ABSTRACT
Human T-lymphotropic virus type 1 (HTLV-1) infection is an important health issue that affects a variety of endemic areas. The Khorasan province, mainly its capital Mashhad in northeastern Iran, was reported to be as one of these endemic regions. Torbat-e Heydarieh, a large city Southwest border to Mashhad with a segregated population was investigated for the prevalence and associated risk factors of HTLV-1 infection in 400 randomly selected individuals. Blood samples were tested for the presence of HTLV-1 antibodies via the ELISA method and then were confirmed by an Immunoblot test. For the presence of HTLV-1 in lymphocytes of infected subjects, PCR was performed on LTR and TAX regions. DNA sequencing of LTR fragment was also carried out to determine the phylogenetic of HTLV-1, using the Maximum likelihood method. HTLV-1 sero-reactivity (sero-prevalence) among the study population was 2% (8/400), of which 1.25% had HTLV-1 provirus in lymphocytes (actual prevalence). HTLV-1 infection was significantly associated with the age, marital status, and history of blood transfusion (P < 0.05). However, there were no statistical differences between HTLV-1 infection, and gender, surgery, and hospitalization. In regression analysis, age showed the most significant correlation with the infection (P = 0.006, OR = 4.33). Based on our phylogenetic study, the HTLV-1 prevalent sequence type of Torbat-e Heydarieh belongs to the cosmopolitan subtype A. HTLV-1 prevalence in Torbat-e Heydarieh (1.25%) is low comparing to those of both Mashhad (2-3%) and Neishabour (3.5-5%) in the province of Khorasan. Thus, traveling mobility and population mixing such as marriage, bureaucratic affairs, occupation, and economic activities could be the usual routs of HTLV-1 new wave of spreading in this segregated city.
Subject(s)
Ethnicity , HTLV-I Infections/ethnology , HTLV-I Infections/virology , Human T-lymphotropic virus 1/classification , Human T-lymphotropic virus 1/genetics , Adolescent , Adult , Age Factors , Aged , Child , Child, Preschool , Female , HIV Long Terminal Repeat , HTLV-I Infections/immunology , Human T-lymphotropic virus 1/immunology , Humans , Infant , Infant, Newborn , Iran/epidemiology , Lymphocytes/virology , Male , Middle Aged , Phylogeny , Prevalence , Proviruses/immunology , Proviruses/isolation & purification , Risk Factors , Sequence Analysis, DNA , Socioeconomic Factors , Young AdultABSTRACT
Desde a década de 90 o Instituto Adolfo Lutz de São Paulo (IAL) tem realizado o diagnóstico da infecção por Vírus Linfotrópicos de Células T Humanas dos tipos 1 e 2 (HTLV-1 e HTLV-2) e, desde então, têm sido reportadas as dificuldades principalmente no diagnóstico de HTLV-2, em especial em pacientes infectados pelo HIV-1. O presente trabalho teve como objetivo avaliar várias técnicas de diagnóstico disponíveis no momento atual (kits comerciais e testes in house) e estabelecer o melhor algoritmo para ser empregado no diagnóstico de pacientes infectados pelo HIV-1. A população analisada foi composta por dois grupos provenientes de Serviços de Assistência Especializados em HIV/AIDS de São Paulo: um pioneiro [Grupo 1 (G1), n=1.608] e outro com histórico mais recente [Grupo 2 (G2), n=1.383]. Ambos os grupos foram formados, na maioria, por indivíduos do sexo masculino... (AU).
Since the 90 decade, the Instituto Adolfo Lutz (IAL) has performed the diagnosis of Human T-cell Lymphotropic Virus type 1 and type 2 (HTLV-1 and HTLV-2), and thenceforth the difficulties in diagnosing HTLV-2 have been reported, mostly in HIV-infected patients. The present study aimed at evaluating the several diagnostic techniques currently available (commercial kits and in-house assays), and to establish the best algorithm to be employed for diagnosing HTLV-1/-2 in patients infected with HIV-1. The study population was composed by two patient groups attended at HIV/AIDS specialized services care in São Paulo: the pioneer one [Group 1 (G1), n=1,608], and the other with the most recent historical health setting [Group 2 (G2), n=1,383. The majority of the both groups were composed by male patients...(AU).
