Hepatoprotective effect of tumour necrosis factor alpha blockade in psoriatic arthritis: a cross-sectional study

Objective To evaluate the impact of tumour necrosis factor α (TNFα) blockers on the presence of liver fibrosis in patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) treated with methotrexate (MTX). Methods Participants were consecutive patients with RA and PsA who had undergone MTX treatment for at least 1 year ± TNF blockade for over 6 months. Liver fibrosis was assessed using non-invasive transient elastography (FibroScan). Regression models were used to compare FibroScan values of patients with RA and patients with PsA receiving TNFα blockers with those who were not. Results FibroScan assessments were performed on 51 patients with RA and 43 patients with PsA. Compared to patients with RA, those with PsA were predominantly young men, received lower cumulative dosages of MTX and exhibited a higher incidence of liver steatosis and hyperlipidaemia. An abnormal result was observed in 7.1% of the anti-TNFα-naïve and in 13% of the anti-TNFα-treated patients in the RA group and in 30% of the anti-TNFα-naïve and 4.3% of the anti-TNFα-treated patients in the PsA group (OR=0.11, 95% CI 0.02 to 0.98). Results of the PsA group were robust when adjusted for baseline characteristics. Conclusion The results suggest a protective effect of TNFα inhibitors against the development of liver fibrosis in patients with PsA.

Evolution of radiographic joint damage in rituximab-treated versus TNF-treated rheumatoid arthritis cases with inadequate response to TNF antagonists

Observational studies have suggested that patients with rheumatoid arthritis (RA) who experience inadequate response to anti-tumour necrosis factor (anti-TNF) agents respond more favourably to rituximab (RTX) than to an alternative anti-TNF agent. However, the relative effectiveness of these agents on long-term outcomes, particularly in radiographic damage, remains unclear.

The -308 tumour necrosis factor-alpha gene polymorphism predicts therapeutic response to TNFalpha-blockers in rheumatoid arthritis and spondyloarthritis patients

OBJECTIVE: To examine whether the G-to-A polymorphism at position -308 in the promoter of the tumour necrosis factor-alpha (TNFalpha) gene influences the therapeutic response to TNFalpha-blockers in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS). METHODS: A total of 54 patients with RA, 10 with PsA and 22 with AS were genotyped by polymerase chain reaction for the -308 TNFalpha promoter polymorphism. They were treated with infliximab (n = 63), adalimumab (n = 10) or etanercept (n = 13). Clinical response was assessed after 24 weeks by the Disease Activity Score in 28 joints (DAS28) for RA and PsA, and the Bath Ankylosing Spondylitis Activity Index (BASDAI) for AS patients. RESULTS: All patients with the A/A genotype (n = 3, all RA) and two patients with the A/G genotype (AS) failed to respond to anti-TNF treatment. Irrespective of the underlying disease, moderate response (n = 44) was predominantly associated with the A/G genotype (A/G 18/22, G/G 4/22), whereas good response (n = 59) was exclusively seen in patients with the G/G genotype. The average improvement in the DAS28 score was 0.83 in the A/A, 1.50 in the A/G and 2.64 in the G/G group of RA and PsA patients (P < 0.0001). The BASDAI score in AS improved on average by 1.21 in the A/G and by 3.30 in the G/G group (P < 0.005). CONCLUSIONS: The data suggest that humans with a TNFalpha -308 G/G genotype are better responders to anti-TNFalpha treatment than those with A/A or A/G genotypes independent of the treated rheumatic disease (RA, PsA or AS).

