Genetic variability of hepatitis B virus in acute and in different phases of chronic infection in Brazil.

The selection pressure imposed by the host immune system impacts on hepatitis B virus (HBV) variability. This study evaluates HBV genetic diversity, nucleos(t)ide analogs resistance and HBsAg escape mutations in HBV patients under distinct selective pressures. One hundred and thirteen individuals in different phases of HBV infection were included: 13 HBeAg-positive chronic infection, 9 HBeAg-positive chronic hepatitis, 47 HBeAg-negative chronic infection (ENI), 29 HBeAg-negative chronic hepatitis (ENH) and 15 acute infected individuals. Samples were PCR amplified, sequenced and genetically analyzed for the overlapping POL/S genes. Most HBV carriers presented genotype A (84/113; 74.3%), subgenotype A1 (67/84; 79.7%), irrespective of group, followed by genotypes D (20/113; 17.7%), F (8/113; 7.1%) and E (1/113; 0.9%). Clinically relevant mutations in polymerase (tL180M/M204V) and in the Major Hydrophilic Region of HBsAg (sY100C, T118A/M, sM133T, sD144A and sG145R) were observed. Our findings, however, indicated that most polymorphic sites were located in the cytosolic loops (CYL1-2) and transmembrane domain 4 (TMD4) of HBsAg. Lower viral loads and higher HBV genetic diversity were observed in ENI and ENH groups (p < 0.001), suggesting that these groups are subjected to a higher selective pressure. Our results provide information on the molecular characteristics of HBV in a diverse clinical setting, and may guide future studies on the balance of HBV quasispecies at different stages of infection.

Applicability of oral fluid samples for tracking hepatitis B virus mutations, genotyping, and phylogenetic analysis.

Little is known about the usefulness of saliva samples for hepatitis B virus (HBV) genotyping and mutation analysis. The aim of this study was to evaluate the usefulness of oral fluid samples to determine HBV genotype distribution, S/polymerase mutations, and HBV subpopulation diversity among chronically HBV-infected individuals. Serum and oral fluid samples were obtained from 18 individuals for PCR and nucleotide sequencing of the HBV surface antigen gene. Biochemical analysis of liver enzymes (ALT, AST, GGT) and HBV, HCV, and HIV serological tests were also performed. All serum samples were HBsAg (+), anti-HBc (+), and anti-HBs (-); 55.6% were HBeAg (+)/anti-HBe (-), and 11.1% were anti-HIV (+). The mean HBV DNA viral load was 6.1 ± 2.3 log IU/mL. The HBV genotype distribution was as follows: A, 72.2%; D, 11.1%; E, 5.6%; F, 11.1%. A concordance of 100% in genotype classification and 99.8% in sequence similarity between paired oral fluid and serum samples was observed. HBsAg mutations were detected in all samples, but no resistance mutations were found in the polymerase gene. This study demonstrates that oral fluid samples can be used reliably for tracking HBV mutations, genotyping, and phylogenetic analysis. This could be important for molecular epidemiology studies with hard-to-reach populations.

High prevalence of hepatitis A in indigenous population in north Brazil.

OBJECTIVES: Little is known about hepatitis A virus (HAV) prevalence in indigenous communities. This study aims to evaluate the prevalence of HAV in indigenous community compared to urban population located at Western Amazon in Brazil. RESULTS: A total of 872 serum samples were obtained from 491 indigenous and 381 non indigenous individuals aging 0 to 90 years. Samples were tested for total and IgM anti-HAV and positive IgM samples were tested for HAV RNA. The overall prevalence of total anti-HAV was 87%, increased according age showing 100% of prevalence in those aging more than 30 years (p < 0.0001) and it was similar among indigenous and urban population. Total anti-HAV prevalence varied between tribes (p < 0.0001) and urban sites (p = 0.0014) and spatial distribution showed high prevalence in homes that received up to 100 dollars. IgM anti-HAV prevalence was 1.7% with predominance in males, those aging more than 41 years. No HAV RNA was detected. In conclusion, high overall anti-HAV prevalence was found in indigenous communities in North Brazil demonstrating the importance of universal vaccination in this group.

