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ABSTRACT Background: Leprosy is a neglected dermato-neurologic, infectious disease caused by Mycobacterium leprae or M. lepromatosis. Leprosy is treatable and curable by multidrug therapy/MDT, consisting of 12 months rifampicin, dapsone and clofazimine for multibacillary/MB patients and for 6 months for paucibacillary/PB patients. The relapse rate is considered a crucial treatment outcome. A randomized Controlled Clinical Trial (U-MDT/CT-BR) conducted from 2007‒2012 compared clinical outcomes in MB patients after 12 months regular MDT/R-MDT and 6 months uniform MDT/U-MDT in two highly endemic Brazilian areas. Objectives: To estimate the 10 years relapse rate of MB patients treated with 6 months U-MDT. Methods: The statistical analyses treated the data as a case-control study, sampled from the cohort generated for the randomized trial. Analyses estimated univariate odds ratio and applied logistic regression for multivariate analysis, controlling the confounding variables. Results: The overall relapse rate was 4.08 %: 4.95 % (16 out of 323) in the U-MDT group and 3.10 % (9 out of 290) in the regular/R-MDT group. The difference in relapse proportion between U-MDT and R-MDT groups was 1.85 %, not statistically significant (Odds Ratio = 1.63, 95 % CI 0.71 to 3.74). However, misdiagnosis of relapses, may have introduced bias, underestimating the force of the association represented by the odds ratio. Conclusions: The relapse estimate of 10 years follow-up study of the first randomized, controlled study on U-MDT/CT-BR was similar to the R-MDT group, supporting strong evidence that 6 months U-MDT for MB patients is an acceptable option to be adopted by leprosy endemic countries worldwide. Trial registration: ClinicalTrials.gov: NCT00669643.
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ABSTRACT Homeless people are at high risk for sexually transmitted infections (STIs), such as human immunodeficiency virus (HIV) infection and syphilis. We investigated the epidemiology of HIV-1 infection and syphilis among homeless individuals in a large city in Central-Western Brazil. In this cross-sectional study, we interviewed and tested 355 individuals from September 2014 to August 2015. Rapid test samples positive for syphilis were retested using the Venereal Disease Research Laboratory (VDRL) test. Blood samples from HIV-infected participants were collected for POL sequencing using HIV-1 RNA extracted from plasma, reverse transcription, and nested polymerase chain reaction. Anti-HIV-1-positive samples were subtyped by sequencing the nucleotides of HIV-1 protease and part of the HIV-1 reverse transcriptase genes. Transmitted and acquired drug resistance mutations and susceptibility to antiretroviral drugs were also analyzed. Anti-HIV was positive in 14 patients (3.9%; 95% confidence interval [CI]: 2.3-6.4). HIV-1 RNA was detected in 8 of the 14 samples. Two of the eight (25%) isolates showed HIV-1 drug resistance mutations. Furthermore, 78 (22%; 95% CI: 17.9-26.5) and 29 (8.2%; 95% CI: 5.6-11.4) homeless individuals tested positive for syphilis using the rapid test and VDRL test, respectively. Two individuals were anti-HIV-1 and VDRL test positive. Daily alcohol use (adjusted odds ratio [AOR]: 3.2, 95% CI: 1.0-10.4), sex with people living with HIV (PLWH) infection (AOR: 6.8, 95% CI: 1.9-25.0), and sex with people of the same sex (AOR: 5.4, 95% CI: 1.7-17.5) were predictors of HIV infection. Age ≤35 years (AOR: 3.8, 95% CI: 1.4-10.8), previous syphilis testing (AOR: 3.5, 95% CI: 1.4-8.4), history of genital lesions (AOR: 4.9, 95% CI: 1.3-19.1), and crack use in the last six months (AOR: 3.1, 95% CI: 1.3-7.6) were predictors of syphilis. Our findings highlight the importance of STI prevention and control strategies among the homeless.
