RESUMO
HTLV-1 is the virus that causes T cell lymphoma/leukemia in adults and a neurological disorder known as HTLV-associated myelopathy or tropical spastic paraparesis. One of the transmission means is through contaminated blood and its byproducts. Because of the risk of HTLV-associated infections, screening for HTLV was introduced for Brazilian blood donors in 1993. Most of the diagnostic kits used in the national blood banks are bought from foreign companies. Brazil does not have the technology to produce this material and there is a need to produce diagnostic systems with national technology. In this study, we show the expression of gp21/HTLV-1 in Escherichia coli and its reactivity towards monoclonal antibodies and the antibodies of infected patients. Expressing these proteins is the first step towards obtaining diagnostic kits with Brazilian biotechnology.
Assuntos
Clonagem Molecular , Produtos do Gene env/química , Vírus Linfotrópico T Tipo 1 Humano/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Vetores Genéticos , Anticorpos Anti-HTLV-I/genética , Anticorpos Anti-HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Immunoblotting , Reação em Cadeia da Polimerase , Produtos do Gene env do Vírus da Imunodeficiência Humana/isolamento & purificaçãoRESUMO
O HTLV-1 é o vírus causador da leucemia/linfoma de célula T no adulto e de uma desordem neurológica conhecida por mielopatia associada ao HTLV ou paraparesia espástica tropical. Um dos modos de transmissão é pelo sangue contaminado e seus subprodutos e, devido ao risco de infecções associadas ao HTLV sua pesquisa na triagem de doadores de sangue foi introduzida no Brasil a partir de 1993. Os kits diagnósticos utilizados nos bancos de sangue nacionais são na sua maioria comprados de empresas estrangeiras. O Brasil não detém a tecnologia para produção deste material e há a necessidade de produção de sistemas de diagnóstico com tecnologia nacional. Neste trabalho, mostramos a expressão da gp21/HTLV-1 em Escherichia coli e sua reatividade frente a anticorpos monoclonais e de pacientes infectados. Expressar tais proteínas é o primeiro passo para obtenção de conjuntos diagnósticos com tecnologia brasileira.
HTLV-1 is the virus that causes T cell lymphoma/leukemia in adults and a neurological disorder known as HTLV-associated myelopathy or tropical spastic paraparesis. One of the transmission means is through contaminated blood and its byproducts. Because of the risk of HTLV-associated infections, screening for HTLV was introduced for Brazilian blood donors in 1993. Most of the diagnostic kits used in the national blood banks are bought from foreign companies. Brazil does not have the technology to produce this material and there is a need to produce diagnostic systems with national technology. In this study, we show the expression of gp21/HTLV-1 in Escherichia coli and its reactivity towards monoclonal antibodies and the antibodies of infected patients. Expressing these proteins is the first step towards obtaining diagnostic kits with Brazilian biotechnology.
Assuntos
Humanos , Clonagem Molecular , Produtos do Gene env/química , Vírus Linfotrópico T Tipo 1 Humano/química , Proteínas Oncogênicas de Retroviridae/genética , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Anticorpos Anti-HTLV-I/genética , Anticorpos Anti-HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Immunoblotting , Reação em Cadeia da Polimerase , Proteínas Oncogênicas de Retroviridae/isolamento & purificaçãoRESUMO
Nine patients with Kaposi's sarcoma and five suffering from T-cell lymphoma have been examined. Antibodies to HTLV-1 were not found in these patients. The primary cellular cultures were isolated from blood and lymph nodes of the patients. Viral particles (type C) were found in the culture obtained from the patient with lymphoma of T-cell origin. DNAs from the primary cellular cultures from patients with lymphoma or sarcoma contained the sequences homologous to gag-gene of HTLV-1. The data suppose the patients with T-cell lymphoma and Kaposi's sarcoma to carry HTLV-1 virus.
Assuntos
Anticorpos Anti-HTLV-I/análise , Leucemia de Células T/virologia , Sarcoma de Kaposi/virologia , Adulto , Idoso , Células Cultivadas , Feminino , Genes gag , Anticorpos Anti-HTLV-I/genética , Anticorpos Anti-HTLV-I/isolamento & purificação , Humanos , Linfonodos/ultraestrutura , Linfonodos/virologia , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Reação em Cadeia da PolimeraseRESUMO
Epidemiological data indicate that breast feeding is the primary route of mother-to-child transmission of HTLV-I. However, serological studies show that 60 to 90% of infants who are fed breast milk from HTLV-I carriers avoid HTLV-I infection. To understand the mechanism of the virus transmission, the titer of HTLV-I antibodies and p40tax antibody and the copy number of the HTLV-I proviral DNA in peripheral lymphocytes in the HTLV-I carrier-mothers were surveyed. The seroprevalence of HTLV-I in the children born to carrier mothers was 6.1% in a normal breast feeding group, 7.7% in a group fed with freeze-thawed breast milk and none in a bottle-fed group. The difference between the seroconversion rate for the normal breast feeding group and others was statistically insignificant. Our studies also indicated that neither the titer of HTLV-I antibodies in carriers nor the duration of breast feeding was relevant to seroconversion in the children. The seroconversion rate in children was higher in p40tax antibody-positive mothers than in a seronegative group, but the difference was statistically insignificant. In conclusion, the copy number of the HTLV-I provirus in the lymphocytes of the carrier mothers was the most relevant factor in the seroconversion of infants who received breast milk from HTLV-I carriers.
Assuntos
Portador Sadio/transmissão , Anticorpos Anti-HTLV-I/análise , Infecções por HTLV-I/transmissão , Complicações Infecciosas na Gravidez , Sequência de Bases , Aleitamento Materno , Feminino , Produtos do Gene tax/genética , Anticorpos Anti-HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Recém-Nascido , Troca Materno-Fetal , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , GravidezRESUMO
The first of case of adult T-cell prolymphocytic lymphosarcoma is reported which according to the natural course, cell composition of tumor, cell surface markers as well as expressed immune response to a wide spectrum of HTLV-1 gag an env encoded proteins can be classified as HTLV-associated adult T-cell leukemia. Diagnosis of the tumor alongside with identification of HTLV-1-infected individuals in the USSR emphasizes the need to stimulate research in HTLV-1-associated carcinogenesis in this country.
Assuntos
Anticorpos Anti-HTLV-I/análise , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto/epidemiologia , Regulação Viral da Expressão Gênica , Produtos do Gene gag/análise , Anticorpos Anti-HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Immunoblotting , Leucemia-Linfoma de Células T do Adulto/imunologia , Masculino , Pessoa de Meia-Idade , U.R.S.S./epidemiologiaRESUMO
Serum specimens from Puerto Rican residents were tested for antibodies to human T lymphotropic virus type I (HTLV-I) using an enzyme immunoassay, Western immunoblot, and radioimmunoprecipitation assays. Of 1,279 specimens obtained during a dengue virus surveillance program in 1986 and 1987, 3 (0.2%) tested positive; an additional 11 were indeterminate. Of 602 specimens obtained from blood donors in Ponce in 1987, 1 (0.2%) was positive; an additional specimen was indeterminate. Of 21 persons hospitalized for problems related to intravenous drug use in 1986 and 1987, 1 (5%) tested positive for HTLV-I antibodies.