Subject(s)
Humans , Male , Female , HIV-1 , Algorithms , Clinical Laboratory Techniques/methods , Coinfection/complications , Coinfection/diagnosis , HIV Infections , HTLV-I Infections , HTLV-II Infections , Human T-lymphotropic virus 1ABSTRACT
O Brasil é considerado o país com o maior número absoluto de indivíduos infectados pelos vírus linfotrópicos de células T humanas dos tipos 1 e 2 (HTLV-1 e HTLV2), perto de 2,5 milhões; além disso, é também considerado epidêmico para o HIV e, portanto, casos de coinfecção HIV/HTLV são frequentes no país. O presente trabalho efetuou o seqüenciamento das regiões LTR, env e tax do genoma proviral do HTLV-1 e do HTLV-2 isolados das amostras de sangue de pacientes coinfectados pelo HIV-1 de Londrina e região (n=34) e de São Paulo (n=20), para realizar a caracterização molecular e determinar subtipos virais. Foram utilizadas na análise das sequências as ferramentas Sequencher 4.7, BLAST, Genotyping-NCBI, Subtyping-REGA, BioEdit 7.0.5.3, ClustalW, GenBank, PAUP 4.0.b10, Modeltest 3.7, TreeView 1.6.6 e MEGA4. As diversas análises confirmaram como subtipos prevalentes o HTLV-1a, subgrupo Transcontinental A, e o HTLV-2a (variante -2c). Foram detectadas assinaturas moleculares nos isolados do Brasil. Detectou-se o genótipo brasileiro taxA para o HTLV-1 e para o HTLV-2 a Tax longa, a qual é característica da variante HTLV-2c. Houve também a confirmação da troca de aminoácido S1909P no env dos HTLV-2. Especulou-se sobre duas entradas do HTLV-1 no Brasil e sobre a disseminação do HTLV-2c em grupos distintos quanto ao comportamento de risco e região geográfica. O estabelecimento de métodos laboratoriais otimizados para isolados brasileiros de HTLV-1 e HTLV-2 possibilitou melhor compreensão da diversidade genômica e da origem e disseminação dos HTLVs em populações coinfectadas pelo HIV no Brasil
Brazil is considered the country with the major absolute number of individuals infected with human T-lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2), close to 2,500,000; moreover, it is also considered epidemic for HIV/Aids =and therefore HIV/HTLV coinfection is frequent in the country. This study aimed at sequencing the LTR, env and tax regions of the proviral genome of HTLV-1 and HTLV-2 isolated from blood samples obtained from patients coinfected with HIV-1 from Londrina and vicinities (n=34) and São Paulo (n=20), in order to perform the molecular characterization and viral subtyping. For sequences analysis, several bioinformatics tools were employed: Sequencher 4.7, BLAST, Genotyping-NCBI, Subtyping-REGA, BioEdit 7.0.5.3, ClustalW, GenBank, PAUP 4.0.b10, Modeltest 3.7, TreeView 1.6.6 and MEGA4. The results confirmed as prevalent the HTLV-1a subtype, the Transcontinental subgroup A, and the HTLV-2a (variant-2c). Molecular signatures characteristic of Brazilian isolates were detected: taxA Brazilian genotype in HTLV-1, and the long Tax which is characteristic of the HTLV-2c in HTLV-2. Also, it was confirmed the S1909P amino acid change in the env region of HTLV-2c. It was speculated on two entrances of HTLV-1 in Brazil, and on the spread of HTLV-2c in distinct groups related to risk factors and geographic region. The establishment and optimization of laboratory methods performed in this study allowed to get a better understanding on HTLVs genomic diversity, and to give insights on the origin and spread of HTLVs in populations coinfected with HIV in Brazil
Subject(s)
Humans , Male , Female , Patients/classification , Human T-lymphotropic virus 1/pathogenicity , Human T-lymphotropic virus 2/pathogenicity , Acquired Immunodeficiency Syndrome/pathology , HIV/pathogenicity , Genome , Phylogeny , Retroviridae , Virology , Brazil , Blood Specimen Collection/methods , Epidemiology , MicrobiologyABSTRACT
O Brasil é o país com o maior número de pessoas infectadas pelos vírus linfotrópicos de células T humanas dos tipos 1e -2 (HTLV-1 e HTLV2) com mais de 2,5 milhões de indivíduos infectados. Em 1993, a realização de testes sorológicos específicos tornou-se obrigatória em Bancos de Sangue. O HTLV-1 causa leucemia/linfoma de células T do adulto e mielopatia associada ao HTLV-1/paraparesia espástica tropical além de outras doenças, enquanto o HTLV-2 pode causar alguns quadros neurológicos e alterar a evolução de HIV/Aids. Os testes sorológicos que identificam anticorpos específicos disponíveis no mercado têm falhado no diagnóstico, principalmente de infecção por HTLV-2. Vários algoritmos de testes de triagem e confirmatórios têm sido propostos, mas nenhum deles se mostrou 100% eficiente com casuística de alto risco. Muitos soros resultam em padrão indeterminado no Western blot, e os isolados virais utilizados na composição dos kits podem ser a causa desses resultados. As técnicas de biologia molecular têm sido descritas como testes confirmatórios, mas não têm sido empregadas na rotina. Desde 1991, a Seção de Imunologia do Instituto Adolfo Lutz tem estudado a infecção por HTLV-1/2, contribuindo para o diagnóstico sorológico e molecular, e tem como desafio implantar um teste laboratorial capaz de detectar infecção causada por cepas brasileiras de HTLV-2.