Intravenous immunoglobulin preparations contain anti-Siglec-8 autoantibodies

BACKGROUND: Human intravenous immunoglobulin (IVIg) preparations are used for the treatment of autoimmune and allergic diseases. Natural autoantibodies are believed to contribute to IVIg-mediated anti-inflammatory effects. OBJECTIVE: To address the question of whether IVIg preparations contain anti-sialic acid-binding Ig-like lectin-8 (anti-Siglec-8) autoantibodies. METHODS: The presence of possible anti-Siglec-8 autoantibodies in IVIg preparations was first examined by functional eosinophil death and apoptosis assays. Specificity of IVIg effects was shown by depleting anti-Siglec-8 autoantibodies from IVIg. Binding of purified anti-Siglec-8 autoantibodies to recombinant Siglec-8 was demonstrated by an immunodot assay. RESULTS: IVIg exerts cytotoxic effects on purified human blood eosinophils. Both potency and efficacy of the IVIg-mediated eosinophil killing effect was enhanced by IL-5, granulocyte/macrophage colony-stimulating factor, IFN-gamma, TNF-alpha, and leptin. Similarly, inflammatory eosinophils obtained from patients suffering from the hypereosinophilic syndrome (HES) demonstrated increased Siglec-8 cytotoxic responses when compared with normal blood eosinophils. Pharmacologic blocking experiments indicated that the IVIg-mediated additional eosinophil death in the presence of cytokines is largely caspase-independent, but it depends on reactive oxygen species. Anti-Siglec-8 autoantibody-depleted IVIg failed to induce caspase-independent eosinophil death. CONCLUSION: IVIg preparations contain natural anti-Siglec-8 autoantibodies. CLINICAL IMPLICATIONS: Anti-Siglec-8 autoantibodies present in IVIg preparations may have therapeutic relevance in autoimmune and allergic diseases, respectively, such as Churg-Strauss syndrome.

Association between burnout and circulating levels of pro- and anti-inflammatory cytokines in schoolteachers

OBJECTIVE: The burnout syndrome has been associated with an increased risk of cardiovascular disease. The physiological mechanisms potentially involved in this link are underexplored. Knowing that a chronic low-grade systemic inflammatory state contributes to atherosclerosis, we investigated circulating cytokine levels in relation to burnout symptoms. METHODS: We studied 167 schoolteachers (median, 48 years; range, 23-63 years; 67% women) who completed the Maslach Burnout Inventory with its three subscales emotional exhaustion (EE), lack of accomplishment (LA), and depersonalization (DP). Levels of the proinflammatory cytokine tumor necrosis factor (TNF)-alpha and of the anti-inflammatory cytokines interleukin (IL)-4 and IL-10 were determined in fasting morning plasma samples. The TNF-alpha/IL-4 ratio and the TNF-alpha/IL-10 ratio were computed as two indices of increased inflammatory activity. Analyses were adjusted for demographic factors, medication, lifestyle factors (including sleep quality), metabolic factors, and symptoms of depression and anxiety. RESULTS: Higher levels of total burnout symptoms aggregating the EE, LA, and DP subscales independently predicted higher TNF-alpha levels (DeltaR(2)=.024, P=.046), lower IL-4 levels (DeltaR(2)=.021, P=.061), and a higher TNF-alpha/IL-4 ratio (DeltaR(2)=.040, P=.008). Higher levels of LA predicted decreased IL-4 levels (DeltaR(2)=.041, P=.008) and a higher TNF-alpha/IL-4 ratio (DeltaR(2)=.041, P=.007). The categorical dimensions of the various burnout scales (e.g., burnout yes vs. no) showed no independent relationship with any cytokine measure. CONCLUSION: Burnout was associated with increased systemic inflammation along a continuum of symptom severity rather than categorically. Given that low-grade systemic inflammation promotes atherosclerosis, our findings may provide one explanation for the increased cardiovascular risk previously observed in burned-out individuals.

Hypoxia inducible factor-1 alpha induction by tumour necrosis factor-alpha, but not by toll-like receptor agonists, modulates cellular respiration in cultured human hepatocytes

BACKGROUND/AIMS: Genes encoding for some of the mitochondrial proteins are under the control of the transcriptional factor hypoxia inducible factor-1 alpha (HIF-1 alpha), which can accumulate under normoxic conditions in inflammatory states. The aim of this study was to evaluate the effects of cobalt chloride (CoCl(2), a hypoxia mimicking agent), tumour necrosis factor-alpha (TNF-alpha) and toll-like receptor (TLR) -2, -3 and -4 agonists on HIF-1 alpha accumulation, and further on HIF-1 alpha-mediated modulation of mitochondrial respiration in cultured human hepatocytes. METHODS: The human hepatoma cell line HepG2 was used in this study. Cells were treated with CoCl(2), TNF-alpha and TLR-2, -3 and -4 agonists. HIF-1 alpha was determined by Western blotting and mitochondrial respiration in stimulated cells by high-resolution respirometry. RESULTS: CoCl(2), TNF-alpha and TLR agonists induced the expression of HIF-1 alpha in a time-dependent fashion. TNF-alpha and CoCl(2), but not TLR agonists, induced a reduction in complex I-, II- and IV-dependent mitochondrial oxygen consumption. TNF-alpha-associated reduction of cellular oxygen consumption was abolished through inhibition of HIF-1 alpha activity by chetomin (CTM). Pretreatment with cyclosporine A prevented CoCl(2)-induced reduction of complex I- and II-dependent mitochondrial oxygen consumption and TNF-alpha-induced reduction of complex-I-dependent respiration, implicating the involvement of the mitochondrial permeability transition pore openings. TNF-alpha and TLR-2, -3 and -4 agonists induced the expression of vascular endothelial growth factor, which was partially abolished by the blockage of HIF-1 alpha with CTM. CONCLUSIONS: The data suggest that HIF-1 alpha modulates mitochondrial respiration during CoCl(2) and TNF-alpha stimulation, whereas it has no effect when induced with TLR-2, -3 and -4 agonists.

