Epidemiological and clinical profile of HTLV-1 patients: a closer look at a reference center in Bahia, Brazil.

The human T-lymphotropic virus type 1 (HTLV-1) affects over 5 million people worldwide and is endemic in Brazil. Though HTLV-1 is a notifiable disease, the last epidemiological report regarding HTLV-1 infection covered the period from 2012 to 2019. To understand the specific challenges and to develop the best strategies for controlling HTLV-1 infection, it is important to know the characteristics of each region providing care to people living with this virus. This descriptive cross-sectional study evaluated patients treated at the HTLV reference center in Vitória da Conquista, Bahia, Brazil, between July 2021 and August 2022. The data were obtained through the analysis of medical records and routine clinical consultations. A total of 67 patients were evaluated, with 79.1% being female, 79.1% identifying as black, indigenous, and people of color, 37.31% being married, 80.6% identifying as heterosexual, and 59.7% reporting inconsistent condom use. Additionally, 37.3% of the patients were diagnosed with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic disease with a considerable effect on the quality of life. Furthermore, 53.7% of the patients had incomplete/complete elementary education, and 52.2% had an income of up to one minimum wage. The data highlight the necessity for more specific public policies (such as health education strategies, aimed at reducing the number of new infections) targeting the described at-risk population.

Genomic Detection of the Emerging, Highly Pathogenic HIV-1 Subtype D in Bahia, Northeast Brazil.

(1) Background: The HIV subtype D is generally associated with a faster decline in CD4+ T cell counts, a higher viral load, and a faster progression to AIDS. However, it is still poorly characterized in Brazil. In this study, we used genomics and epidemiological data to investigate the transmission dynamics of HIV subtype D in the state of Bahia, Northeast Brazil. (2) Methods: To achieve this goal, we obtained four novel HIV-1 subtype D partial pol genome sequences using the Sanger method. To understand the emergence of this novel subtype in the state of Bahia, we used phylodynamic analysis on a dataset comprising 3704 pol genome sequences downloaded from the Los Alamos database. (3) Results: Our analysis revealed three branching patterns, indicating multiple introductions of the HIV-1 subtype D in Brazil from the late 1980s to the late 2000s and a single introduction event in the state of Bahia. Our data further suggest that these introductions most likely originated from European, Eastern African, Western African, and Southern African countries. (4) Conclusion: Understanding the distribution of HIV-1 viral strains and their temporal dynamics is crucial for monitoring the real-time evolution of circulating subtypes and recombinant forms, as well as for designing novel diagnostic and vaccination strategies. We advocate for a shift to active surveillance, to ensure adequate preparedness for future epidemics mediated by emerging viral strains.

The effect of reactor scale on biochars and pyrolysis liquids from slow pyrolysis of coffee silverskin, grape pomace and olive mill waste, in auger reactors.

Several studies have addressed the potential biorefinery, through small-scale pyrolysis, of coffee silverskin (CSS), grape pomace (GP) and olive mill waste (OMW), which are respectively the main solid residues from coffee roasting, wine making and olive oil production processes. However, increasing the scale of reactor to bring these studies to an industrial level may affect the properties, and hence applications, of the resulting products. The aim of this study is therefore to perform pilot scale experiments to compare and verify the results of analytical study (TGA) and bench scale reactor runs, in order to understand the fundamental differences and create correlations between pyrolysis runs at different scales. To this end, pyrolysis liquids and biochars from the slow pyrolysis of CSS, GP and OMW, performed using different scale auger reactors (15 kg/h and 0.3 kg/h), have been analysed (TGA, pH, density, proximate and ultimate analyses, HHV, FTIR, GCMS) and compared. The results showed no major differences in biochars when the temperature and the solid residence time were fixed. However, regarding pyrolysis liquids, compounds from the lab reactor were more degraded than pilot plant ones, due to, in this case, the vapour residence time was longer. Regarding the properties of the pyrolysis products, GP 400 °C biochars showed the best properties for combustion; CSS biochars were especially rich in nitrogen, and 400 °C GP and OMW pyrolysis liquids showed the highest number of phenolics. Hence, this study is considered a first step towards industrial scale CSS, GP and OMW pyrolysis-based biorefinery.

