Mapping variants in HTLV-1 genome to analyze their impacts on the HAM/TSP development: A systematic review.

The reasons that lead some individuals living with the Human T Lymphotropic Virus 1 (HTLV-1) to develop HAM/TSP are still unclear. To better understand the viral genetic factors that may be associated with the development of HAM/TSP, this study aims to evaluate the impact of HTLV-1 genome mutations on the development of this disease through a systematic review. This review followed the PRISMA guidelines and was registered in the PROSPERO database. The search for articles was performed in PMC, PubMed, Lilacs, SciELO, and Embase databases using the following search descriptors: HTLV-1, HAM/TSP, mutation, polymorphism, genetic variation, and sequenc*. From the 1,929 articles found in the search, 20 were selected according to the pre-defined inclusion and exclusion criteria. A total of 619 HAM/TSP cases were compared with 555 AC controls. The mutations possibly related to the disease progression were detected in hbz (R119Q), tax (A7959V), ORF-I (R88K, P86S, S69G, P45L, L40F, C39R, CR9Y), and gp46 (V247I, N93D, S72G) genetic regions. The data collected and analyzed here indicate that mutations in the HTLV-1 genome could play an important role in the chronic inflammatory state and may be related to the development of HAM/TSP.

Advances in preventive vaccine development against HTLV-1 infection: A systematic review of the last 35 years.

Introduction: The Human T-lymphotropic virus type 1 (HTLV-1) was the first described human retrovirus. It is currently estimated that around 5 to 10 million people worldwide are infected with this virus. Despite its high prevalence, there is still no preventive vaccine against the HTLV-1 infection. It is known that vaccine development and large-scale immunization play an important role in global public health. To understand the advances in this field we performed a systematic review regarding the current progress in the development of a preventive vaccine against the HTLV-1 infection. Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA®) guidelines and was registered at the International Prospective Register of Systematic Reviews (PROSPERO). The search for articles was performed in PubMed, Lilacs, Embase and SciELO databases. From the 2,485 articles identified, 25 were selected according to the inclusion and exclusion criteria. Results: The analysis of these articles indicated that potential vaccine designs in development are available, although there is still a paucity of studies in the human clinical trial phase. Discussion: Although HTLV-1 was discovered almost 40 years ago, it remains a great challenge and a worldwide neglected threat. The scarcity of funding contributes decisively to the inconclusiveness of the vaccine development. The data summarized here intends to highlight the necessity to improve the current knowledge of this neglected retrovirus, encouraging for more studies on vaccine development aiming the to eliminate this human threat. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier (CRD42021270412).

Silencioso e negligenciado: o que se sabe após quatro décadas do descobrimento do HTLV-1? / Silent and neglected: what is known after four decades of the discovery of the HTLV-1? / Silencioso y descuidado: ¿qué se sabe después de cuatro décadas del descubrimiento del HTLV-1?

O vírus linfotrópico T humano tipo 1 (HTLV-1) foi o primeiro retrovírus humano descoberto, descrito pela primeira vez há 41 anos. Esse retrovírus está associado ao desenvolvimento de duas doenças graves: a leucemia/linfoma de células T do adulto (ATLL) e a mielopatia associada ao HTLV-1/paraparesia espástica tropical (HAM/TSP). Este trabalho teve como objetivo analisar as atualizações sobre o HTLV-1, destacando os aspectos clínicos, os avanços e as limitações no tratamento e na prevenção da infecção pelo HTLV-1. Para isso, foi realizada uma revisão integrativa, por meio de coleta de dados nas plataformas PubMed, LILACS e SciELO, entre março e abril de 2021. Foram incluídos 61 artigos de diferentes países. O Brasil foi o país com maior número de publicações na área: 12. Os resultados obtidos mostram que existem avanços importantes no que diz respeito ao tratamento e à prevenção da infecção pelo HTLV-1. No entanto, a falta de estudos específicos sobre o vírus, que abordem os aspectos clínicos da infecção, foi um fator limitante para este estudo, o que reforça a necessidade de investimento em novas pesquisas sobre o tema.

The Human T-lymphotropic Virus 1 (HTLV-1) was the first human retrovirus discovered, described for the first time 41 years ago. This retrovirus is associated with the development of two serious diseases: adult T-cell leukemia/lymphoma (ATLL) and tropical spastic paraparesis/HTLV-1-associated myelopathy (HAM/TSP). This study aimed to analyze the updates about HTLV-1, highlighting the clinical aspects, advances, and limitations in the treatment and prevention of HTVL-1 infection. To this end, an integrative review was carried out, with data collection on PubMed, LILACS, and SciELO platforms, between March and April 2021. A total of 61 articles from different countries were included. Brazil was the country with the largest number of publications in the area: 12. The results showed effective advances regarding treating and preventing HTLV-1 infection. However, the lack of specific studies about the virus, which address the clinical aspects of the infection, was a limiting factor for this study, which reinforces the need for investment in new research about this topic.

El virus linfotrópico T tipo 1 humano (HTLV-1) fue el primer retrovirus humano descubierto y se describió por primera vez hace 41 años. Este retrovirus está asociado con el desarrollo de dos enfermedades graves: leucemia/linfoma de células T del adulto (ATLL) e mielopatía asociada a HTLV-1/paraparesia espástica tropical (HAM/TSP). Este estudio tuvo como objetivo analizar las actualizaciones sobre HTLV-1, destacando los aspectos clínicos, los avances y limitaciones en el tratamiento y prevención de la infección por HTLV-1. Para ello, se realizó una revisión integradora, a través de la recolección de datos en las plataformas PubMed, LILACS y SciELO entre marzo y abril de 2021. Se incluyeron 61 artículos de diferentes países. Brasil fue el país con mayor número de publicaciones en el área: 12. Los resultados obtenidos muestran que existen avances efectivos en cuanto al tratamiento y prevención de la infección por HTLV-1. Sin embargo, la falta de estudios específicos sobre el virus que aborden los aspectos clínicos de la infección fue un factor limitante para el presente estudio, lo que refuerza la necesidad de invertir en nuevas investigaciones sobre este virus.