Dissection of antitumor activity by lymphokine -activated killer cells: Role of FcR+ precursors and obligatory role of tumor necrosis factor-$\alpha$ in antibody -dependent cellular cytotoxicity

Human peripheral blood lymphocytes (PBL) cultured for varying lengths of time in IL-2 are able to mediate antibody independent cellular cytotoxicity (AICC) as well as antibody dependent cellular cytotoxicity (ADCC) against a wide range of tumor targets. The objective of our study is to determine the cytotoxic potential of the subset of LAK cells involved in ADCC, the tumor recognition mechanism in ADCC, the kinetics of ADCC mediated by PBL cultured under various conditions and the role of TNF-$\alpha$ in the development and maturation of ADCC effectors in the LAK population.^ The model system in this study for ADCC used a monoclonal antibody 14G2a (IgG2a), that recognizes the GD2 epitope on human melanoma cell line, SK-Mel-1. The target recognition mechanism operative in AICC (traditionally known as lymphokine activated killing or LAK) is an acquired property of these IL-2 activated cells which confers on them the unique ability to distinguish between tumor and normal cells. This recognition probably involves the presence of a trypsin sensitive N-linked glycoprotein epitope on tumor cells. Proteolytic treatment of the tumor cells with trypsin renders them resistant to AICC by PBL cultured in IL-2. However, ADCC is unaffected. This ADCC, mediated by the relatively small population of cells that are positive for the Fc receptor for IgG (FcR), is an indication that this subset of "LAK" cells does not require the trypsin sensitive epitope on tumor cells to mediate killing. Enriching PBL for FcR+ cells markedly enhanced both AICC and ADCC and also reduced the IL-2 requirement of these cells.^ The stoichiometry of Fc receptor (FcR) expression on the cytotoxic effectors does not correlate with ADCC lytic activity. Although FcRs are necessary to mediate ADCC, other factors, appear to regulate the magnitude of cytolytic activity. In order to investigate these putative factors, the kinetics of ADCC development was studied under various conditions (in IL-2 (10u/ml) and 100u/ml), in IL-2(10u/ml) + TNF$\alpha$ (500u/ml) and in TNF-$\alpha$ (500u/ml) alone). Addition of exogenous TNF-$\alpha$ into the four hour cytotoxicity assay did not increase ADCC, nor did anti-TNF antibodies result in inhibition. On the other hand, addition of anti-TNF antibodies to PBL and IL-2 for 24 hours, resulted in a marked inhibition of the ADCC, suggesting that endogenous TNF-$\alpha$ is obligatory for the maturation and differentiation of ADCC effectors. ^

Identification of the galactose-adherence lectin epitopes of Entamoeba histolytica that stimulate tumor necrosis factor-alpha production by macrophages.

The 170-kDa subunit of the galactose-adherence lectin (Gal-lectin) of Entamoeba histolytica mediates adherence to human colonic mucins and intestinal epithelium as a prerequisite to amebic invasion. The Gal-lectin is an immunodominant molecule and a protective antigen in the gerbil model of amebiasis. Tumor necrosis factor alpha (TNF-alpha) produced by activated macrophages enhances nitric oxide-dependent cytotoxicity in host defense against E. histolytica. The purpose of this study was to identify the Gal-lectin epitopes which stimulate TNF-alpha production by macrophages. Murine bone marrow-derived macrophages (BMMs) exposed to Gal-lectin (100-500 ng/ml) stimulated stable expression of TNF-alpha mRNA (8-fold increase) and TNF-alpha production similar to that of lipopolysaccharide-stimulated cells (100 ng/ml). Polyclonal anti-lectin serum specifically inhibited TNF-alpha mRNA induction in response to the Gal-lectin but not to lipopolysaccharide. Anti-lectin monoclonal antibodies 8C12, H85 and 1G7, which recognize nonoverlapping epitopes of the cysteine-rich region of the 170-kDa heavy subunit, inhibited both amebic adherence to mammalian cells and Gal-lectin-stimulated TNF-alpha mRNA expression by BMMs,but monoclonal antibody 7F4 did neither. As these inhibitory antibodies map to amino acids 596-1082 of the 170-kDa Gal-lectin, our results have identified the functional region that mediates amebic adherence and TNF-alpha mRNA induction in BMMMs; thus, this region of the Gal-lectin is a subunit vaccine candidate.