An overview of sequencing technology platforms applied to HTLV-1 studies: a systematic review.

Human T-lymphotropic virus type 1 (HTLV-1) was the first human retrovirus described. The viral factors involved in the different clinical manifestations of infected individuals are still unknown, and in this sense, sequencing technologies can support viral genome studies, contributing to a better understanding of infection outcome. Currently, several sequencing technologies are available with different approaches. To understand the methodological advances in the HTLV-1 field, it is necessary to organize a synthesis by a rigorous review. This systematic literature review describes different technologies used to generate HTLV-1 sequences. The review follows the PRISMA guidelines, and the search for articles was performed in PubMed, Lilacs, Embase, and SciELO databases. From the 574 articles found in search, 62 were selected. The articles showed that, even with the emergence of new sequencing technologies, the traditional Sanger method continues to be the most commonly used methodology for generating HTLV-1 genome sequences. There are many questions that remain unanswered in the field of HTLV-1 research, and this reflects on the small number of studies using next-generation sequencing technologies, which could help address these gaps. The data compiled and analyzed here can help research on HTLV-1, assisting in the choice of sequencing technologies.

Dynamic Dispersion of HIV-1 Subtype C Toward Brazilian Northeastern Region.

The subtype C accounts for >50% of HIV type 1 (HIV-1) infections worldwide and it is currently the predominant viral form in South Brazil. Subtype C has been reported in all Brazilian regions; however, the phylogenetic relationship among strains circulating in those regions still remains unclear. This study aimed to investigate the origin and dynamic dispersion of HIV-1 subtype C toward Northeast Brazil. Our phylogenetic analysis suggests that most subtype C strains circulating in Brazil (99%) are descendant from the main lineage whose entrance in the country was previously described in the 1970s. According to the literature, additional introductions of subtype C were reported in the country through the Southeast region and in this study we identified another entry event that occurred most likely through the North region. Furthermore, our analysis suggests that the spread of subtype C to Brazilian Northeastern states occurred through multiple independent introductions of the main lineage that originated in South Brazil between mid-1980s and late 1990s. Despite the observation of eventual new HIV-1 subtype C introductions, our results highlight the predominance of a single lineage of this subtype in Brazil and the importance of South region in its dissemination throughout the country.

Molecular characterization of HTLV-1 genomic region hbz from patients with different clinical conditions.

The human T-cell lymphotropic virus type-1 (HTLV-1) is associated with severe pathologies, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), adult T-cell leukemia-lymphoma (ATLL), and infective dermatitis associated with the HTLV-1 (IDH). Interestingly, HTLV-1 infection does not necessarily imply the development of pathological processes and it is unknown why some patients remain asymptomatic carriers (AC). Despite some mutations in the HTLV-1 genome appear to influence the outcome of HTLV-1, there are few studies that characterize molecularly the hbz region. This study aimed to perform the molecular characterization of hbz gene isolated from patients with different clinical outcomes. A total of 15 sequences were generated and analyzed with 571 sequences previously published. The analises showed that the R119Q mutation seems to be related to HTLV-1 clinical conditions since the frequency of this HBZ mutation is significantly different in comparison between AC with HAM/TSP and ATLL. The R119Q mutation is possibly a protective factor as the frequency is higher in AC sequences.

Chemical stabilization of Cd-contaminated soil using fresh and aged wheat straw biochar.

Metal mining and smelting activities can introduce a substantial amount of potentially toxic elements (PTE) into the environment that can persist for an extended period. That can limit the productivity of the land and creates dangerous effects on ecosystem services. The effectiveness of wheat straw biochar to immobilize Cd in contaminated soil due to metal smelting activities was investigated in this study. The biochar carbon stability and long-term provisioning of services depend on the biochar production conditions, nature of the feedstock, and the biotic and abiotic environmental conditions in which the biochar is being used. Within this context, three types of wheat straw biochar were produced using a screw reactor at 400 °C, 500 °C, and 600 °C and tested in a laboratory incubation study. Soil was amended with 2 wt% of biochar. Both fresh and aged forms of biochar were used. Biochars produced at lower temperatures were characterized by lower pH, a lower amount of stable C, and higher amounts of acidic surface functional groups than the freshly produced biochars at higher production temperatures. At the end of the 6 months of incubation time, compared to the soil only treatment, fresh and aged forms of wheat straw biochar produced at 600 °C reduced the Cd concentration in soil pore water by 22% and 15%, respectively. Our results showed that the aged forms of biochar produced at higher production temperatures (500 °C and 600 °C) immobilized Cd more efficiently than the aged forms of lower temperature biochar (400 °C). The findings of this study provide insights to choose the production parameters in wheat straw biochar production while considering their aging effect to achieve successful stabilization of Cd in contaminated soils.