Subject(s)
Syphilis/epidemiology , HIV Infections/epidemiology , HIV-1/genetics , Genetic Variation , Brazil/epidemiology , Drug Resistance , Prevalence , Cross-Sectional Studies , Risk Factors , MutationABSTRACT
ABSTRACT Brazil is a huge continental country with striking geographic differences which are well illustrated in the HIV/AIDS epidemic. Contrasting with the significant decline in the national AIDS detection rate in the last decade, a linear growth has been reported in the Northern region. Despite its public health and epidemiologic importance, there is scarce HIV-1 molecular data from Northern Brazil. This scoping review summarizes recent epidemiologic data with special emphasis on HIV-1 genetic diversity and antiretroviral drug resistance mutations in patients from the seven Northern states of Brazil. Studies from the Northern Brazil on different HIV-1 genomic regions, mostly pol (protease/reverse transcriptase) sequences of naïve/antiretroviral treated adults/children were retrieved from PubMed/MEDLINE electronic database. These studies indicate a consistent molecular profile largely dominated by HIV-1 subtype B with minor contribution of subtypes F1 and C and infrequent detection of other subtypes (A1, D, K), recombinants (BF1, BC), circulating recombinant forms (CRF) as the new CRF90_BF1 and CRF02_AG-like, CRF28-29_BF-like, CRF31_BC-like, and a potential new CRF_BF1. This pattern indicates a founder effect of subtype B and the introduction of non-B-subtypes and recombinants probably generated in the Southern/Southeastern regions. In naïve populations transmitted drug resistance (TDR) can impact the outcome of first-line antiretroviral treatment and prophylactic/preventive regimens. In the Northern region TDR rates are moderate while patients failing highly active antiretroviral therapy (HAART) showed high prevalence of acquired drug resistance mutations. The limited HIV-1 molecular data from Northern Brazil reflects the great challenges to generate comprehensive scientific data in isolated, underprivileged areas. It also highlights the need to invest in local capacity building which supported by adequate infrastructure and funding can promote robust research activities to help reduce the scientific asymmetries in the Northern region. Currently the impacts of the overwhelming COVID-19 pandemic on the expanding HIV/AIDS epidemic in Northern Brazil deserves to be closely monitored.
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Humans , HIV Infections/drug therapy , HIV Infections/epidemiology , HIV-1/genetics , COVID-19 , Phylogeny , Brazil , Drug Resistance , Sequence Analysis, DNA , Drug Resistance, Viral/genetics , Pandemics , SARS-CoV-2 , Genotype , MutationABSTRACT
Abstract: BACKGROUND: The Clinical Trial for Uniform Multidrug Therapy for Leprosy Patients in Brazil (U-MDT/CT-BR), designed to evaluate the effectiveness of a six-months regimen, assessed the adverse effects caused by the drugs. OBJECTIVE: Describe adverse effects due to MDT in U-MDT/CT-BR, comparing the uniform regimen (U-MDT) to the current WHO regimen (R-MDT). Patients and methods: After operational classification, patients were randomly allocated to the study groups. U-MDT PB and U-MDT MB groups, received the U-MDT regimen, six doses of MB-MDT (rifampicin, dapsone and clofazimine). R-MDT PB and R-MDT MB groups, received the WHO regimens: six doses (rifampicin and dapsone) for PB and 12 doses (rifampicin, dapsone and clofazimine) for MB. During treatment, patients returned monthly for clinical and laboratorial evaluation. Patients with single lesion were not included in this trial. RESULTS: Skin pigmentation (21.7%) and xerosis (16.9%) were the most frequent complaints among 753 patients. Laboratory exams showed hemoglobin concentration lower than 10g/dL in 23.3% of the patients, glutamic oxaloacetic transaminase (GOT) above 40U/L in 29.5% and glutamic pyruvic transaminase (GPT) above 40U/L in 28.5%. Twenty-four patients (3.2%) stopped dapsone intake due to adverse effects, of whom 16.6% due to severe anemia. One case of sulfone syndrome was reported. STUDY LIMITATIONS: Loss of some monthly laboratory sample collection. CONCLUSIONS: There was no statistical difference regarding adverse effects in the R-MDT and U-MDT groups but anemia was greater in patients from R-MDT/MB group, therefore adverse effects do not represent a constraint to recommend the six-month uniform regimen of treatment for all leprosy patients.
