Human T-cell Lymphotropic Virus Research Articles

New Prognostic Classification for Adult T Cell Lymphoma/Leukemia Based on Hypercalcemia and Neutrophil-to-Lymphocyte Ratio

▪Background: Adult T-cell lymphoma/leukemia (ATLL) represents a fatal disease epidemiologically linked to chronic infection of human T-cell lymphotropic virus type I (HTLV-I) with high incidence among native etnias from south-america. Most patients are stratified according to Shimoyama classification, however it is complex to use and not reliable to show prognostic information about the disease. Hypercalcemia is one of the most ominous factors related to the burden of disease and neutrophil-to-lymphocyte ratio (NLR) represents a systemic biomarker of inflamation. Our aim was to propose a simple score based on hypercalcemia and neutrophil-to-lymphocyte ratio for prognostic stratification among patients with ATLL.Methods: We reviewed 248 medical records from patients with ATLL diagnosed between 2008-2014 at the Instituto Nacional de Enfermedades Neoplasicas (Peru). Hypercalcemia was defined as ionic calcium > 1.32mmol/L (we score it as normal with 1 point and high with 2 points) and neutrophil-to-lymphocyte ratio ≤3 (1 point) or NLR >3 (2 points). Patients were assigned to high (4 points), Intermediate (3 points) and low risk group (2 points). Outcomes and survival differences were calculated by log-rank test.Results: Mean age was 56 years (39.5% were >60 years), no differences between males or females. Tuberculosis infection was founded on 12.5%. About 83% were in good status performance (Zubrod 0-2) and a worse status was related to high risk group (33%, p<0.001). According to Shimoyama classification we found: 38% Acute, 47% Lymphoma, 10% Smoldering and 5% Chronic subtypes. Most patients received a CHOP-based chemotherapy (71%) without differences between subgroups and overall response was 41% (CR:24% and PR:17%), we did not find differences between acute, lymphoma and smoldering subtypes, however most patients with smoldering subtype achieved complete remission (6 out 9). By other hand, complete response in low-risk was 33%, intermediate-risk 17% and high-risk group 9.7% (p<0.001). At 5 years follow-up, median overall survival in low-risk group was 14 months, 4 months for intermediate group and one month for high-risk group (Low vs Intermediate HR: 0.3, CI95%[0.2-0.5], p<0.001, Low vs High HR: 0.2, CI95%[0.1-0.3], p<0.001). We did not find survival differences between acute, lymphoma and chronic subtypes.Conclusion: We present a simple two-parameters classification based on hypercalcemia and neutrophil-to-lymphocyte ratio for adult t-cell leukemia/lymphoma with high impact on complete responses rates and overall survival. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Adult T-Cell Leukemia/Lymphoma: Clinical Characteristics and Outcome of Aggressive Subtypes Treated at a Tertiary Cancer Center