Complete genome sequence of human T-cell lymphotropic type 1 from patients with different clinical profiles, including infective dermatitis.

The HTLV-1 is the first human retrovirus and is associated with several clinical syndromes, however, the pathogenesis of these clinical manifestations is still not fully understood. Furthermore, there are few complete genomes publicly available, about 0.12 complete genomes per 10,000 infected individuals and the databases have a major deficiency of sequences information. This study generated and characterized 31 HTLV-1 complete genomes sequences derived from individuals with Tropical Spastic Paraparesis/HTLV-1-Associated Myelopathy (TSP/HAM), Adult T-cell leukemia/lymphoma (ATL), infective dermatitis associated to HTLV-1 (IDH) and asymptomatic patients. These sequences are associated to clinical and epidemiological information about the patients. The sequencing data generated on Ion Torrent PGM platform were assembled and mapped against the reference HTLV-1 genome. These sequences were genotyped as Cosmopolitan subtype, Transcontinental subgroup. We identified the variants in the coding regions of the genome of the different clinical profiles, however, no statistical relation was detected. This study contributed to increase of HTLV-1 complete genomes in the world. Furthermore, to better investigate the contribution of HTLV-1 mutations for the disease outcome it is necessary to evaluate the interaction of the viral genome and characteristics of the human host.

Molecular Epidemiology Database for Sequence Management and Data Mining.

A central database to aggregate sequence information from a range of epidemiological aspects including HTLV-1 pathogenesis, origin, and evolutionary dynamic would be useful to scientists and physicians worldwide. This Chapter describes two online tools for studies related to HTLV-1, the HTLV-1 Molecular Epidemiology Database and the HTLV-1 Subtyping Tool. The HTLV-1 Molecular Epidemiology Database is a tool for sequence management and data mining which allows researchers to download sequences with clinical and demographic information. The HTLV-1 Subtyping Tool is an online software used for HTLV-1 genotyping, the algorithm consists in the alignment of a query sequence with a carefully selected set of predefined reference strains, followed by phylogenetic analysis.

CD4+ T-cell Count may not be a Useful Strategy to Monitor Antiretroviral Therapy Response in HTLV-1/HIV Co-infected Patients.

BACKGROUND: HTLV-1/HIV co-infection is known to elevate the CD4+ T-cell counts of treatment-naïve persons. We investigated whether HTLV-1/HIV co-infected patients continued to have elevated CD4+ T-cell counts after developing virologic failure on antiretroviral therapy (ART). METHODS: The data is taken from a drug resistance study located in the KwaZulu-Natal province of South Africa. All participants (N=383) presented for repeated CD4+ T-cell count and HIV viral load level testing between January 2006 and March 2014. We used a random-coefficient model to estimate the change in CD4+ T-cell count and HIV viral load level by HTLV-1/HIV co-infection status over time, adjusting for age, sex, and duration of virologic failure. RESULTS: HTLV-1/HIV co-infected participants (n=8) had higher CD4+ T-cell counts, with a positive difference of 117.2 cells/µL at the ART initiation date (p-value=0.001), 114.7 cells/µL (pvalue< 0.001) 12 months after this date, and 112.3 cells/µL (p-value=0.005) 24 months after this date, holding all else constant. In contrast, there was no difference in the HIV viral load level by HTLV-1/HIV co-infected status throughout the observation period. CONCLUSION: We show that HTLV-1/HIV co-infected participants continued to have elevated CD4+ T-cell counts after developing virologic failure on ART, despite no difference in their HIV viral load levels when compared with HIV mono-infected participants. Our results indicate that CD4+ T-cell count testing may not be a useful strategy to monitor ART response in the presence of HTLV-1/HIV co-infection.

HTLV-1aA introduction into Brazil and its association with the trans-Atlantic slave trade.