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Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Young Adult , Rifampin/adverse effects , Clofazimine/adverse effects , Dapsone/adverse effects , Leprostatic Agents/adverse effects , Rifampin/administration & dosage , Brazil , Hemoglobins/analysis , Risk Factors , Treatment Outcome , Clofazimine/administration & dosage , Dapsone/administration & dosage , Drug Therapy, Combination/adverse effects , Anemia/chemically induced , Anemia/blood , Leprostatic Agents/administration & dosage , Leprosy/complications , Leprosy/drug therapy , Leprosy/bloodABSTRACT
New Mycobacterium leprae protein antigens can contribute to improved serologic tests for leprosy diagnosis/classification and multidrug therapy (MDT) monitoring. This study describes seroreactivity to M. leprae proteins among participants from three highly endemic leprosy areas in Brazil: central-western Goiânia/Goiás (GO) (n = 225), Rondonópolis/Mato Grosso (MT) (n = 764) and northern Prata Village/Pará (PA) (n = 93). ELISA was performed to detect IgG to proteins (92f, 46f, leprosy IDRI diagnostic-1, ML0405, ML1213) and IgM to phenolic glycolipid-I (PGL-I). Multibacillary (MB) leprosy had positive rates for PGL-I that were similar to those for proteins; however, some anti-PGL-I-negative subjects were positive for proteins, suggesting that adding protein antigen to PGL-I can enhance the sensitivity of MB leprosy detection. In MT, different degrees of seroreactivity were observed and ranked for MB, former patients after MDT, paucibacillary (PB) leprosy, household contact (HHC) and endemic control (EC) groups. The seroreactivity of PB patients was low in GO and MT. HHCs from different endemic sites had similar IgG antibody responses to proteins. 46f and 92f were not recognised by most tuberculosis patients, ECs or HHCs within GO, an area with high BCG vaccination coverage. Low positivity in EC and HHC was observed in PA and MT. Our results provide evidence for the development of an improved serologic test that could be widely applicable for MB leprosy testing in Brazil.
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Adult , Female , Humans , Male , Antibodies, Bacterial/blood , Antigens, Bacterial/blood , Bacterial Proteins/blood , Endemic Diseases , Glycolipids/blood , Leprosy/diagnosis , Mycobacterium leprae/immunology , Brazil/epidemiology , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Immunoglobulin M/blood , Leprosy/epidemiologyABSTRACT
The diagnosis of leprosy continues to be based on clinical symptoms and early diagnosis and treatment are critical to preventing disability and transmission. Sensitive and specific laboratory tests are not available for diagnosing leprosy. Despite the limited applicability of anti-phenolic glycolipid-I (PGL-I) serology for diagnosis, it has been suggested as an additional tool to classify leprosy patients (LPs) for treatment purposes. Two formats of rapid tests to detect anti-PGL-I antibodies [ML immunochromatography assay (ICA) and ML Flow] were compared in different groups, multibacillary patients, paucibacillary patients, household contacts and healthy controls in Brazil and Nepal. High ML Flow intra-test concordance was observed and low to moderate agreement between the results of ML ICA and ML Flow tests on the serum of LPs was observed. LPs were "seroclassified" according to the results of these tests and the seroclassification was compared to other currently used classification systems: the World Health Organization operational classification, the bacilloscopic index and the Ridley-Jopling classification. When analysing the usefulness of these tests in the operational classification of PB and MB leprosy for treatment and follow-up purposes, the ML Flow test was the best point-of-care test for subjects in Nepal and despite the need for sample dilution, the ML ICA test yielded better performance among Brazilian subjects. Our results identified possible ways to improve the performance of both tests.
