic HIV infection and also investigated markers of immunosenescence in these cells. Our results showed that chronic infected patients remained with elevated levels of some plasma inflammatory molecules (IP-10, sCD14) and a concurrent expansion of the non-functional NK cell subset (CD3-CD56-CD16+). NK cells from the chronic infected group displayed an activated profile with higher levels of cytokines and chemokines production (TNF-α, IL-12, IFN-α2, IFN-γ, IL-6, RANTES, MCP-1, IL-10, IL-4 and IL-5). The production of these molecules was positively correlated to the time of infection. Moreover, we noted a possible association of higher global DNA methylation frequency of NK cells in two HIV patients in the advanced stage of disease. Chronic infected patients also showed a trend towards higher production of reactive oxygen species by their NK cells which altogether suggest the evolution of these cells to a senescent state that might be further evaluated.

Viral hepatitis, syphilis, HIV, and tuberculosis infections in prisons have been identified globally as a public health problem. Tuberculosis (TB) and viral hepatitis co-infection may increase the risk of anti-tuberculosis treatment-induced hepatotoxicity, leading to the frequent cause of discontinuation of the first-line anti-tuberculosis drugs. Therefore, the aim of this cross-sectional study was to investigate the epidemiological features of HCV, HBV, syphilis and HIV infections among bacteriologically confirmed tuberculosis prisoners in Campo Grande (MS), Central Brazil. The participants who agreed to participate (n = 279) were interviewed and tested for the presence of active or current HCV, HBV, syphilis and HIV infections. The prevalence of HCV exposure was 4.7% (13/279; 95% CI 2.2-7.1). HCV RNA was detected in 84.6% (11/13) of anti-HCV positive samples. Out of 279 participants, 19 (6.8%; 95% CI 4.4-10.4) were HIV co-infected, 1.4% (4/279, 95% CI 0.5-3.8) had chronic hepatitis B virus (HBsAg positive) and 9.3% (26/279, 95% CI 6.4-13.4) had serological marker of exposure to hepatitis B virus (total anti-HBc positive). The prevalence of lifetime syphilis infection (anti-T. pallidum positive) was 10% (28/279, 95% CI 7.0-14.2) and active syphilis (VDRL ≥ 1/8 titre) was 5% (14/279, 95% CI 2.9-8.3). The prevalence of TB/HCV co-infection among prisoners with HIV (15.8%) was higher than among HIV-non-infected prisoners (3.8%; P

Annona muricata Linn, commonly known as graviola, is one of the most popular plants used in Brazil for weight loss. The aim of this study is to evaluate the therapeutic effects of three different doses (50 mg/kg, 100 mg/kg, and 150 mg/kg) of aqueous graviola leaf extract (AGE) supplemented by oral gavage, on obese C57BL/6 mice. Food intake, body weight, an oral glucose tolerance test (OGTT), an insulin sensitivity test, quantification of adipose tissue cytokines, weight of fat pads, and serum biochemical and histological analyses of the liver, pancreas, and epididymal adipose tissue were measured. AGE had an anti-inflammatory effect by increasing IL-10 at doses of 50 and 100 mg/kg. Regarding the cholesterol profile, there was a significant decrease in LDL-cholesterol levels in the AGE 150 group, and VLDL-cholesterol and triglycerides in the AGE 100 and 150 groups. There was an increase in HDL cholesterol in the AGE 150 group. The extract was able to reduce the adipocyte area of the epididymal adipose tissue in the AGE 100 and 150 groups. According to the histological analysis of the liver and pancreas, no significant difference was found among the groups. There were no significant effects of AGE on OGTT and serum fasting glucose concentration. However, the extract was effective in improving glucose tolerance in the AGE 150 group.