INTRODUCTION: Human T-lymphotropic virus (HTLV) is an endemic virus in some parts of the world, with Africa being home to most of the viral genetic diversity. In Brazil, HTLV-1 is endemic amongst Japanese and African immigrant populations. Multiple introductions of the virus in Brazil from other epidemic foci were hypothesized. The long terminal repeat (LTR) region of HTLV-1 was used to infer the origin of the virus in Brazil, using phylogenetic analysis. METHODS: LTR sequences were obtained from the HTLV-1 database (http://htlv1db.bahia.fiocruz.br). Sequences were aligned and maximum-likelihood and Bayesian tree topologies were inferred. Brazilian specific clusters were identified and molecular-clock and coalescent models were used to estimate each cluster's time to the most recent common ancestor (tMRCA). RESULTS: Three Brazilian clusters were identified with a posterior probability ranged from 0.61 to 0.99. Molecular clock analysis of these three clusters dated back their respective tMRCAs between the year 1499 and the year 1668. Additional analysis also identified a close association between Brazilian sequences and new sequences from South Africa. CONCLUSION: Our results support the hypothesis of a multiple introductions of HTLV-1 into Brazil, with the majority of introductions occurring in the post-Colombian period. Our results further suggest that HTLV-1 introduction into Brazil was facilitated by the trans-Atlantic slave trade from endemic areas of Africa. The close association between southern African and Brazilian sequences also suggested that greater numbers of the southern African Bantu population might also have been part of the slave trade than previously thought.

Analyses of HTLV-1 sequences suggest interaction between ORF-I mutations and HAM/TSP outcome.

The region known as pX in the 3' end of the human T-cell lymphotropic virus type 1 (HTLV-1) genome contains four overlapping open reading frames (ORF) that encode regulatory proteins. HTLV-1 ORF-I produces the protein p12 and its cleavage product p8. The functions of these proteins have been linked to immune evasion and viral infectivity and persistence. It is known that the HTLV-1 infection does not necessarily imply the development of pathological processes and here we evaluated whether natural mutations in HTLV-1 ORF-I can influence the proviral load and clinical manifestation of HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). For that, we performed molecular characterization, datamining and phylogenetic analysis with HTLV-1 ORF-I sequences from 156 patients with negative or positive diagnosis for HAM/TSP. Our analyses demonstrated that some mutations may be associated with the outcome of HAM/TSP (C39R, L40F, P45L, S69G and R88K) or with proviral load (P34L and F61L). We further examined the presence of mutations in motifs of HBZ and observed that P45L mutation is located within the HBZ nuclear localization signal and was found more frequently between patients with HAM/TSP and high proviral load. These results indicate that some natural mutations are located in functional domains of ORF-I and suggests a potential association between these mutations and the proviral loads and development of HAM/TSP. Therefore it is necessary to conduct functional studies aimed at evaluating the impact of these mutations on the virus persistence and immune evasion.

Deep Sequencing Analysis of Human T Cell Lymphotropic Virus Type 1 Long Terminal Repeat 5' Region from Patients with Tropical Spastic Paraparesis/Human T Cell Lymphotropic Virus Type 1-Associated Myelopathy and Asymptomatic Carriers.

The aim of this study was to analyze patients by deep sequencing the human T cell lymphotropic virus type 1 (HTLV-1) long terminal repeat (LTR) region in order to determine if minor and/or major mutations in this promoter region might be associated with tropical spastic paraparesis (TSP)/human T cell lymphotropic virus type 1-associated myelopathy (HAM) outcome or proviral load or HTLV-1 expression. This study is a cross-sectional analyze of 29 HTLV-1-infected patients with TSP/HAM or asymptomatic carriers. Proviral DNA from those subjects was submitted to a nested PCR for the HTLV-1 LTR5' region. The HTLV-1 LTR5' purified products were submitted to deep sequencing using the Ion Torrent sequencing technology (Life Technologies, Carlsbad, CA). We found that samples with low proviral load showed more detected minor mutations than the samples with high proviral load. Mutations in 136 positions were found over the 520-bp analyzed fragment of HTLV-1 LTR5' with at least 1% frequency. Eleven mutations were present in the previously determined major transcription factor binding sites (TFBS) and in more than one patient, indicating that there might be a differential HTLV-1 expression comparing individuals or in comparing different cells from the same individual. Three mutations were statistically significant using the Fisher nonparametric test between the groups but were not present in previously determined TFBS (G126C/T, G306C, and C479T). Those mutations that were not present in previously determined TFBS were statistically significant in this study and were most frequent in patients with low proviral load or in asymptomatic carriers. Although those mutations were not present in previously determined TFBS, one of those mutations (G306C/A) was present in an Sp-1 binding site determined by in silico analysis, and its presence abrogated the site for Sp-1 binding and created a new possible ATF binding site.