Epidemiology of hepatitis B and C virus infection in Central West Argentina.

Little information is available regarding the prevalence of viral hepatitis in Central West Argentina. This study aims to give new information regarding HBV and HCV prevalence, genotypes, and risk factors in Central West Argentina and the suitability of dried blood spot (DBS) sampling for HBV and HCV screening. METHODS: A total of 622 individuals were included; the mean age was 36.6 ± 14.3 years and 55.4% were females. HBV and HCV markers were detected using serological and molecular analysis, and risk factors were evaluated using statistical analysis. RESULTS: Using serum samples, the HBsAg prevalence was 1.8%, the rate of HBV exposure (anti-HBc positivity) was 5.3%, and the rate of HBV immunity was 34.9%. HBV DNA was found in four out of 11 HBsAg+ samples, and the viruses in three of these samples were classified as genotypes A1, A2 and F2a. Multivariate analysis showed that anti-HBs positivity was associated with the level of schooling and history of HBV vaccination. The anti-HCV prevalence was 2.6%, and HCV RNA was found in 11 samples, seven of which contained viruses of genotypes 1a (n = 2), 1b (n = 3) and 2 (n = 2). The sensitivity of the DBS assay for HBsAg, anti-HBc, and anti-HCV was 100%, 66.6%, and 75%, respectively, and the specificity was above 98% for all markers when compared to serum. CONCLUSION: A low rate of HBV immunity was observed, demonstrating the importance of HBV vaccination. High HCV prevalence was found, and HCV 1b was closely related to other Argentinian isolates. Finally, the performance of DBS testing in this population needs more optimization to increase its sensitivity and specificity.

Prevalence of hepatitis B and hepatitis C among diabetes mellitus type 2 individuals.

Diabetes mellitus type 2 (DM2) patients have higher risk to be infected with parenterally transmitted viruses, like hepatitis B or C virus. This study aims to determine HBV and HCV infection prevalence in DM2 patients from Northeast and Southeast Brazil. A total of 537 DM2 patients were included, 194 (36.12%) males and 343 (63.87%) females, with mean age of 57.13±11.49 years. HBV and HCV markers were determined using serological and molecular analysis, and risk factors were evaluated in a subgroup from Southeast (n = 84). Two HBV acute (HBsAg+/anti-HBc -) and one HBV chronic case (HBsAg+/anti-HBc+) were found. Six individuals (1.1%) were isolated anti-HBc, 37 (6.9%) had HBV infection resolved (anti-HBc+/anti-HBs+), 40 (7.4%) were considered HBV vaccinated (anti-HBc-/anti-HBs+). Thirteen patients (2.42%) had anti-HCV and 7 of them were HCV RNA+. In the subgroup, anti-HBc positivity was associated to age and anti-HCV positivity was associated to age, time of diabetes diagnosis, total bilirubin, indirect bilirubin, alkaline phosphatase at bivariate analysis, but none of them was statistically significant at multivariate analysis. As conclusion, low prevalence of HBV and high prevalence HCV was found in DM2 patients.

Performance of point of care assays for hepatitis B and C viruses in chronic kidney disease patients.

AIMS: Point of care testing (POCT) has been used for hepatitis B and C diagnosis in general population, but little is known about the influence of clinical conditions in the accuracy of these assays. This study aims to evaluate the performance of POCTs for detection of hepatitis B virus surface antigen (HBsAg) and antibodies to Hepatitis C Virus (anti-HCV) in Chronic Kidney Disease (CKD) patients. METHODS: A total of 286 subjects were included in this study. HBsAg and anti-HCV were detected using commercial EIAs and four POCTs: HBsAg (WAMA Imuno-Rápido HBsAg and VIKIA HBsAg) and anti-HCV (DOLES HCV teste rápido and WAMA Imuno-Rápido anti-HCV) in serum and whole blood. RESULTS: Using EIA, HBsAg and anti-HCV prevalence was 4.5% and 16.1% in CKD patients. HBsAg and anti-HCV POCTs had sensitivities from 92.3% to 100% and 84.8% to 89.1% while specificities were 99.3% to 100% and 99.2% to 99.6%, respectively. POCT using serum samples performed well compared with whole blood samples and true positive samples of POCTs had high optical density to cut-off (OD/CO) values compared with EIA. CONCLUSIONS: This study demonstrates good performance of HBsAg and anti-HCV POCTs in CKD patients, especially in serum samples indicating low interference of this disease in the performance of these assays. POCTs could be an important tool for HBV and HCV screening in high-risk populations.