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Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Antigens, Bacterial/blood , Glycolipids/blood , Immunoglobulin Isotypes/blood , Leprosy/diagnosis , Mycobacterium leprae/immunology , Brazil , Case-Control Studies , Immunoassay/methods , Chromatography, Affinity/methods , Leprosy/immunology , Nepal , Predictive Value of Tests , Reagent Kits, Diagnostic , Sensitivity and SpecificityABSTRACT
New Mycobacterium leprae protein antigens can contribute to improved serologic tests for leprosy diagnosis/classification and multidrug therapy (MDT) monitoring. This study describes seroreactivity to M. leprae proteins among participants from three highly endemic leprosy areas in Brazil: central-western Goiânia/Goiás (GO) (n = 225), Rondonópolis/Mato Grosso (MT) (n = 764) and northern Prata Village/Pará (PA) (n = 93). ELISA was performed to detect IgG to proteins (92f, 46f, leprosy IDRI diagnostic-1, ML0405, ML1213) and IgM to phenolic glycolipid-I (PGL-I). Multibacillary (MB) leprosy had positive rates for PGL-I that were similar to those for proteins; however, some anti-PGL-I-negative subjects were positive for proteins, suggesting that adding protein antigen to PGL-I can enhance the sensitivity of MB leprosy detection. In MT, different degrees of seroreactivity were observed and ranked for MB, former patients after MDT, paucibacillary (PB) leprosy, household contact (HHC) and endemic control (EC) groups. The seroreactivity of PB patients was low in GO and MT. HHCs from different endemic sites had similar IgG antibody responses to proteins. 46f and 92f were not recognised by most tuberculosis patients, ECs or HHCs within GO, an area with high BCG vaccination coverage. Low positivity in EC and HHC was observed in PA and MT. Our results provide evidence for the development of an improved serologic test that could be widely applicable for MB leprosy testing in Brazil
Subject(s)
Humans , Male , Female , Adult , Antibodies, Bacterial/blood , Antigens, Bacterial/blood , Endemic Diseases , Glycolipids/blood , Leprosy/diagnosis , Leprosy/epidemiology , Mycobacterium leprae/immunology , Bacterial Proteins/blood , Brazil/epidemiology , Enzyme-Linked Immunosorbent Assay , Case-Control Studies , Immunoglobulin M/bloodABSTRACT
INTRODUCTION: Among HIV-1-infected patients, CD4+ T cell counts are well-established markers of cell-mediated immunity. Delayed-type hypersensitivity (DTH) skin tests can be used to evaluate in vivo cell-mediated immunity to common antigens. METHODS: DTH responses to tuberculin purified protein derivative (PPD), sporotrichin, trichophytin, candidin and streptokinase/streptodornase antigens were assessed. Thirty-six HIV-1-infected children/adolescents and 56 age- and sex-matched HIV-1/HIV-2-seronegative participants were tested. All participants had a BCG scar. Fisher's exact test was used to evaluate significant differences between groups (p<0.05). RESULTS: The main characteristics of the HIV-1 patients were as follows: median age 8.1 years; 20/36 were males; 35 were vertical transmission cases; 34 were AIDS cases under antiretroviral therapy; median viral load = 3.04 log10 copies/ml; median CD4+ T cell count = 701 cells/μl. A total of 25 percent (9/36) and 87.5 percent (49/56) of HIV-1-infected and healthy participants, respectively, displayed DTH reactivity to at least one antigen (p<0.001). Among HIV-1-infected participants, reactivity to candidin predominated (8/36, 22.2 percent), while PPD positivity prevailed among healthy participants (40/56, 71.4 percent). PPD reactivity in the HIV-1-positive group was 8.3 percent (p<0.01). The median PPD induration was 2.5mm (range: 2-5mm) in the HIV-1 group and 6.0 mm among healthy participants (range: 3-15mm). There was no correlation between PPD positivity and age. No correlation between CD4+ T cell counts and DTH reactivity was observed among HIV-1-infected patients. CONCLUSIONS: DTH skin test responses, including PPD reactivity, were significantly lower among HIV-1-infected participants compared to healthy controls, which likely reflects advanced disease and T cell depletion.
INTRODUÇÃO: A contagem de células CD4+ representa marcador da resposta imune celular em pacientes infectados pelo HIV-1. Testes cutâneos de hipersensibilidade tardia (DTH) podem ser empregados para avaliar in vivo respostas celulares a antígenos comuns. MÉTODOS: DTH para derivado proteico purificado de tuberculina (PPD), esporotriquina, tricofitina, candidina e estreptoquinase/estreptodornase foram realizados. Foram testados crianças/adolescentes infectados pelo HIV-1 (n=36) e indivíduos saudáveis (n=56), soronegativos para HIV-1/HIV-2 pareados por sexo-idade, todos com cicatriz vacinal por BCG. Teste exato de Fisher foi aplicado (p<0,05). RESULTADOS: Entre as crianças/adolescentes infectados pelo HIV-1, mediana de idade=8,1 anos; 20/36 eram do sexo masculino; 35 casos de transmissão vertical; 34 casos de AIDS sob terapia antirretroviral; mediana de carga viral = 3.04lc10 cópias/ml; mediana de contagem de células CD4+ = 701 células/μl. Entre os infectados e saudáveis a reatividade DTH a pelo menos um dos antígenos foi, respectivamente, 25 por cento (9/36) e 87,5 por cento (49/56) (p<0,001). Reatividade à candidina predominou nos infectados (8/36, 22 por cento) e ao PPD nos indivíduos saudáveis (40/56, 71,4 por cento). A reatividade ao PPD entre infectados foi de 8,3 por cento (p<0,01). A mediana da induração ao PPD foi 2,5mm (variação: 2-5mm) entre infectados e 6,0mm (variação: 3-15mm) entre os saudáveis. Não observamos correlação entre positividade ao PPD e idade. No grupo de infectados, não observamos correlação entre contagens de células CD4+ e reatividade ao DTH. CONCLUSÕES: Respostas DTH significativamente diminuídas, incluindo a reatividade ao PPD foram observadas em crianças/adolescentes infectados pelo HIV-1 comparadas com controles saudáveis, provavelmente refletindo doença avançada e supressão da imunidade mediada por células T.