Spontaneous inflammatory demyelinating disease in transgenic mice showing central nervous system-specific expression of tumor necrosis factor alpha.

Cytokines are now recognized to play important roles in the physiology of the central nervous system (CNS) during health and disease. Tumor necrosis factor alpha (TNF-alpha) has been implicated in the pathogenesis of several human CNS disorders including multiple sclerosis, AIDS dementia, and cerebral malaria. We have generated transgenic mice that constitutively express a murine TNF-alpha transgene, under the control of its own promoter, specifically in their CNS and that spontaneously develop a chronic inflammatory demyelinating disease with 100% penetrance from around 3-8 weeks of age. High-level expression of the transgene was seen in neurons distributed throughout the brain. Disease is manifested by ataxia, seizures, and paresis and leads to early death. Histopathological analysis revealed infiltration of the meninges and CNS parenchyma by CD4+ and CD8+ T lymphocytes, widespread reactive astrocytosis and microgliosis, and focal demyelination. The direct action of TNF-alpha in the pathogenesis of this disease was confirmed by peripheral administration of a neutralizing anti-murine TNF-alpha antibody. This treatment completely prevented the development of neurological symptoms, T-cell infiltration into the CNS parenchyma, astrocytosis, and demyelination, and greatly reduced the severity of reactive microgliosis. These results demonstrate that overexpression of TNF-alpha in the CNS can cause abnormalities in nervous system structure and function. The disease induced in TNF-alpha transgenic mice shows clinical and histopathological features characteristic of inflammatory demyelinating CNS disorders in humans, and these mice represent a relevant in vivo model for their further study.

Extração, determinação da composição fenólica e avaliação do potencial de desativação de espécies reativas de oxigênio e da atividade anti-inflamatória de resíduos de amendoim, pimenta-rosa e pimenta-do-reino

O setor agroindustrial tem se expandido muito nos últimos anos, levando o país a um aumento na geração de resíduos agroindustriais, sendo que a maior parte deles ainda é descartada no meio ambiente, sem tratamento adequado, ou utilizada na alimentação animal, destinos que a priori, não geram ganhos econômicos para a agroindústria além de representarem gargalos logísticos e ambientais na sua disposição. Nesse sentido, o presente trabalho teve como objetivos otimizar o processo de extração de compostos bioativos, avaliar in vitro as atividades antioxidante, por meio da desativação de espécies reativas de oxigênio, e anti-inflamatória, bem como determinar a composição fenólica dos resíduos agroindustriais a saber: película de amendoim (Arachis hypogaea) (cultivares IAC886 e IAC505), pimenta-rosa (Schinus terebinthifolius Raddi) e pimenta-do-reino (Piper Nigrum L). O processo de otimização da extração de compostos antioxidantes foi realizado utilizando dois processos de extração, extração convencional e subcrítica, em delineamento composto central rotacional, utilizando como variáveis a temperatura e tempo e a pressão e temperatura, respectivamente, com os solventes etanol 80%, água e propilenoglicol 80%. Durante o processo de otimização a atividade antioxidante foi avaliada pelo método de sequestro do radical ABTS. Os melhores resultados foram obtidos para a extração convencional com os solventes etanol 80%, água e propilenoglicol 80%. A película de amendoim (IAC505) apresentou as maiores atividades antioxidantes (1.396,67, 580,44 e 859,89 μmol.g-1 em equivalentes de trolox, para os solventes etanol 80%, água e propilenoglicol 80%, respectivamente). A partir dos resultados obtidos para os solventes testados, utilizando a extração convencional, foram feitas outras análises de atividade antioxidante considerando o tempo e temperatura ideal de extração. Foram realizadas análises de avaliação da capacidade de redução de Folin-Ciocalteau e potencial de desativação dos radicais livres sintéticos (DPPH e ABTS) e espécies reativas de oxigênio (radicais peroxila, superóxido e ácido hipocloroso). O solvente de extração que apresentou melhores resultados em todos os ensaios foi o etanol 80%, sendo, portanto o solvente utilizado nas análises subsequentes. A partir da definição do melhor sistema extrator foram realizadas análises da composição fenólica, por meio das técnicas de cromatografia líquida de alta eficiência em modo analítico (HPLC-RP), cromatografia gasosa acoplada com espectrometria de massas (GC-MS), e avaliação in vitro da atividade anti-inflamatória. Foram identificados nos resíduos estudados procianidinas B1 e B2, ácido p-cumárico, miricetina, ácido ferúlico, ácido siríngico, ácido sinápico, epicatequina e catequina. A pimenta-do-reino diminui significativamente os níveis de TNF-α e nitritos, reduzindo assim o processo inflamatório gerado. Os resultados obtidos neste trabalho demonstram que estes resíduos agroindústrias possuem grande potencial biológico, podendo assim ser melhores aproveitados tanto pela indústria de alimentos quanto pela indústria farmacêutica.