Introduction:Adult T-cell leukemia/lymphoma (ATLL) is a disease that develops in a small proportion of individuals who are chronically infected with human T-cell lymphotropic virus type 1 (HTLV-1). Infection is endemic in some parts of the world, Brazil included1.According to the Shimoyama classification, there are four ATLL subtypes: (1) acute, (2) lymphomatous, (3) chronic, and (4) smoldering2. The acute and lymphomatous subtypes are grouped together as aggressive subtypes and often appear with hypercalcemia, cutaneous lesions and visceral dysfunctions.To define a first line treatment for aggressive ATLL is challenging, as the disease is often refractory even to intensive chemotherapy. According to a meta-analysis, patients with the acute subtype should receive antiviral therapy with zidovudine (AZT) and interferon-alfa (INF) and patients with the lymphomatous subtype should receive chemotherapy, both followed by allogeneic stem cell transplantation (ASCT) when feasible3.The aim of this study is to describe the clinical and laboratory characteristics, as well as outcomes of patients with aggressive ATLL treated at a single center in Rio de Janeiro, Brazil.Methods: This is a retrospective study. All patients diagnosed with acute or lymphomatous ATLL (according to the Shymoiama classification) between January 2011 and January 2017 have been evaluated. Diagnosis criteria included positive serology for HTLV-1 and histologically or cytologically proven T-cell malignancy. All patients were treated and followed-up in the Hematology Department of Instituto Nacional de Cancer in Rio de Janeiro, Brazil.Statistical analyses were performed using SPSS software, version 21 (SPPS Inc., Chicago, IL, USA).Results: A total of 28 patients with aggressive ATLL were analyzed: patient characteristics are summarized in Table 1.Most patients (57%) were treated initially with chemotherapy (CT), usually CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) with 21-days intervals between cycles. Remaining patients were treated with antiviral therapy (AZT/INF). Treatment was considered adequate for the clinical subtype in 23 patients (82%). All patients received monthly intratechal chemotherapy.Complete response was achieved in 5 patients (18%) and partial response in 3 additional patients (11%), with an overall response rate of only 29%. Median survival time was 16.7 months (8 and 17 months for acute and lymphoma types, respectively, not statistically significant). The only factor associated with better survival was at least partial response to first line treatment (Fig 1). The main cause of death was progression of the primary disease.Only three patients (10%) were submitted to ASCT (two related and one unrelated). Two are alive one year after transplantation without evidence of the disease. The other patient died a few months after the transplantation of progressive disease.Discussion: Treatment of aggressive ATLL is challenging, as patients often appear with a heavy tumor burden and a disease refractory to primary treatment or quickly relapse after remission. A large recent Japanese study including 344 patients with aggressive ATLL showed survival times of 8.3 and 10.6 months for the acute and lymphomatous subtypes, respectivelly4. Despite the limitations of our study, including its retrospective nature and the small sample, our resultsprovide relevant information from cases of an endemic area with limited number of studies. At least a partial response to first line treatment is necessary for long term survival.Conclusion:Treatment of aggressive ATLL are ineffective and limited. The challenge is to develop therapeutic approaches with higher response rates and to increase the number of patients undergoing ASCT.References1 - Proietti FA, Carneiro-Proietti ABF, Catalan-Soares BC, et al. Global epidemiology of HTLV-1 infection and associated diseases. Oncogene 2005;24:6058-682 - Shimoyama M. Diagnostic criteria and classification of clinical subtypes of adult T-cell leukemia-lymphoma. Br J Haematol 1991;79:428-373 - Bazerbachi A, Plumelle Y, Ramos JC, et al. Meta-analysis on the use of zidovudine and interferon-alpha in adult T-cell leukemia/lymphoma showing improved survival in the leukemic subtypes. J Clin Oncol 2010;28:4177-834 - Katsuya H, Ishitsuka K, Utsunomiya A, et al. Treatment and survival among 1594 patients with ATL. Blood 2015;126:2570-2577. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

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 remainasymptomatic carriers (AC). Despite some mutations in the HTLV-1 genome appear to influence the outcome of HTLV-1, there are few studies that characterizemolecularly 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 conditionssince 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.

Virus-Driven Carcinogenesis.

Simple SummaryCarcinogens, causes of cancer, are usually invisible and therefore in vivo carcinogenesis is difficult to detect. Tumor viruses, definitive carcinogens, are also usually unremarkable, particularly due to latent infection. However, recent developments in tumor virology are unraveling how a single infected cell becomes a life-threatening cell population from a molecular perspective. The recognition and characterization of virus-driven carcinogenesis is the first step in the eradication of tumor virus-associated cancer.Cancer arises from the accumulation of genetic and epigenetic alterations. Even in the era of precision oncology, carcinogens contributing to neoplastic process are still an important focus of research. Comprehensive genomic analyses have revealed various combinations of base substitutions, referred to as the mutational signatures, in cancer. Each mutational signature is believed to arise from specific DNA damage and repair processes, including carcinogens. However, as a type of carcinogen, tumor viruses increase the cancer risk by alternative mechanisms, including insertional mutagenesis, viral oncogenes, and immunosuppression. In this review, we summarize virus-driven carcinogenesis to provide a framework for the control of malignant cell proliferation. We first provide a brief overview of oncogenic viruses and describe their implication in virus-related tumors. Next, we describe tumor viruses (HPV, Human papilloma virus; HBV, Hepatitis B virus; HCV, Hepatitis C virus; EBV, Epstein–Barr virus; Kaposi sarcoma herpesvirus; MCV, Merkel cell polyoma virus; HTLV-1, Human T-cell lymphotropic virus, type-1) and tumor virus-related cancers. Lastly, we introduce emerging tumor virus candidates, human cytomegalovirus (CMV), human herpesvirus-6 (HHV-6) and adeno-associated virus-2 (AAV-2). We expect this review to be a hub in a complex network of data for virus-associated carcinogenesis.