Molecular Characterization of the Human Immunodeficiency Virus Type 1 in Women and Their Vertically Infected Children.

Approximately 35 million people worldwide are infected with human immunodeficiency virus (HIV) around 3.2 million of whom are children under 15 years. Mother-to-child-transmission (MTCT) of HIV-1 accounts for 90% of all infections in children. Despite great advances in the prevention of MTCT in Brazil, children are still becoming infected. Samples from 19 HIV-1-infected families were collected. DNA was extracted and fragments from gag, pol, and env were amplified and sequenced directly. Phylogenetic reconstruction was performed. Drug resistance analyses were performed in pol and env sequences. We found 82.1% of subtype B and 17.9% of BF recombinants. A prevalence of 43.9% drug resistance-associated mutations in pol sequences was identified. Of the drug-naive children 33.3% presented at least one mutation related to protease inhibitor/nucleoside reverse transcriptase inhibitor/nonnucleoside reverse transcriptase inhibitor (PI/NRTI/NNRTI) resistance. The prevalence of transmitted drug resistance mutations was 4.9%. On env we found a low prevalence of HR1 (4.9%) and HR2 (14.6%) mutations.

Genetic characterisation of Langerin gene in human immunodeficiency virus-1-infected women from Bahia, Brazil

Studies on human genetic variations are a useful source of knowledge about human immunodeficiency virus (HIV)-1 infection. The Langerin protein, found at the surface of Langerhans cells, has an important protective role in HIV-1 infection. Differences in Langerin function due to host genetic factors could influence susceptibility to HIV-1 infection. To verify the frequency of mutations in the Langerin gene, 118 samples from HIV-1-infected women and 99 samples from HIV-1-uninfected individuals were selected for sequencing of the promoter and carbohydrate recognition domain (CRD)-encoding regions of the Langerin gene. Langerin promoter analysis revealed two single nucleotide polymorphisms (SNPs) and one mutation in both studied groups, which created new binding sites for certain transcription factors, such as NFAT5, HOXB9.01 and STAT6.01, according to MatInspector software analysis. Three SNPs were observed in the CRD-encoding region in HIV-1-infected and uninfected individuals: p.K313I, c.941C>T and c.983C>T. This study shows that mutations in the Langerin gene are present in the analysed populations at different genotypic and allelic frequencies. Further studies should be conducted to verify the role of these mutations in HIV-1 susceptibility.

Genetic characterisation of Langerin gene in human immunodeficiency virus-1-infected women from Bahia, Brazil.

Studies on human genetic variations are a useful source of knowledge about human immunodeficiency virus (HIV)-1 infection. The Langerin protein, found at the surface of Langerhans cells, has an important protective role in HIV-1 infection. Differences in Langerin function due to host genetic factors could influence susceptibility to HIV-1 infection. To verify the frequency of mutations in the Langerin gene, 118 samples from HIV-1-infected women and 99 samples from HIV-1-uninfected individuals were selected for sequencing of the promoter and carbohydrate recognition domain (CRD)-encoding regions of the Langerin gene. Langerin promoter analysis revealed two single nucleotide polymorphisms (SNPs) and one mutation in both studied groups, which created new binding sites for certain transcription factors, such as NFAT5, HOXB9.01 and STAT6.01, according to MatInspector software analysis. Three SNPs were observed in the CRD-encoding region in HIV-1-infected and uninfected individuals: p.K313I, c.941C>T and c.983C>T. This study shows that mutations in the Langerin gene are present in the analysed populations at different genotypic and allelic frequencies. Further studies should be conducted to verify the role of these mutations in HIV-1 susceptibility.