Anti-tumor necrosis factor therapy: The Australian experience

Anti-tumor necrosis factor (TNF) therapy for the management of rheumatic diseases has been reimbursed in Australia progressively per agent and disease indication since 2003. Initial projections of uptake were grossly overestimated. In this article the anti-TNF experience in Australia is reviewed, including results of an eligibility study, Australian Rheumatology Association guidelines, anti-TNF registry, and a report of adverse effects. These observations may assist APLAR countries currently coming to terms with anti-TNF drug registration and funding.

Effects of 15d-PGJ(2)-loaded poly(D,L-lactide-co-glycolide) nanocapsules on inflammation

BACKGROUND and PURPOSEThe PPAR-gamma agonist 15d-PGJ(2) is a potent anti-inflammatory agent but only at high doses. To improve the efficiency of 15d-PGJ(2), we used poly(D,L-lactide-co-glycolide) nanocapsules to encapsulate it, and function as a drug carrier system. The effects of these loaded nanocapsules (15d-PGJ(2)-NC) on inflammation induced by different stimuli were compared with those of free 15d-PGJ(2).EXPERIMENTAL APPROACHMice were pretreated (s.c.) with either 15d-PGJ(2)-NC or unloaded 15d-PGJ(2) (3, 10 or 30 mu g center dot kg-1), before induction of an inflammatory response by i.p. injection of either endotoxin (LPS), carrageenan (Cg) or mBSA (immune response).KEY RESULTSThe 15d-PGJ(2)-NC complex did not display changes in physico-chemical parameters or drug association efficiency over time, and was stable for up to 60 days of storage. Neutrophil migration induced by i.p. administration of LPS, Cg or mBSA was inhibited by 15d-PGJ(2)-NC, but not by unloaded 15d-PGJ(2). In the Cg model, 15d-PGJ(2)-NC markedly inhibited serum levels of the pro-inflammatory cytokines TNF-alpha, IL-1 beta and IL-12p70. Importantly, 15d-PGJ(2)-NC released high amounts of 15d-PGJ(2), reaching a peak between 2 and 8 h after administration. 15d-PGJ(2) was detected in mouse serum after 24 h, indicating sustained release from the carrier. When the same concentration of unloaded 15d-PGJ(2) was administered, only small amounts of 15d-PGJ(2) were found in the serum after a few hours.CONCLUSIONS and IMPLICATIONSThe present findings clearly indicate the potential of the novel anti-inflammatory 15d-PGJ(2) carrier formulation, administered systemically. The formulation enables the use of a much smaller drug dose, and is significantly more effective compared with unloaded 15d-PGJ(2).