Comparison of Profiles of First Nations and Non-First Nations Children With Bronchiectasis Over Two 5-Year Periods in the Northern Territory, Australia

Although the burden of bronchiectasis is recognized globally, pediatric data are limited, particularly on trends over the years. Also, no published data exists regarding whether vitamin D deficiency or insufficiency and human T-cell lymphotropic virus type 1 (HTLV-1) infection, both found to be related to severe bronchiectasis in First Nations adults, also are important in children with bronchiectasis. Among children with bronchiectasis, (1) have the clinical and BAL profiles changed between two 5-year periods (period 1, 2007-2011; period 2, 2012-2016) and (b) are vitamin D deficiency or insufficiency, HTLV-1 infection, or both associated with radiologic severity of bronchiectasis? We analyzed the data from children with bronchiectasis prospectively enrolled at Royal Darwin Hospital, Australia, at the first diagnosis; that is, no child was included in both periods. Data collected include demographics, BAL, routine investigation bloods, and high-resolution CT scan of the chest evaluated using the Bhalla and modified Bhalla scores. The median age of the 299 children was 2.2 years (interquartile range, 1.5-3.7 years). One hundred sixty-eight (56%) were male and most were First Nations (92%). Overall, bronchiectasis was high over time, particularly among First Nations children. In the later period, numbers of non-First Nations children more than tripled, but did not reach statistical significance. In period 2 compared with period 1, fewer First Nations children demonstrated chronic cough (period 1, 61%; period 2, 47%; P= .03), and were younger, First Nations children were less likely to have received azithromycin (period 1, 42%; period 2, 21%; P< .001), and the BAL fluid of First Nations children showed lower Haemophilus influenzae and Moraxella catarrhalis infection. HTLV-1 infection was not detected, and vitamin D deficiency or insufficiency did not correlate with severity of bronchiectasis. Bronchiectasis remains high particularly among First Nations children. Important changes in their profiles that arguably reflect improvements were present, but overall, the profiles remained similar. Although vitamin D deficiency was uncommon, its role in children with bronchiectasis requires further evaluation. HTLV-1 infection was nonexistent and is unlikely to play any role in First Nations children with bronchiectasis.

Evaluation of iron, ferritin, copper, and ceruloplasmin along with proviral load in human T lymphotropic virus type 1-associated myelopathy.

Human T-cell lymphotropic virus type 1 (HTLV-1) infection can cause HTLV-I-associated myelopathy (HAM). In this study, we evaluated the levels of serum iron, ferritin, copper, and ceruloplasmin, and their correlations with HTLV-1 proviral load (PVL) and standard indices of HAM severity. In total, 114 subjects were recruited in this cross sectional study in Qaem Hospital, Mashhad, Iran between 2017 and 2018, including 36 HAM and 32 asymptomatic cases (ACs) and 46 healthy people (HSs). The clinical examination and evaluation of serum levels of biochemical factors and proviral load were performed. The PVL in HAM and ACs were 1835.49±382.81 and 280.97±67.41 copies/104 PBMCs, which statistically differed. Significant differences were also observed in plasma levels of iron, copper, and ceruloplasmin, among the three groups, while ferritin level was not considerably different. For HAM severity, the mean Osame motor disability scale (OMDS) and overactive bladder-validated-8-questionnaire (OABV-8) scores were 4.97±0.38 and 15.75±0.83, respectively, that had no significant correlations with the biochemical variables. Even though the studied elements in HAM group did not affect the severity of the disease, the levels of copper and ceruloplasmin might be determinants of the development and progression of HAM, as they are shown to play role in progression of other neurological diseases.

Effect of Teriflunomide on Cells From Patients With Human T-cell Lymphotropic Virus Type 1-Associated Neurologic Disease.