Comparison of the performance of enzyme immunoassays for hepatitis B and C detection in dried blood spot.

Dried blood spots (DBSs) could be an alternative to serum for hepatitis B virus (HBV) and hepatitis C virus (HCV) diagnosis. This study aims to evaluate two enzyme immunoassays (EIAs) for HBsAg and anti-HCV detection using DBS. Serum was tested using commercial EIA. DBS was tested using optimized EIA developed for serum and commercial EIA developed for DBS (Imunoscreen). Concordances between DBS and serum samples for both markers and EIAs were higher than 97%. Both EIAs demonstrated good performance for HBsAg and anti-HCV detection using DBS, and these methods could be used unchangeably increasing the access for HBV and HCV diagnosis.

High prevalence of insulin resistance among Brazilian chronic hepatitis C patients

ABSTRACT Objective: This study aims to estimate the prevalence of insulin resistance (IR) among chronic hepatitis C (CHC) patients and their related laboratory and demographic data. Subjects and methods: In this study, non-diabetic CHC patients referred to Viral Hepatitis Ambulatories from Rio de Janeiro (Brazil) donated blood samples. Insulin was measured using a chemiluminescence immunoassay. IR was determined by HOMA-IR, where HOMA-IR > 2 was defined as IR. Results: A total of 214 CHC patients were recruited (123 females aged 53.6 years ± 10.9 years). IR was present in 133 patients (62.1%) and was associated in bivariate analysis to higher mean values of age (p = 0.040), triglycerides (p = 0.032), glucose (p = 0.000), insulin (p = 0.000), waist circumference (p = 0.001), and body mass index (p = 0.007); however, none of these variables were significant in the multivariate analysis. Conclusions: The high prevalence of IR was observed among CHC patients, and there was no difference in clinical or laboratory parameters when both groups were compared in the multivariate analysis. This high IR prevalence could lead to a high risk for development of cardiovascular disease and metabolic disorders.

Performance of rapid diagnostic tests for detection of Hepatitis B and C markers in HIV infected patients.

There is little information describing the influence of HIV infection upon the performance of rapid diagnostic tests (RDTs) for hepatitis B and C virus diagnosis. This study aims to evaluate the performance of RDTs for HBsAg and anti-HCV detection among HIV-infected individuals. A total of 362 HIV infected individuals were recruited from clinics between January 2013 to November 2014 in the southeast and northeast of Brazil. HBsAg and anti-HCV were detected using commercial EIAs and four RDTs: HBV (Vikia HBsAg® and Wama Imuno-Rapido HBV®) and HCV (Bioeasy Teste Rápido HCV® and Wama Imuno-Rapido HCV®). Reactive HBsAg and anti-HCV serum samples were tested for HBV DNA and HCV RNA. Sensitivity, specificity and kappa statistic were determined. Using EIA, HBsAg and anti-HCV were detected in 14 (3.9%) and 37 (10.2%) serum samples respectively. Using serum only, HBsAg RDTs demonstrated sensitivities and specificities above 92.0% and Kappa values above 89.0%. Anti-HCV RDTs demonstrated sensitivity and specificities above 82.0% and Kappa higher than 89.0%. Using whole blood samples, Vikia HBsAg® and Wama Imuno-Rapido HCV® showed sensitivity and specificity above 99.0% with Kappa of 66.4% and 100%, respectively. HIV viral load was higher among discordant results for anti-HCV RDT. RDTs demonstrated good performance in HIV infected individuals showing the usefulness of assays in this population.