Annona muricata Linn, commonly known as graviola, is one of the most popular plants used in Brazil for weight loss. The aim of this study is to evaluate the therapeutic effects of three different doses (50 mg/kg, 100 mg/kg, and 150 mg/kg) of aqueous graviola leaf extract (AGE) supplemented by oral gavage, on obese C57BL/6 mice. Food intake, body weight, an oral glucose tolerance test (OGTT), an insulin sensitivity test, quantification of adipose tissue cytokines, weight of fat pads, and serum biochemical and histological analyses of the liver, pancreas, and epididymal adipose tissue were measured. AGE had an anti-inflammatory effect by increasing IL-10 at doses of 50 and 100 mg/kg. Regarding the cholesterol profile, there was a significant decrease in LDL-cholesterol levels in the AGE 150 group, and VLDL-cholesterol and triglycerides in the AGE 100 and 150 groups. There was an increase in HDL cholesterol in the AGE 150 group. The extract was able to reduce the adipocyte area of the epididymal adipose tissue in the AGE 100 and 150 groups. According to the histological analysis of the liver and pancreas, no significant difference was found among the groups. There were no significant effects of AGE on OGTT and serum fasting glucose concentration. However, the extract was effective in improving glucose tolerance in the AGE 150 group.

Objectives: Three decades after HIV recognition and its association with AIDS development, many advances have emerged – especially related to prevention and treatment. Undoubtedly, the development of Highly Active Antiretroviral Therapy (HAART) dramatically changed the future of the syndrome that we know today. In the present study, we evaluate the impact of Highly Active Antiretroviral Therapy on macrophage function and its relevance to HIV pathogenesis. Methods: PBMCs were isolated from blood samples and monocytes (CD14+ cells) were purified. Monocyte-Derived Macrophages (MDMs) were activated on classical (MGM-CSF+IFN-γ) or alternative (MIL-4+IL13) patterns using human recombinant cytokines for six days. After this period, Monocyte-Derived Macrophages were stimulated with TLR2/Dectin-1 or TLR4 agonists and we evaluated the influence of HIV-1 infection and Highly Active Antiretroviral Therapy on the release of cytokines/chemokines by macrophages. Results: The data were obtained using Monocyte-Derived Macrophages derived from HIV naïve or from patients on regular Highly Active Antiretroviral Therapy. Classically Monocyte-Derived Macrophages obtained from HIV-1 infected patients on Highly Active Antiretroviral Therapy released higher levels of IL-6 and IL-12 even without PAMPs stimuli when compared to control group. On the other hand, alternative Monocyte-Derived Macrophages derived from HIV-1 infected patients on Highly Active Antiretroviral Therapy released lower levels of IL-6, IL-10, TNF-α, IP-10 and RANTES after LPS stimuli when compared to control group. Furthermore, healthy individuals have a complex network of cytokines/chemokines released by Monocyte-Derived Macrophages after PAMP stimuli, which was deeply affected in MDMs obtained from naïve HIV-1 infected patients and only partially restored in MDMs derived from HIV-1 infected patients even on regular Highly Active Antiretroviral Therapy. Conclusion: Our therapy protocols were not effective in restoring the functional alterations induced by HIV, especially those found on macrophages. These findings indicate that we still need to develop new approaches and improve the current therapy protocols, focusing on the reestablishment of cellular functions and prevention/treatment of opportunistic infections. Keywords: HIV-1, Innate immune response, HAART, Macrophages

Although much research has been done related to biomarker discovery for tuberculosis infection, a set of biomarkers that can discriminate between active and latent TB diseases remains elusive. In the current study we correlate clinical aspects of TB disease with changes in the immune response as determined by biomarkers detected in plasma. Our study measured 18 molecules in human plasma in 17 patients with active disease (APTB), 14 individuals with latent tuberculosis infection (LTBI) and 16 uninfected controls (CTRL). We found that active tuberculosis patients have increased plasma levels of IL-6, IP-10, TNF-α, sCD163 and sCD14. Statistical analysis of these biomarkers indicated that simultaneous measurement of sCD14 and IL-6 was able to diagnose active tuberculosis infection with 83% accuracy. We also demonstrated that TNF-α and sCD163 were correlated with tuberculosis severity. We showed that the simultaneous detection of both plasma sCD14 and IL-6 is a promising diagnostic approach to identify APTB, and further, measurement of TNF-α and sCD163 can identify the most severe cases of tuberculosis.