ObjectiveTo test the hypothesis that teriflunomide can reduce ex vivo spontaneous proliferation of peripheral blood mononuclear cells (PBMCs) from patients with human T-cell lymphotropic virus type 1 (HTLV-1)–associated myelopathy/tropical spastic paraparesis (HAM/TSP).MethodsPBMCs from patients with HAM/TSP were cultured in the presence and absence of teriflunomide and assessed for cell viability, lymphocyte proliferation, activation markers, HTLV-1 tax and HTLV-1 hbz messenger ribonucleic acid (mRNA) expression, and HTLV-1 Tax protein expression.ResultsIn culture, teriflunomide did not affect cell viability. A concentration-dependent reduction in spontaneous proliferation of PBMCs was observed with 25 μM (38.3% inhibition), 50 μM (65.8% inhibition), and 100 μM (90.7% inhibition) teriflunomide. The inhibitory effects of teriflunomide were detected in both CD8+ and CD4+ T-cell subsets, which are involved in the immune response to HTLV-1 infection and the pathogenesis of HAM/TSP. There was no significant change in HTLV-1 proviral load (PVL) or tax mRNA/Tax protein expression in these short-term cultures, but there was a significant reduction of HTLV-1 PVL due to inhibition of proliferation of CD4+ T cells obtained from a subset of patients with HAM/TSP.ConclusionsThese results suggest that teriflunomide inhibits abnormal T-cell proliferation associated with HTLV-1 infection and may have potential as a therapeutic option in patients with HAM/TSP.

Phenotypic and Functional Analyses Guiding Combination Immune Checkpoint Immunotherapeutic Strategies in HTLV-1 Infection.

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) develops in 1–5% of HTLV-1-infected individuals. Previous studies by us and others have shown that the expression of negative immune checkpoint receptors (NCRs) is significantly increased on CD8 T cells in various chronic viral infections and are associated with poor anti-viral immunity. We have previously identified the differential expression of NCRs on CD8 T cells in blood from patients with HAM/TSP and in central nervous system (CNS) tissues of HTLV-1 infected humanized mice and defined the association with neurological complications. In this study, we determined the co-expression patterns of several key NCRs (PD-1, TIGIT, TIM-3, and LAG-3) and their cognate ligands in HTLV-1 infection and assessed how combination strategies targeting these pathways would impact HTLV-1-specific CD8 T-cell effector functions as an approach to reduce CNS disease outcomes. We found that global CD8 T cells from HAM/TSP patients co-express multiple NCRs at significantly higher frequencies than asymptomatic carriers (AC). Moreover, NCR ligands (PVR and PD-LI) on both plasmacytoid and myeloid dendritic cells were also expressed at higher frequencies in HAM/TSP compared to AC. In both AC and HAM/TSP subjects, combination dual PD-L1/TIGIT or triple PD-L1/TIGIT/TIM-3 blockade with monoclonal antibodies resulted in increases in intracellular cytokine expression in CD8 T cells after virus stimulation, particularly CD107a, a marker of degranulation, and TNF-α, a key cytokine that can directly inhibit viral replication. Interestingly, almost all blockade combinations resulted in reduced IL-2+ HTLV-1-specific CD8 T cell frequencies in HAM/TSP subjects, but not in AC. These results define a novel combinatorial NCR immunotherapeutic blockade strategy to reduce HAM/TSP disease burden.

Revisiting Koch's postulate to determine the plausibility of viral transmission by human milk.

As breastfeeding is of utmost importance for child development and survival, identifying whether breast milk is a route of transmission for human viruses is critical.Based on the principle of Koch's postulate, we propose an analytical framework to determine the plausibility of viral transmission by breast milk. This framework is based on five criteria: viral infection in children receiving breast milk from infected mothers; the presence of virus, viral antigen, or viral genome in the breast milk of infected mothers; the evidence for the virus in breast milk being infectious; the attempts to rule out other transmission modalities; and the reproduction of viral transmission by oral inoculation in an animal model. We searched for evidence in published reports to determine whether the 5 criteria are fulfilled for 16 human viruses that are suspected to be transmissible by breast milk. We considered breast milk transmission is proven if all 5 criteria are fulfilled, as probable if 4 of the 5 criteria are met, as possible if 3 of the 5 criteria are fulfilled, and as unlikely if less than 3 criteria are met. Only five viruses have proven transmission through breast milk: human T‐cell lymphotropic virus 1, human immunodeficiency virus, human cytomegalovirus, dengue virus, and Zika virus. The other 11 viruses fulfilled some but not all criteria and were categorized accordingly.Our framework analysis is useful for guiding public health recommendations and for identifying knowledge gaps amenable to original experiments.