Lack of Association between Hepatitis C Virus core Gene Variation 70/91aa and Insulin Resistance.

The role of hepatitis C virus (HCV) in insulin resistance (IR) is not fully understood. The aim of this study was to determine the impact of amino acid (aa) substitutions in the core region of HCV according to IR and to identify clinical and laboratory associations. Ninety-two treatment-naive HCV patients were recruited to determine laboratory data and blood cell count. IR was determined using Homeostasis Model Assessment (HOMA) index where IR was defined as HOMA ≥2. HCV RNA load and genotype were determined by Abbott Real time HCV. HCV core region was determined by direct nucleotide sequencing. Bivariate analysis was conducted using HOMA IR ≥2 as a dependent factor. IR prevalence was 43.5% (n = 40), vitamin D sufficiency was found in 76.1% (n = 70) and 72.8% (n = 67) had advanced liver fibrosis. In the bivariate analyses, elevated values of γGT (p = 0.024) and fibrosis staging (p = 0.004) were associated with IR, but IR was not related to core mutations. The presence of glutamine in position 70 was associated with low vitamin D concentration (p = 0.005). In the multivariate analysis, no variable was independently associated with HOMA-IR. In conclusion, lack of association between IR and HCV core mutations in positions 70 and 91 suggests that genetic variability of this region has little impact on IR.

Performance of ANTI-HCV testing in dried blood spots and saliva according to HIV status.

The use of saliva and dried blood spots (DBS) could increase access to HCV diagnosis for high-risk populations, such as HIV-infected individuals, but the performance of these assays has not been well established in this group. This study aims to evaluate HIV status, particularly TCD4+ cell count and viral load, in the performance of anti-HCV testing using DBS and saliva. A total of 961 individuals classified as HCV+, HIV+, or HIV/HCV+, as well as negative controls, donated serum, DBS, and saliva samples for anti-HCV testing using a commercial enzyme immunoassay. Sample volume was modified for DBS and saliva, and an ROC curve was used for cut-off determination in saliva. Anti-HCV sensitivities were greater than 93% using DBS and saliva in the HCV+ group, while they were 83.3% and 95.6% for HCV/HIV+ individuals for DBS and saliva assays, respectively. Specificity varied from 91.7% to 100% using saliva and DBS in HIV monoinfected and control subjects. When only anti-HCV/HCV RNA+ serum samples, that is, true positives, were considered, the sensitivities were 98.3% and 100% for DBS and saliva, respectively, in the HCV+ group and 91.6% and 94.8% for DBS and saliva, respectively, in the HIV/HCV+ group. High absorbance values were observed among those presenting with HCV RNA in serum and low HIV viral load (less than 50 copies/mL). In conclusion, DBS and saliva samples could be used for anti-HCV detection, particularly to identify active HCV cases, but low sensitivity was observed for anti-HCV testing using DBS in the HIV/HCV+ group.

High prevalence of insulin resistance among Brazilian chronic hepatitis C patients.

OBJECTIVE: This study aims to estimate the prevalence of insulin resistance (IR) among chronic hepatitis C (CHC) patients and their related laboratory and demographic data. SUBJECTS AND METHODS: In this study, non-diabetic CHC patients referred to Viral Hepatitis Ambulatories from Rio de Janeiro (Brazil) donated blood samples. Insulin was measured using a chemiluminescence immunoassay. IR was determined by HOMA-IR, where HOMA-IR > 2 was defined as IR. RESULTS: A total of 214 CHC patients were recruited (123 females aged 53.6 years ± 10.9 years). IR was present in 133 patients (62.1%) and was associated in bivariate analysis to higher mean values of age (p = 0.040), triglycerides (p = 0.032), glucose (p = 0.000), insulin (p = 0.000), waist circumference (p = 0.001), and body mass index (p = 0.007); however, none of these variables were significant in the multivariate analysis. CONCLUSIONS: The high prevalence of IR was observed among CHC patients, and there was no difference in clinical or laboratory parameters when both groups were compared in the multivariate analysis. This high IR prevalence could lead to a high risk for development of cardiovascular disease and metabolic disorders.