Innate immune cells play a critical role during the onset of HIV infection and remain active until the final events that characterize AIDS. The viral impact on innate immune cell response may be a result of direct infection or indirect modulation, and each cell type responds in a specific manner to HIV. During HIV infection, the immune system works in a dynamic way, where innate and adaptive cells contribute with each other stimulating their function and modulating phenotypes and consequently infection resolution. Understanding the alterations in the cell populations induced by the virus is pivotal and can help to combat HIV at the time of infection and above all, to prevent the establishment of viral reservoirs. In this review, we will describe the frequency and the subtypes of infected cells such as of monocytes, DCs, neutrophils, eosinophils, mast cells/basophils, NK cells, NKT cells and γδ T cells, and we discuss the possibility of cell-targeting strategies. Our aim is to consolidate the existing knowledge of the interaction between HIV and cells that constitute the innate immune response.

This study was financed in part by the Coordenac??o de Aperfeic?oamento de Pessoal de N??vel Superior - Brasil (CAPES) - Finance Code 001. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia. Ananindeua, PA, Brasil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Estudos Costeiros. Grupo de Estudo e Pesquisa em Popula??es Vulner?veis. Bragan?a, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazil. Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Programa de P?s-gradua??o em Biologia de Agentes Infecciosos e Parasit?rios. Bel?m, PA, Brazil / Universidade Federal do Par?. Instituto de Ci?ncias Biol?gicas. Laborat?rio de Virologia. Bel?m, PA, Brazi Introduction - Human pegivirus 1 (HPgV-1) is a single-stranded, positive-sense RNA virus belonging to the Flaviviridae family with limited cause-effect evidence of the causation of human diseases. However, studies have shown a potential beneficial impact of HPgV-1 coinfection in HIV disease progression. Human T lymphotropic virus-1 (HTLV-1) is a retrovirus known for causing diseases, especially in muscle and white blood cells, in approximately 5% of patients. Thus, this study aimed to investigate the potential effects of an HPgV-1 infection in patients carrying HTLV-1 in the state of Par? in the North Region of Brazil. Methods - A group of HTLV-1 carriers was compared to healthy controls. Blood samples were collected, data from medical regards were collected, and a questionnaire was administered. HPgV-1 and HTLV-1 positivity was determined by quantitative polymerase chain reaction (qRT-PCR). The data were analyzed to correlate the effects of HPgV-1 coinfection in HTLV-1 carriers. Results - A total of 158 samples were included in the study: 74 HTLV-1-positive patients (46,8%) and 84 healthy controls (53,2%). The overall HPgV-1 positivity rate was 7.6% (12/158), resulting in a prevalence of 5.4% (4/74) and 9.5% (8/84) in HTLV-1 carriers and healthy controls, respectively. No significant differences were found when comparing any clinical or demographic data between groups. Conclusion - This study indicated that the prevalence of HPgV-1 infection is low in HTLV-1 carriers in Bel?m, Par?, and probably does not alter the clinical course of HTLV-1 infection, however, further studies are still needed.

Monocytes are key cells in the immune dysregulation observed during human immunodeficiency virus (HIV) infection. The events that take place specifically in monocytes may contribute to the systemic immune dysfunction characterized by excessive immune activation in infected individuals, which directly correlates with pathogenesis and progression of the disease. Here, we investigated the immune dysfunction in monocytes from untreated and treated HIV + patients and associated these findings with epigenetic changes. Monocytes from HIV patients showed dysfunctional ability of phagocytosis and killing, and exhibited dysregulated cytokines and reactive oxygen species production after M. tuberculosis challenge in vitro. In addition, we showed that the expression of enzymes responsible for epigenetic changes was altered during HIV infection and was more prominent in patients that had high levels of soluble CD163 (sCD163), a newly identified plasmatic HIV progression biomarker. Among the enzymes, histone acetyltransferase 1 (HAT1) was the best epigenetic biomarker correlated with HIV - sCD163 high patients. In conclusion, we confirmed that HIV impairs effector functions of monocytes and these alterations are associated with epigenetic changes that once identified could be used as targets in therapies aiming the reduction of the systemic activation state found in HIV patients.