A significant association between CXCL10 -1447 A > G and IL18 -607 C > A gene polymorphism with human T-cell lymphotropic virus type 1 associated myelopathy/tropical spastic paraparesis (HAM-TSP), a case-control report from city of Mashhad, Iran.

Human T-cell lymphotropic virus type 1 (HTLV-1) is the first isolated retrovirus from humans, and 2-3% of infected individuals suffer from HTLV-1 associated myelopathy tropical spastic paraparesis (HAM-TSP). Previous studies indicated that the risk of HAM-TSP could be correlated with the individuals' genetic alterations. Mashhad is one of the areas infected with HTLV-1 in Iran. This study designed to examine the association between several important gene polymorphisms and HAM-TSP. Genotypes of 232 samples from controls, HTLV-1 carriers, and HAM-TSP patients were examined for FAS-670 (A > G), CXCL10-1447 (A > G), Foxp3-3279 (C > A), IL-18 -137 (C > G), and IL-18 -607 (C > A) gene polymorphisms by different polymerase chain reaction (PCR) techniques. A non-significant association was observed between FAS-670 A > G, Foxp3-3279 C > A, and IL-18 -137 C > G gene polymorphisms and HAM-TSP. Nevertheless, a significant (P<0.001) association between CXCL10-1447 A > G and IL-18 -607 C > A gene polymorphisms with HAM-TSP was observed in our study population. As previous studies revealed that the CXCL10 level in the cerebrospinal fluid of HAM-TSP patients was associated with the disease progression, and as we noticed, a direct association was observed between CXCL10-1447 A > G polymorphism and HAM-TSP. These polymorphisms might be recommended as a valuable prediction criterion for the severity of the disease. The contradiction between our findings and other studies regarding IL-18 -607 C > A gene polymorphism might be associated with various factors such as genotypes frequency in diverse races and population heterogeneity in the city of Mashhad.

Evaluation of the Seroprevalence of Infectious Diseases in 2,445 in vitro Fertilization Cycles.

To evaluate the seroprevalence of positive markers for syphilis, human immunodeficiency virus (HIV) I and II, human T cell lymphotropic virus (HTLV) I and II, and hepatitis B and C among women undergoing in vitro fertilization (IVF). We conducted a retrospective analysis among patients who underwent IVF, between January 2013 and February 2016, and who had complete screening records. We analyzed 1,008 patients who underwent IVF, amounting to 2,445 cycles. Two patients (0.2%) tested positive for HIV I and II and none for HTLV I and II. Three patients (0.3%) had positive screening for syphilis, and two (0.2%) had positive hepatitis C antibody test (anti-HCV). A positive hepatitis B virus surface antigen (HbsAg) test was observed in 4 patients (0.4%), while 47 (4.7%) patients were positive for IgG antibody to hepatitis B core antigen (anti-HbC IgG), and only 1 (0.1%) was positive for IgM antibody to hepatitis B core antigen (anti-HbC IgM). The anti-HbS test was negative in 659 patients (65.3%). Only 34.7% of the patients had immunity against the Hepatitis B virus. Patients with an anti-HbS negative result were older than those with a hepatitis B test (anti-HbS) positive result (36.3 versus 34.9; p < 0.001). The present study showed lower infection rates than the Brazilian ones for the diseases studied in patients undergoing IVF. Only a few patients were immunized against hepatitis B.

Evaluation of the Inflammatory Cytokines and IL-10 Network in Individuals Co-infected With Human T-Cell Lymphotropic Virus and Hepatitis C Virus (HTLV/HCV).