Evaluation of dried blood spot samples for hepatitis C virus detection and quantification.

BACKGROUND: Dried blood spots (DBS) could be an excellent alternative for HCV diagnosis, since it is less invasive and can be stored and transported without refrigeration. OBJECTIVES: The aim of this study was to optimize quantitative and qualitative methods for HCV detection in DBS. STUDY DESIGN: DBS and serum samples were collected from 99 subjects (59 anti-HCV/HCV RNA positive and 40 seronegative samples). Seven extraction methods and different PCR parameters were evaluated in DBS samples in the quantitative RT-PCR (qRT-PCR) developed to amplify the 5' noncoding region of HCV. A qualitative PCR for amplification of NS5B region of HCV was also valued and the nested-PCR sequenced. RESULTS: The qRT-PCR showed good correlation to commercial assay for HCV viral measurement in serum. To quantify HCV RNA in DBS, it was necessary to increase reverse transcriptase and cDNA concentration. HCV RNA quantification in DBS demonstrated sensitivity of 65.9%, 100% of specificity and kappa statistic of 0.65. The median viral load of DBS samples was 5.38 log10 copies/ml (minimum value=1.76 and maximum value=10.48 log10 copies/ml). HCV RNA was detected in NS5B regions and nucleotide sequences obtained in 43 serum and 11 DBS samples. The presence of the same subtype was observed in paired serum and DBS samples. CONCLUSIONS: In this study, it was possible to demonstrate that, despite the low sensitivity, the optimized protocol was able to determine the viral load, as well as, the infecting HCV genotype, validating the usefulness of DBS for viral load determination and molecular epidemiology studies of HCV.

Performance of rapid hepatitis C virus antibody assays among high- and low-risk populations.

BACKGROUND: Rapid tests for the detection of antibodies to hepatitis C virus (anti-HCV) can facilitate access to diagnosis. OBJECTIVES: This study aimed to evaluate the performance of rapid tests for anti-HCV detection in the sera, whole blood, and oral fluid samples from individuals with different endemicity profiles and risk behaviors. STUDY DESIGN: Three groups donated biological samples that were tested using three anti-HCV rapid tests (WAMA, Bioeasy and OraSure): (I) suspected cases of hepatitis C, (II) individuals who were living in remote areas in Brazil and (III) crack users and beauty professionals. Reproducibility, repeatability and cross-reactivity to other infectious agents (dengue, HIV, malaria, and syphilis) were also evaluated. RESULTS: In group I, specificities varied from 93.75% to 100% and sensitivities varied from 76.03% to 93.84% according to the EIA results. When anti-HCV/HCV RNA-reactive sera samples were considered true-positive HCV cases, the sensitivities and specificities varied from 86.3% to 99.09% and 93.75% to 100%, respectively. In group II, the OraSure rapid test presented the best performance. In group III, the Bioeasy assay performed best using saliva and whole blood and the OraSure assay performed best using oral fluid samples. The reproducibility and repeatability of the WAMA and Bioeasy tests were excellent. The level of concordance between the HCV EIAs and the rapid tests using samples that were reactive for other infectious agents varied from 82.35% to 100% for the WAMA assay and 94.11% to 100% for the Bioeasy assay. CONCLUSION: All of the rapid tests could be used to identify active HCV infection among individuals with different endemicity profiles and risk behaviors.

Analysis of hepatitis C virus (HCV) RNA load in platelets of HCV-monoinfected patients receiving antiviral therapy.