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Male , Antigens, Bacterial/immunology , HIV Infections/immunology , Hypersensitivity, Delayed/immunology , Intradermal Tests/methods , Adjuvants, Immunologic/administration & dosage , Antigens, Bacterial , BCG Vaccine/administration & dosage , Case-Control Studies , HIV Infections/virology , Prospective Studies , Viral LoadABSTRACT
O diagnóstico da hanseníase se baseia em manifestações clínicas e não existe teste laboratorial para diagnosticar casos assintomáticos ou para prever progressão da doença entre indivíduos expostos. Novas análises genômicas comparativas in silico e ferramentas de biologia molecular têm sido empregadas para revelar proteínas exclusivas do Mycobacterium leprae que apresentem potencial aplicação diagnóstica. A hanseníase tuberculóide paucibacilar (PB) apresenta baixo nível de anticorpos e forte resposta imune celular (RIC) tipo Th1/interferon gamma (IFN-γ). A doença lepromatosa multibacilar (MB) apresenta sorologia positiva e fraca RIC. Portanto, testes laboratoriais para diagnosticar hanseníase PB e MB devem contemplar testes de RIC e sorologia. Proteínas recombinantes do Mycobacterium leprae sorologicamente reativas podem ser incorporadas ao antígeno PGLI para melhorar o diagnóstico sorológico de pacientes MB. Proteínas recombinantes e peptídeos sintéticos do Mycobacterium leprae têm sido testados em ensaios de RIC/IFN-γ para diagnosticar casos PB. Sorologia anti-PGLI modificada incorporando novos antígenos do Mycobacterium leprae e ensaios baseados na RIC/produção de IFN-γ devem permitir a detecção precoce de casos MB e PB em países endêmicos.
Leprosy diagnosis is based mainly on clinical manifestations and no laboratory test is available to diagnose asymptomatic disease or to predict disease progression among exposed individuals. Novel comparative genomic in silico analyses and molecular biology tools have discovered unique Mycobacterium leprae proteins with potential diagnostic application. Tuberculoid paucibacillary leprosy (PB) shows low antibodies titers and strong Th1 type/ IFN-γ specific cell mediated immunity (CMI), while lepromatous multibacillary patients (MB) show high antibody titers and low CMI. Therefore, laboratory tests for PB and MB leprosy diagnosis will require CMI and antibody based assays. Serologically reactive recombinant Mycobacterium leprae proteins were identified and may be used in conjunction with PGL-I to improve MB patient diagnosis. Mycobacterium leprae recombinant proteins and synthetic peptides have been tested for CMI-interferon gamma based assays for PB diagnosis. Modified PGL-I serology incorporating new Mycobacterium leprae antigens and CMI tests based on IFN-γ γ production may permit the detection of leprosy PB and MB forms in endemic countries.