BackgroundCo-infection between the human T-cell lymphotropic virus (HTLV) and the hepatitis C virus (HCV) can modify the natural history of HCV infection. The aim of this study was to describe the inflammatory cytokines and IL-10 network in patients co-infected with HTLV and HCV viruses in Bahia, Brazil.MethodsSamples from 31 HTLV/HCV co-infected individuals and 27 HCV monoinfected individuals were evaluated. IFN-γ, TNF-α, IL-10, IL-8, and IL-1 cytokines were quantified by ELISA. Clinical, laboratory data were obtained from patient records. Serum levels of the cytokines were log10-transformed and data mining was performed using Z-score statistics and correlation analysis.ResultsCo-infected individuals presented a tendency toward higher production of INF-γ compared to the HCV monoinfected group. Regarding cytokine pairs, there was a positive correlation (P-value < 0.05) between IL-1 and IL-8 in the HTLV/HCV co-infected group and uninfected controls, and two correlations in the HCV mono-infected group IL-8 – IL10 and IL- INF-γ – IL-10 pairs. There was no significant difference between the groups for the other parameters analyzed.ConclusionThe results presented herein indicated that HTLV/HCV co-infection was associated with a trend in IFN-γ production while HCV-infected individuals presented a positive correlation with both inflammatory cytokines (IL-8 and IFN-γ) and the regulatory cytokine IL-10.

Screening for Human T-Cell Lymphotropic Virus (HTLV) in Pregnant Women in the Peruvian Amazon and Systematic Review with Meta-Analysis of HTLV Infection in Peru.

Background. Human T-cell lymphotropic virus type 1 (HTLV-1) is responsible for tropical spastic paraparesis and HTLV-1-associated leukemia/lymphoma. The infection is endemic in some areas of Peru, but its prevalence in the Peruvian Amazon is not well established. We aimed to assess the seroprevalence of HTLV-1 infection in pregnant women in the Peruvian Amazon. Moreover, we performed a systematic literature review and meta-analysis of the seroprevalence of HTLV infection in Peru. (2) Methods. This is a prospective cross-sectional study involving pregnant women attending health centers in the city of Iquitos, Peru, in May and June 2019. The presence of antibodies against HTLV-1 was assessed using ELISA (HTLV I + II ELISA recombinant v.4.0, Wiener lab, Rosario, Argentina). Positive cases were confirmed by Western Blot and HTLV-1 proviral load. (3) Results. The study included 300 pregnant women with a mean age of 26 years (standard deviation [SD] 6.4). Five patients were diagnosed with HTLV-1 infection (prevalence 1.7%, 95% confidence interval (CI) 0.7% to 3.8%). Pregnant women with HTLV-1 infection were discretely younger (mean age 22.6 [SD 22.6] vs. 26.8 [SD 6.3]; p = 0.128). None of the five women had been transfused, and all were asymptomatic. Two (40%) also had a positive serology for Strongyloides, but larvae were not detected in any of the parasitological stool studies. The systematic review component identified 40 studies, which showed that the prevalence of HTLV infection in the general population was 2.9% (95% CI 1.2% to 5.3%) and in women of childbearing age, 2.5% (95% CI 1.2% to 4.0%). (4) Conclusion. The prevalence of HTLV-1 in the Peruvian Amazon basin is about 1.7%, indicating an endemic presence. Screening for HTLV-1 in prenatal care is warranted.

Comprehensive genomic analysis identifying heterogeneity in peripheral T‐cell lymphoma

Peripheral T‐cell lymphoma (PTCL) is a heterogeneous entity generally with a poor prognosis. Recent genomic analyses have characterized genomic alterations and described gene expression profiling and epigenetic mechanisms in PTCL, leading to reveal molecular pathophysiology in detail. One of several important findings is that heterogeneities exist in both the disease and in individuals. Among PTCL subtypes, adult T‐cell leukemia/lymphoma (ATLL) and peripheral T‐cell lymphoma, not otherwise specified (PTCL‐NOS) are common in Japan. ATLL is an incurable T‐cell malignancy induced by human T‐cell lymphotropic virus type 1 (HTLV‐1). The global genomics of ATLL can be summarized as alterations involving T‐cell receptor (TCR) signaling and immune escape mechanisms. This highlights the fact that ATLL is a viral‐mediated T‐cell malignancy. Interestingly, several previous studies have found that the genomics of ATLL differ according to geographical region and age at diagnosis, suggesting disease heterogeneity, though they share HTLV‐1 infection as initial disease hit. Clonal expansion of the cells acquired by somatic mutations in ATLL‐related genes is identified in a part of HTLV‐1 carriers who developed ATLL later. The risk for ATLL may be updated based on findings in detail. PTCL‐NOS is a heterogeneous disease type of T‐cell lymphoma that does not correspond to any other type of PTCL. Several studies have stratified PTCL‐NOS according to transcriptional, genomic, microenvironmental, and clinical aspects. These kinds of analysis from multiple aspects are useful to understand the heterogeneous group. These efforts will help guide suitable translational research to target PTCL.