The human immunodeficiency virus (HIV) is responsible for more than 2 million new infections per year and opportunistic infections such as Salmonella spp. Gastroenteritis is an important cause of mortality and morbidity in developing countries. Monocytes and macrophages play a critical role in the innate immune response against bacterial infections. However during HIV infection the virus can infect these cells and although they are more resistant to the cytopathic effects, they represent an important viral reservoir in these patients. Our aim was to evaluate the monocyte functions from HIV-1 infected patients after in vitro exposition to Salmonella Enteritidis. Our results suggest impairment of monocytes phagocytic and microbicidal activity in HIV-1 non-treated patients, which was more evident in women, if compared with men. Moreover, monocytes from HIV-1 infected and non-treated patients after stimulation with the bacteria, produced more pro-inflammatory cytokines than monocytes from HIV-treated patients, suggesting that HIV-1 infected patients have their functions unbalanced, once in the presence of an opportunistic infection in vitro.

The human immunodeficiency virus (HIV) is responsible for more than 2 million new infections per year and opportunistic infections such as Salmonella spp. Gastroenteritis is an important cause of mortality and morbidity in developing countries. Monocytes and macrophages play a critical role in the innate immune response against bacterial infections. However during HIV infection the virus can infect these cells and although they are more resistant to the cytopathic effects, they represent an important viral reservoir in these patients. Our aim was to evaluate the monocyte functions from HIV-1 infected patients after in vitro exposition to Salmonella Enteritidis. Our results suggest impairment of monocytes phagocytic and microbicidal activity in HIV-1 non-treated patients, which was more evident in women, if compared with men. Moreover, monocytes from HIV-1 infected and non-treated patients after stimulation with the bacteria, produced more pro-inflammatory cytokines than monocytes from HIV-treated patients, suggesting that HIV-1 infected patients have their functions unbalanced, once in the presence of an opportunistic infection in vitro.

The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL) in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs). The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs) and 18 healthy controls (HCs) in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host genetic background to better understand the low frequency of HAM/TSP in Japanese HTLV-1-infected individuals.

Tuberculosis (TB) is a major public health concern worldwide; however the factors that account for resistance or susceptibility to disease are not completely understood. Although some studies suggest that the differential expression of miRNAs in peripheral blood of TB patients could be useful as biomarkers of active disease, their involvement during the inflammatory process in lungs of infected individuals is unknown. Here, we evaluated the global expression of miRNAs in the lungs of mice experimentally infected with Mycobacterium tuberculosis on 30 and 60 days post-infection. We observed that several miRNAs were differentially expressed compared to uninfected mice. Furthermore, we verified that the expression of miR-135b, miR-21, miR-155, miR-146a, and miR-146b was significantly altered in distinct leukocyte subsets isolated from lungs of infected mice, while genes potentially targeted by those miRNAs were associated with a diversity of immune related molecular pathways. Importantly, we validated the inhibition of Pellino 1 expression by miR-135b in vitro. Overall, this study contributes to the understanding of the dynamics of miRNA expression in lungs during experimental TB and adds further perspectives into the role of miRNAs on the regulation of immune processes such as leukocyte activation.

Background:Successful highly active antiretroviral therapy (HAART) has changed the outcome of AIDS patients worldwide because the complete suppression of viremia improves health and prolongs life expectancy of HIV-1+ patients. However, little attention has been given to the immunological profile of patients under distinct HAART regimens. This work aimed to investigate the differences in the immunological pattern of HIV-1+ patients under the first- or second-line HAART in Brazil. Methods:CD4+ T cell counts, Viral load, and plasma concentration of sCD14, sCD163, MCP-1, RANTES, IP-10, IL-1β, IL-6, TNF-α, IL-12, IFN-α, IFN-γ, IL-4, IL-5, and IL-10 were assessed for immunological characterization of the following clinical groups: Non-infected individuals (NI; n = 66), HIV-1+ untreated (HIV; n = 46), HIV-1+ treated with first-line HAART (HAART 1; n = 15); and HIV-1+ treated with second-line HAART (HAART 2; n = 15). Results:We found that the immunological biosignature pattern of HAART 1 is similar to that of NI individuals, especially in patients presenting slow progression of the disease, while patients under HAART 2 remain in a moderate inflammatory state, which is similar to that of untreated HIV patients pattern. Network correlations revealed that differences in IP-10, TNF-α, IL-6, IFN-α, and IL-10 interactions were primordial in HIV disease and treatment. Heat map and decision tree analysis identified that IP-10>TNF-α>IFN-α were the best respective HAART segregation biomarkers. Conclusion:HIV patients in different HAART regimens develop distinct immunological biosignature, introducing a novel perspective into disease outcome and potential new therapies that consider HAART patients as a heterogeneous group.