INTRODUCTION: Detection of hepatitis C virus (HCV) has been reported in extrahepatic sites such as peripheral blood mononuclear cells and platelets. Quantitation of HCV-RNA in platelets from patients under antiviral therapy has not been reported. MATERIAL AND METHODS: HCV-RNA levels in paired serum and platelet samples of 17 chronically HCV-infected patients were determined at baseline, week 12, end-of-treatment, and 24 weeks after completion of treatment with pegylated interferon plus ribavirin. Quantitation of HCVRNA load was performed using COBAS® TaqMan® HCV Test v 2.0 (lower limit of detection, 25 IU/mL). The cohort predominantly consisted of female (59%) with a mean age of 50.7 ± 10.0 years. RESULTS: Measurements of HCV-RNA in relation to different timepoints of therapy revealed baseline viral load was most frequently detected in higher levels in serum than in platelets (5.6 x 104 IU/mL vs. 379.0 IU/mL; p = 0.0002), a trend also demonstrated in most samples throughout the study. HCV-RNA was also found at low levels (< 25.0-314.0 UI/mL) persistently in platelets of three patients who have lost detectable HCV-RNA in serum during antiviral therapy, resulting in virological relapse. CONCLUSION: HCV-RNA levels are most frequently detected in higher levels in serum than in platelets, independent of timepoint of antiviral therapy. Further studies with an increase in size of the samples are needed to better evaluate whether or not patients who presented HCV-RNA at low levels in platelets after having lost detectable HCV-RNA in serum during antiviral therapy are at increased risk of relapse of HCV infection during follow-up evaluation.

Prevalência de anticorpos anti-vírus da hepatite D (HDV) em pacientes com hepatite B no Rio de Janeiro e caracterização molecular do genoma completo do HDV / Prevalence of antibodies to hepatitis D virus (HDV) in patients with hepatitis B in Rio de Janeiro and molecular characterization of the complete genome of HDV

O vírus da hepatite D (Hepatitis D Virus ou HDV) é um vírus defectivo que necessita da presença do vírus da hepatite B (HBV) para completar seu ciclo infeccioso. A infecção pelo HDV está associada a uma forma mais grave de hepatite e com aumento do risco de progressão para complicações, tais como, cirrose e carcinoma hepatocelular. No Brasil, a Bacia Amazônica é uma área endêmica para a infecção pelo HDV, no entanto, poucos dados foram avaliados em outras regiões do país. Este estudo avaliou a prevalência de HDV em pacientes com infecção aguda ou crônica pelo HBV, acompanhados no Ambulatório Hepatites Virais, Rio de Janeiro, Brasil, entre 2006 e 2011. Um total de 368 amostras de soro de pacientes positivos para o antígeno de superfície do vírus da hepatite B (HBsAg) foi testado para a presença de anticorpos anti-HD utilizando o ensaio comercial ETI-AB-DELTAK-2, de acordo com as instruções do fabricante. Amostras com resultados reagentes ou indeterminados foram retestadas em duplicata, para confirmação ou não do resultado. Amostras anti-HD positivos foram testadas por PCR para amplificar um fragmento da região genômica do antígeno delta (HDAg). As amostras positivas para HDV RNA foram submetidas ao sequenciamento de nucleotídico, a fim de identificar o genótipo do HDV. As sequências obtidas foram alinhadas utilizando o programa Clustal X e a análise filogenética foi realizada usando o programa MEGA v.5. A carga viral do HBV foi quantificada por meio do ensaio comercial COBAS ® TaqMan ® HBV e o genótipo do HBV foi determinado pelo ensaio INNO-LIPA. Nossa população de estudo consistiu de 243 homens e 125 mulheres, com média de idade de 43 anos (1-82 anos), sendo 138 e 230 pacientes com infecção aguda e crônica pelo HBV, respectivamente. Cinco pacientes foram positivos para anticorpos anti-HD (infecção aguda pelo HBV, n = 1; infecção crônica pelo HBV, n = 4) e um dos pacientes com infecção crônica pelo HBV apresentou amostras com HDV RNA detectável. A análise filogenética mostrou que a sequência do HDV se agrupou com o genótipo 3. Dos quatro pacientes que tiveram HBV DNA detectado, três apresentaram baixos níveis de HBV DNA. Em relação ao genótipo de HBV, o genótipo A foi mais prevalente (n = 4). A fim de caracterizar a variabilidade genética de todo o genoma de HDV, o genoma completo foi sequenciado e as sequências de aminoácidos deduzidas foram inferidas utilizando o programa MEGA v.5. O genoma da amostra identificado no presente estudo é constituído por 1673 nucleotídeos e mostrou apenas 88,7% de similaridade com as sequências de genótipo 3 caracterizadas até o momento. A região LHDAg (large HDAg) da amostra brasileira contém múltiplas substituições de aminoácidos, que são conservadas em todas as sequências completas de genótipo 3, cujo significado ainda não foi estabelecido. Este trabalho constitui o primeiro estudo sobre a caracterização da variabilidade genética do genoma completo do HDV no Brasil. Em conclusão, apesar da soroprevalência de HDV ser considerada baixa em nossa coorte, este resultado destacou a importância da investigação infecção pelo HDV em áreas não endêmicas.