Subject(s)
Clinical Laboratory Techniques , Polymerase Chain Reaction , Serology , Immunoenzyme Techniques , Human T-lymphotropic virus 1 , Blotting, WesternABSTRACT
The current diagnosis of human T-lymphotropic virus type-2 (HTLV-2) infection is based on the search of specific antibodies; nevertheless, several studies conducted in Brazil pointed deficiencies of the commercially available kits in detecting HTLV-2, mostly in HIV/AIDS patients. This study searched for the presence of HTLV-1 and -2 in 758 HIV/AIDS patients from Londrina, Paraná, Brazil. Serum samples were screened for HTLV-1/2 antibodies using two EIA kits (Vironostika and Murex), and confirmed by WB (HTLV Blot 2.4, Genelabs). The results obtained by EIA disclosed 49 (6.5 percent) reactive sera: 43 positive by both EIA kits, and six with discordant results. WB confirmed HTLV-1 infection in seven samples (0.9 percent) and HTLV-2 in 21 sera (2.8 percent). Negative and indeterminate results were detected in four (0.5 percent) and 16 (2.1 percent) sera, respectively. Blood from 47 out of 49 HTLV seroreactive patients were collected and analyzed for the presence of env, LTR and tax genomic segments of HTLVs by PCR. PCR confirmed six cases of HTLV-1 and 37 cases of HTLV-2 infection (14 out of 16 that were found to be WB indeterminate). Restriction analysis of the env PCR products of HTLV-2 disclosed 36 isolates of HTLV-2a/c subtype, and one of HTLV-2b subtype. These results emphasize the need of improving serologic tests for detecting truly HTLV-2 infected patients from Brazil, and confirm the presence of HTLV-2b subtype in the South of this country.
O diagnóstico de infecção por HTLV-2 se baseia na pesquisa de anticorpos específicos, entretanto, vários estudos conduzidos no Brasil têm apontado falhas nos kits sorológicos disponíveis no mercado em detectar HTLV-2, principalmente nos pacientes com HIV/aids. Este trabalho avaliou a presença de infecção por HTLV-1 e -2 em 758 pacientes HIV/aids de Londrina, Paraná, Brasil. Amostras de soro foram analisadas quanto à presença de anticorpos anti-HTLV-1/2 por dois kits de EIA (Vironostika e Murex) e confirmados por WB (HTLV Blot 2.4, Genelabs). Os resultados obtidos pelos testes sorológicos mostraram 49 (6,5 por cento) soros reagentes: 43 positivos para ambos os kits e seis com resultados discordantes. O WB confirmou infecção por HTLV-1 em sete soros (0,9 por cento) e HTLV-2 em 21 soros (2,8 por cento). Resultados negativos e indeterminados foram detectados, respectivamente, em quatro (0,5 por cento) e 16 (2,1 por cento) soros. Amostras de sangue de 47 dos 49 pacientes com sorologia reagente foram avaliadas quanto à presença de segmentos do genoma dos HTLVs (env, LTR e tax), usando a técnica de PCR. As PCRs confirmaram seis casos de infecção por HTLV-1 e 37 casos por HTLV-2 (14 dos 16 cuja sorologia resultou WB indeterminada). A subtipagem de HTLV-2 por análise de restrição enzimática de produtos da PCR env mostrou 36 isolados de subtipo HTLV-2a/c e um HTLV-2b. Esses resultados reforçam a necessidade de melhorar o diagnóstico de infecção por HTLV-2 no Brasil e confirmam a presença do subtipo HTLV-2b na região sul do país.