Subject(s)
Humans , Leprosy, Lepromatous/diagnosis , Leprosy, Tuberculoid/diagnosis , Mycobacterium leprae/genetics , Antigens, Bacterial , Glycolipids , Immunity, Cellular/immunology , Interferon-gamma/immunology , Leprosy, Lepromatous/immunology , Leprosy, Tuberculoid/immunology , Mycobacterium leprae/immunology , Polymerase Chain Reaction , Th1 Cells/immunologyABSTRACT
A endemia hansênica apresenta-se, na virada do milênio, no limiar da sua eliminaçäo como problema global de saúde pública. O Brasil é o único país da América Latina onde a doença näo foi eliminada, tendo sido a meta de eliminaçäo postergada para 2005. Discute-se o declínio da prevalência após a introduçäo da poliquimioterapia (PQT) para o tratamento da hanseníase, näo acompanhada pela reduçäo da incidência no mesmo período. Os progressos na área de imunologia, biologia molecular e sequenciamento genômico do M leprae säo apresentados enquanto perspectivas de pesquisa e de aplicaçäo potencial para diagnóstico, prognóstico e vigilância na hanseníase. Apesar do êxito das atuais estratégias de controle tem-se observado com preocupaçäo a reduçäo do interesse e do apoio financeiro em pesquisa na hanseníase e na desestruturaçäo dos serviços de saúde frente ao atual cenário de eliminaçäo. A exclusäo da hanseníase da lista de doenças prioritárias é prematura, representando um perigo concreto de näo se eliminar a doença, mas a pesquisa em hanseníase. Fica evidente a necessidade de investigar na produçäo de conhecimentos de áreas básicas e aplicada que viabilizem uma maior compreensäo dos mecanismos de transmissäo da infecçäo, da efetividade dos métodos de prevençäo e controle, seräo essenciais na ôerradicaçäoö da infecçäo pelo M leprae
Subject(s)
Disease Outbreaks , Endemic Diseases , LeprosyABSTRACT
Neste trabalho sä revisadas as evidências sobre a interaçäo entre a infecçäo pelo HIV/aids e a hanseníase em consonância com os programas de controle e o desenvolvimento de pesquisas na duas últimas décadas. Säo apresentadas hipóteses e questöes suscitadas pelo possível efeito da co-infecçäo pelo HIV e Mycobacterium leprae alterar o curso de cada infecçäo/doença e desenvolver casos mais graves. Aspectos relacionados à interaçäo adversa entre as terapêuticas pdronizadas, quanto aplicadas simultaneamente para ambas infecçöes/doenças, e as implicaçöes na vacinaçäo BCG nos países em desenvolvimento säo também examinados. A interaçäo entre aids e tuberculose foi usada como exemplo de uma bem conhecida interaçäo biológica entre infecçäo pelo HIV e doenças infecciosas e para traçar um paralelo com outras micobactérias.
Subject(s)
Humans , Mycobacterium leprae , Leprosy/etiology , HIV Infections/epidemiology , Nontuberculous Mycobacteria , Acquired Immunodeficiency Syndrome/complications , Brazil/epidemiology , Leprosy/epidemiology , Leprosy/drug therapy , Acquired Immunodeficiency Syndrome/epidemiology , Acquired Immunodeficiency Syndrome/drug therapyABSTRACT
O Organizaçäo Mundial da Saúde(OMS) estima que um terço da populaçäo mundial esteja infectada por Mycobacterium tuberculosis, agente etiológico da tuberculose(TB. Cerca de 3 milhöes de óbitos anuais ocorrem devido à TB, contabilizando isoladamente um número de mortes superior a qualquer outro agente infeccioso. Apesar da disponibilidade da vacina do Bacilo Calmette-Guérin (BCG) e da implementaçäo da terapia supervisionada de curta duraçäo (DOTS) em várias regiöes do mundo, TB aparece como uma grave complicaçäo da infecçäo pelo Vírus da Imonodeficiência Humana (HIV), tanto em países em desenvolvimento como em países industrializados. Os macrófagos representam as principais células efetoras na eliminaçäo do bacilo e säo infectados pelo M.tuberculosis por múltiplos mecanismos. Como umm patógeno intracelular, a resposta imune protetora é medida por células (CMI) e dependente da ativaçäo do macrófago por citocinas do tipo 1, especialmente interferon-y (IFN-y). A produçäo de IFN-y ocorre principalmente pelo linfócito T CD4+ em resposta à interleucina-12, produzida pelo macrófago...
Subject(s)
Humans , Tuberculosis/etiology , HIV/immunology , Mycobacterium tuberculosis/immunology , Acquired Immunodeficiency Syndrome/complicationsABSTRACT
Esta revisäo aborda recentes descobertas dque esclareceram a natureza das moléculas acessórias obrigatoriamente utilizadas pelo HIV para infectar células humanas, elucidando mecanismos de resistência à infecçäo e abrindo perspectivas de novos alvos para drogas e vacinas. Um ano após a descoberta do HIV, a molécula CD4 foi identificada como receptor primário utilizado no processo de infecçäo dos linfócitos T. Entretanto, há mais de uma década se sabia que só esta molécula näo era suficiente e que o HIV precisava de moléculas adicionais, ou co-receptores, para permitir a infecçäo da célula-alvo. Em 1996, vários grupos de pesquisa descobriram que receptores para citocinas, das quais bem caracterizadas...