Investigação dos efeitos do extrato bruto de Tabebuia avellanedae e do principio ativo isolado 'beta'-Lapachona sobre alguns parametros imunologicos em camundongos portadores do tumor ascitico de Ehrlich / Tabebuia avellanedae crude extract and 'beta-Lapachone induced anti-tumor response in Erhrlich tumor-bearing mice

Com os recentes progressos na compreensão dos complexos mecanismos moleculares relacionados a diferentes aspectos da modulação imunológica, cada vez mais vem se tornando possível ampliar os conhecimentos acerca das potenciais interferências do ponto de vista imunopatogênico induzidas pela presença e evolução tanto de processos infecciosos quanto tumorais. Modelos experimentais vêm sendo desenvolvidos e aprimorados com a finalidade de criar condições controladas para avaliações de diferentes aspectos relativos a potenciais modificações no comportamento imunológico de linhagens celulares frente à ação de novos agentes. O modelo do Tumor Ascítico de Erlich apresentou-se como uma opção de interesse, uma vez que os conhecimentos experimentais sobre diferentes aspectos relativos a sua manipulação já fazem parte de consagrada linha de pesquisa nacional. Um dos comportamentos mais recentemente estudados a seu respeito se refere a condições onde ocorre a migração do fenótipo Th1 para Th2, relacionadas ao agravamento da doença. A busca de fontes naturais para conhecimento e aplicação de novos princípios ativos vem se caracterizando como uma das mais promissoras soluções do ponto de vista farmacêutico, e pode corresponder a uma importante área de exploração da biodiversidade nacional. Dessa forma, a proposta do presente estudo foi, unindo linhas de pesquisa bastante consolidadas e conhecimentos relativos à nossa biodiversidade, avaliar o potencial terapêutico, com foco em abordagens imunopatológicas, do extrato da planta Tabebuia avellanedae (ETA) através do modelo experimental Tumor ascítico de Ehrlich. Neste trabalho investigamos os efeitos do ETA e...

In accordance with the recent progress in the understanding of immunological and molecular mechanisms related to the different aspects of immunological modulation, the improvement of knowledge about the potential interferences, at the immunopathogenic point of view, induced by the presence and evolution of infectious diseases or neoplastic process has increased. Experimental models have been developed and refined in order to create appropriate conditions to evaluate different aspects related to potential changes in the immunological behaviors of determinate cell lines with the presence of new pharmacological agents. The Ehrlich ascites tumor (EAT) model is an option of interest, since the accumulated experimental knowledge about its manipulation is part of a consolidated research line. One of its more recently studied behaviors is concerned with situations where the migration from Th1 to Th2 phenotype occurs, at the same time with the disease impairment. The search for new natural sources of pharmaceutical active principles and the careful and detailed studies about them, has been characterized as one of most promising therapeutic solutions at the moment, and would be seen as a strategic way to explore the national biodiversity. Therefore, the aim of the present study was to combine the well known techniques related to the Ehrlich ascites tumor changing behavior with a potential active principle from our botanical biodiversity, the Tabebuia avellanedae extract (TACE), in order to evaluate its immunological therapeutic potential. The effects of TACE and its isolated naphtoquinone...