Objectives Although TB immunotherapy improves the results of conventional drug treatment, the effects of combining chemotherapy and immunotherapy have never been systematically evaluated. We used a comprehensive lung transcriptome analysis to directly compare the activity of combined chemotherapy and immunotherapy with that of single treatments in a mouse model of TB. Methods Mycobacterium tuberculosis-infected mice in the chronic phase of the disease (day 30) received: (i) isoniazid and rifampicin (drugs) daily for 30 days; (ii) DNA immunotherapy (DNA), consisting of four 100 μg injections at 10 day intervals; (iii) both therapies (DNA + drugs); or (iv) saline. The effects were evaluated 10 days after the end of treatment (day 70 post-infection). Results In all groups a systemic reduction in the load of bacilli was observed, bacilli became undetectable in the drugs and DNA + drugs groups, but the whole lung transcriptome analysis showed 867 genes exclusively modulated by the DNA + drugs combination. Gene enrichment analysis indicated that DNA + drugs treatment provided synergistic effects, including the down-regulation of proinflammatory cytokines and mediators of fibrosis, as confirmed by real-time PCR, ELISA, histopathology and hydroxyproline assay. Conclusions Our results provide a molecular basis for the advantages of TB treatment using combined chemotherapy and DNA immunotherapy and demonstrate the synergistic effects obtained with this strategy.

Despite substantial efforts in recent years toward the development of new vaccines and drugs against tuberculosis (TB), success has remained elusive. Immunotherapy of TB with mycobacterial Hsp65 as a DNA vaccine (DNA-hsp65) results in a reduction of systemic bacterial loads and lung tissue damage, but the high homology of Hsp65 with the mammalian protein raises concern that pathological autoimmune responses may also be triggered. We searched for autoimmune responses elicited by DNA-hsp65 immunotherapy in mice chronically infected with TB by evaluating the humoral immune response and comprehensive histopathology using stereology. Cross-reactive antibodies between mycobacterial and mammalian Hsp60/65 were detected; however, no signs of pathological autoimmunity were found up to 60 days after the end of the therapy.