Infliximab Induces Increase in Triglyceride Levels in Psoriatic Arthritis Patients

Objectives. To evaluate lipid profile changes after anti-TNF therapy in patients with psoriatic arthritis (PsA). Methods. Fifteen PsA patients (eight polyarticular, four oligoarticular, two axial, and one mutilating) under infliximab were included. None had dyslipoproteinemia or previous statin use. Total cholesterol (TC) and its fractions, inflammatory markers, and prednisone use were evaluated. Results. The comparisons of lipid levels between baseline and after three months (3M) of anti-TNF therapy showed that there was a significant increase in mean triglycerides (117.8 +/- 49.7 versus 140.1 +/- 64.1 mg/dL, P = 0.028) and VLDL-c (23.6 +/- 10.5 versus 28.4 +/- 13.7 mg/dL, P = 0.019) levels. In contrast, there were no differences in the mean TC (P = 0.28), LDL-c (P = 0.42), and HDL-c (P = 0.26) levels. Analysis of the frequencies of each lipid alteration at baseline and at 3M were alike (P > 0.05). Positive correlations were found between VLDL-c and CRP (r = 0.647, P = 0.009) and between triglycerides and CRP (r = 0.604, P = 0.017) levels at 3M. ESR reduction was observed after 3M (P = 0.04). Mean prednisone dose remained stable at beginning and at 3M (P = 0.37). Conclusion. This study demonstrated that anti-TNF may increase TG and VLDL-c levels in PsA patients after three months.

IL-17 Produced during Trypanosoma cruzi Infection Plays a Central Role in Regulating Parasite-Induced Myocarditis

Background: Chagas disease is a neglected disease caused by the intracellular parasite Trypanosoma cruzi. Around 30% of the infected patients develop chronic cardiomyopathy or megasyndromes, which are high-cost morbid conditions. Immune response against myocardial self-antigens and exacerbated Th1 cytokine production has been associated with the pathogenesis of the disease. As IL-17 is involved in the pathogenesis of several autoimmune, inflammatory and infectious diseases, we investigated its role during the infection with T. cruzi. Methodology/Principal Findings: First, we detected significant amounts of CD4, CD8 and NK cells producing IL-17 after incubating live parasites with spleen cells from normal BALB/c mice. IL-17 is also produced in vivo by CD4(+), CD8(+) and NK cells from BALB/c mice on the early acute phase of infection. Treatment of infected mice with anti-mouse IL-17 mAb resulted in increased myocarditis, premature mortality, and decreased parasite load in the heart. IL-17 neutralization resulted in increased production of IL-12, IFN-gamma and TNF-alpha and enhanced specific type 1 chemokine and chemokine receptors expression. Moreover, the results showed that IL-17 regulates T-bet, ROR gamma t and STAT-3 expression in the heart, showing that IL-17 controls the differentiation of Th1 cells in infected mice. Conclusion/Significance: These results show that IL-17 controls the resistance to T. cruzi infection in mice regulating the Th1 cells differentiation, cytokine and chemokine production and control parasite-induced myocarditis, regulating the influx of inflammatory cells to the heart tissue. Correlations between the levels of IL-17, the extent of myocardial destruction, and the evolution of cardiac disease could identify a clinical marker of disease progression and may help in the design of alternative therapies for the control of chronic morbidity of chagasic patients.

Intranasal vaccination with messenger RNA as a new approach in gene therapy: Use against tuberculosis

Background: mRNAs are highly versatile, non-toxic molecules that are easy to produce and store, which can allow transient protein expression in all cell types. The safety aspects of mRNA-based treatments in gene therapy make this molecule one of the most promising active components of therapeutic or prophylactic methods. The use of mRNA as strategy for the stimulation of the immune system has been used mainly in current strategies for the cancer treatment but until now no one tested this molecule as vaccine for infectious disease. Results: We produce messenger RNA of Hsp65 protein from Mycobacterium leprae and show that vaccination of mice with a single dose of 10 mu g of naked mRNA-Hsp65 through intranasal route was able to induce protection against subsequent challenge with virulent strain of Mycobacterium tuberculosis. Moreover it was shown that this immunization was associated with specific production of IL-10 and TNF-alpha in spleen. In order to determine if antigen presenting cells (APCs) present in the lung are capable of capture the mRNA, labeled mRNA-Hsp65 was administered by intranasal route and lung APCs were analyzed by flow cytometry. These experiments showed that after 30 minutes until 8 hours the populations of CD11c(+), CD11b(+) and CD19(+) cells were able to capture the mRNA. We also demonstrated in vitro that mRNA-Hsp65 leads nitric oxide (NO) production through Toll-like receptor 7 (TLR7). Conclusions: Taken together, our results showed a novel and efficient strategy to control experimental tuberculosis, besides opening novel perspectives for the use of mRNA in vaccines against infectious diseases and clarifying the mechanisms involved in the disease protection we noticed as well.