RESUMO
Adult T cell leukemia/lymphoma is a malignancy with a poor prognosis caused by human T lymphocyte virus type 1 (HTLV-1) infection. Tax and HBZ are two major viral proteins that may be involved in oncogenesis by disrupting apoptosis. Because Bcl-xL plays an integral role in the anti-apoptotic pathway, this study examines the interaction between host apoptosis and oncoproteins. We investigated 37 HTLV-1-infected individuals, including 18 asymptomatic and 19 adult T cell leukemia/lymphoma (ATLL) subjects. mRNA was extracted and converted to cDNA from peripheral blood mononuclear cells, and then gene expression was determined using TaqMan q-PCR. Moreover, the HTLV-1 proviral load (PVL) was also measured using a commercial absolute quantification kit (Novin Gene, Iran). Data analysis revealed that the mean of TAX, HBZ, and PVL was significantly higher among the study groups (ATLL and carrier groups p = .003, p = .000, and p = .002 respectively). There was no statistical difference in Bcl-xL gene expression between the study groups (p = .323). It is proposed that this anti-apoptotic pathway may not be directly involved in the development of ATLL lymphoma. Bcl-xL, TAX, HBZ gene expression, and PVL can be utilized as prognostic markers.
Assuntos
Infecções por HIV , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Linfoma , Adulto , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Leucócitos Mononucleares , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas dos Retroviridae/genética , Proteínas dos Retroviridae/metabolismo , Infecções por HIV/patologia , Linfoma/patologia , Expressão Gênica , Produtos do Gene tax/genética , Produtos do Gene tax/metabolismoRESUMO
BACKGROUND: Human T-lymphotropic virus 1 (HTLV-1) is associated with the development of several pathologies and chronic infection in humans. The inefficiency of the available treatments and the challenge in developing a protective vaccine highlight the need to produce effective immunotherapeutic tools. The HTLV-1 basic leucine zipper (bZIP) factor (HBZ) plays an important role in the HTLV-1 persistence, conferring a survival advantage to infected cells by reducing the HTLV-1 proteins expression, allowing infected cells to evade immune surveillance, and enhancing cell proliferation leading to increased proviral load. METHODS: We have generated a recombinant Modified Virus Vaccinia Ankara (MVA-HBZ) and a plasmid DNA (pcDNA3.1(+)-HBZ) expressing a multiepitope protein based on peptides of HBZ to study the immunogenic potential of this viral-derived protein in BALB/c mice model. Mice were immunized in a prime-boost heterologous protocol and their splenocytes (T CD4+ and T CD8+) were immunophenotyped by flow cytometry and the humoral response was evaluated by ELISA using HBZ protein produced in prokaryotic vector as antigen. RESULTS: T CD4+ and T CD8+ lymphocytes cells stimulated by HBZ-peptides (HBZ42-50 and HBZ157-176) showed polyfunctional double positive responses for TNF-α/IFN-γ, and TNF-α/IL-2. Moreover, T CD8+ cells presented a tendency in the activation of effector memory cells producing granzyme B (CD44+High/CD62L-Low), and the activation of Cytotoxic T Lymphocytes (CTLs) and cytotoxic responses in immunized mice were inferred through the production of granzyme B by effector memory T cells and the expression of CD107a by CD8+ T cells. The overall data is consistent with a directive and effector recall response, which may be able to operate actively in the elimination of HTLV-1-infected cells and, consequently, in the reduction of the proviral load. Sera from immunized mice, differently from those of control animals, showed IgG-anti-HBZ production by ELISA. CONCLUSIONS: Our results highlight the potential of the HBZ multiepitope protein expressed from plasmid DNA and a poxviral vector as candidates for therapeutic vaccine.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Vacinas de DNA , Camundongos , Humanos , Animais , Linfócitos T CD8-Positivos , Granzimas/genética , Fator de Necrose Tumoral alfa , Vacinas de DNA/genética , Proteínas Virais/metabolismo , Vaccinia virus/genética , DNA , Fatores de Transcrição de Zíper de Leucina Básica , Proteínas dos Retroviridae/genéticaAssuntos
Bioensaio/métodos , Retrovirus Endógenos/fisiologia , Xenoenxertos/virologia , Especificidade de Hospedeiro , RNA Mensageiro/análise , RNA Viral/análise , Infecções por Retroviridae/transmissão , Suínos/virologia , Tropismo Viral , Animais , Bioensaio/economia , Sistemas CRISPR-Cas , Retrovirus Endógenos/genética , Genoma Viral , Células HEK293/virologia , Humanos , Splicing de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Viral/biossíntese , RNA Viral/genética , Infecções por Retroviridae/prevenção & controle , Proteínas dos Retroviridae/genética , Proteínas dos Retroviridae/fisiologia , Risco , Replicação ViralRESUMO
The most variable proteins, the gp120's, of the many isolates of HIV-I can be readily compared by two-dimensional oligopeptide maps. The gp120 in a given cell line is completely stable, but the cell line defines the actual gp120 size and may induce minor peptide changes. HTLV-IIIB and LAV differ slightly from each other even when grown in the same cell line, while LAV grown in a B cell line is less related. Molecularly distant isolates have unique patterns. While anti-HTLV-IIIB gp120 antibody neutralized both HTLV-IIIB and LAV, it recognizes only the homologous HTLV-IIIB infected cells in cytotoxicity assays. Structural analysis of isolates should be helpful in defining the range of immunological reactivities among variants as a contribution to a rational approach to a vaccine against AIDS.