Em 1993, a Organização Mundial da Saúde declarou a tuberculose (TB) como uma emergência global devido à sua relevância epidemiológica e a necessidade de seu controle. Atualmente, a TB ainda é considerada um problema de saúde pública e requer o desenvolvimento de vacinas e terapias que sejam mais eficazes na sua prevenção e tratamento. Nesse sentido, o Laboratório de Vacinas Gênicas da Faculdade de Medicina de Ribeirão Preto estuda há mais de dez anos a eficácia da vacina gênica DNAhsp65 na profilaxia e terapia da TB. Com o intuito de complementar o conhecimento existente sobre os mecanismos imunes desencadeados pela vacina DNAhsp65, assim como sua associação às drogas convencionais utilizadas no tratamento da TB, objetivou-se neste trabalho a caracterização de células natural killer (NK), T natural killer (NKT), e T ?? na imunoterapia da tuberculose experimental com a vacina DNAhsp65, no tratamento com as drogas rifampicina (RIF) e isoniazida (INH), e na associação DNAhsp65-drogas. Inicialmente, camundongos BALB/c foram infectados com Mycobacterium tuberculosis (Mtb) cepa H37Rv no dia 0 e nos dias 1, 7, 15, 30 e 70 após a infecção, foi promovida a eutanásia dos animais infectados ou não (controle) para análise das células T não convencionais no pulmão por citometria de fluxo. No dia 30 após a infecção, os animais infectados receberam os diferentes tratamentos: vacina DNAhsp65, vetor pVAX1, drogas RIF e INH, ou as drogas em associação à vacina. Dez dias após o fim dos tratamentos, foi promovida a eutanásia dos animais para análise das populações celulares no pulmão e linfonodo por citometria de fluxo, imunohistoquímica e PCR em tempo real. Os animais somente infectados com Mtb apresentaram aumento significativo no número das células NK (CD3-CD49b+), NKT (CD3+CD49b+) e T ?? (CD3+??+) logo na primeira semana após a infecção, e esta diferença em relação aos animais controle permaneceu em até 70 dias após a infecção. Entre as células NK presentes no pulmão, observou-se predominância da subpopulação CD11bhighCD27low em todos os animais. Nos animais infectados, verificou-se aumento significativo das subpopulações de NK: CD11bhighCD27high e CD11blowCD27high, nos dias 7 e 15 e somente no dia 15 após a infecção, respectivamente. Entre a população de células T ?? presentes no pulmão, houve predomínio do fenótipo CD27- em animais controles e infectados nos diferentes tempos experimentais. Quanto aos animais infectados com Mtb e tratados com DNAhsp65, verificou-se aumento significativo de células T ?? produtoras de IFN-? e IL-17 no pulmão, e apesar de não ter sido observada diferença na freqüência de células NK e NKT neste grupo, as células NK apresentavam maior expressão da molécula FasL relacionada à morte celular induzida por apoptose. Nos grupos drogas e DNAhsp65-drogas observou-se aumento da freqüência de células T ?? no pulmão, assim como aumento de células NK produtoras de IL-10 e que expressavam o marcador de ativação CD69. Os resultados deste trabalho mostram mais uma vez a eficácia da vacina DNAhsp65 e da associação DNAhsp65- drogas no tratamento de animais infectados com Mtb e sugerem que células T não convencionais como as células NK, NKT e T ?? podem participar na modulação da resposta immune na TB. Estes achados devem ser levados em consideração no desenho de novas estratégias terapêuticas e também profiláticas para a TB. In 1993, the World Health Organization declared tuberculosis (TB) as a global emergence due to its epidemical relevance and the need to improve its control. Nowadays, TB still remains a public health problem and requires the development of more effective vaccines and therapies. In this sense, the Laboratory of Genetic Vaccines from the School of Medicine of Ribeirão Preto studies, for more than ten years, the efficiency of the genetic vaccine DNAhsp65 in TB prophylaxis and therapy. In order to complement the knowledge about the immune mechanisms triggered by DNAhsp65 vaccine and by its association with conventional drugs used in TB, our aim in this work was to characterize natural killer (NK), natural killer T (NKT) and gamma-delta (??) T cells in the immunotherapy of experimental tuberculosis with the DNAhsp65 vaccine, in the treatment with rifampicin and isoniazid drugs and in the association DNAhsp65-drugs. Initially, BALB/c mice were infected with Mtb strain H37Rv on day 0, and on days 1, 7, 15, 30 and 70 after infection, infected animals or not (control) were euthanized for lung cell analysis by flow cytometry. On day 30 after infection, infected animals received the following treatment: DNAhsp65 vaccine, pVAX1 vector, rifampicin and isoniazid drugs, or drugs in association with DNAhsp65. Ten days after the end of treatment, animals were euthanized for lung and lymph node cell analysis by flow cytometry, immunohistochemistry and real time PCR. Infected animals showed a significant increase of NK (CD3-CD49b+), NKT (CD3+CD49b+) and ?? (CD3+??+) T cells in the first week of infection and this difference compared to control animals remained until 70 days after infection. Within the lung NK cell population, we observed a predominance of CD11bhighCD27low phenotype in all animals. In infected animals, we verified a significant increase of the following NK cell subpopulations: CD11bhighCD27high and CD11blowCD27high on days 7 and 15, and only on day 15 after infection, respectively. Within the lung ?? T cell population, there was a predominance of CD27- ?? T cell in control and infected animals in the different experimental times. In infected animals and subsequently vaccinated with DNAhsp65, we verified a significant increase in ?? T cells producing IFN-? and IL-17 in the lungs. Although we have not seen any differences in NK and NKT cells in this group, NK cells showed higher expression of FasL molecule related to induced cell death by apoptosis. In DNAhsp65-drugs and drugs groups, we observed an increase in lung ?? T cells frequency, as well as increase in NK cells producing IL-10 and expressing CD69, an activation marker. Our results confirm the effectiveness of DNAhsp65 vaccine and its association with drugs in Mtb infected animals and suggest a modulation in the immune response through unconventional T cells such as NK, NKT and ?? T cells. These findings should be taken into consideration in the design of new therapeutic and prophylactic strategies for TB.