Inhibiting HTLV-1 Protease: A Viable Antiviral Target.

Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that can cause severe paralytic neurologic disease and immune disorders as well as cancer. An estimated 20 million people worldwide are infected with HTLV-1, with prevalence reaching 30% in some parts of the world. In stark contrast to HIV-1, no direct acting antivirals (DAAs) exist against HTLV-1. The aspartyl protease of HTLV-1 is a dimer similar to that of HIV-1 and processes the viral polyprotein to permit viral maturation. We report that the FDA-approved HIV-1 protease inhibitor darunavir (DRV) inhibits the enzyme with 0.8 μM potency and provides a scaffold for drug design against HTLV-1. Analogs of DRV that we designed and synthesized achieved submicromolar inhibition against HTLV-1 protease and inhibited Gag processing in viral maturation assays and in a chronically HTLV-1 infected cell line. Cocrystal structures of these inhibitors with HTLV-1 protease highlight opportunities for future inhibitor design. Our results show promise toward developing highly potent HTLV-1 protease inhibitors as therapeutic agents against HTLV-1 infections.

Extracellular vesicles from HTLV-1 infected cells modulate target cells and viral spread

BackgroundThe Human T-cell Lymphotropic Virus Type-1 (HTLV-1) is a blood-borne pathogen and etiological agent of Adult T-cell Leukemia/Lymphoma (ATLL) and HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). HTLV-1 has currently infected up to 10 million globally with highly endemic areas in Japan, Africa, the Caribbean and South America. We have previously shown that Extracellular Vesicles (EVs) enhance HTLV-1 transmission by promoting cell–cell contact.ResultsHere, we separated EVs into subpopulations using differential ultracentrifugation (DUC) at speeds of 2 k (2000×g), 10 k (10,000×g), and 100 k (100,000×g) from infected cell supernatants. Proteomic analysis revealed that EVs contain the highest viral/host protein abundance in the 2 k subpopulation (2 k > 10 k > 100 k). The 2 k and 10 k populations contained viral proteins (i.e., p19 and Tax), and autophagy proteins (i.e., LC3 and p62) suggesting presence of autophagosomes as well as core histones. Interestingly, the use of 2 k EVs in an angiogenesis assay (mesenchymal stem cells + endothelial cells) caused deterioration of vascular-like-tubules. Cells commonly associated with the neurovascular unit (i.e., astrocytes, neurons, and macrophages) in the blood–brain barrier (BBB) showed that HTLV-1 EVs may induce expression of cytokines involved in migration (i.e., IL-8; 100 k > 2 k > 10 k) from astrocytes and monocyte-derived macrophages (i.e., IL-8; 2 k > 10 k). Finally, we found that EVs were able to promote cell–cell contact and viral transmission in monocytic cell-derived dendritic cell. The EVs from both 2 k and 10 k increased HTLV-1 spread in a humanized mouse model, as evidenced by an increase in proviral DNA and RNA in the Blood, Lymph Node, and Spleen.ConclusionsAltogether, these data suggest that various EV subpopulations induce cytokine expression, tissue damage, and viral spread.

Point-of-Care System for HTLV-1 Proviral Load Quantification by Digital Mediator Displacement LAMP.

This paper presents a universal point-of-care system for fully automated quantification of human T-cell lymphotropic virus type 1 (HTLV-1) proviral load, including genomic RNA, based on digital reverse RNA transcription and c-DNA amplification by MD LAMP (mediator displacement loop-mediated isothermal amplification). A disposable microfluidic LabDisk with pre-stored reagents performs automated nucleic acid extraction, reaction setup, emulsification, reverse transcription, digital DNA amplification, and quantitative fluorogenic endpoint detection with universal reporter molecules. Automated nucleic acid extraction from a suspension of HTLV-1-infected CD4+ T-lymphocytes (MT-2 cells) yielded 8 ± 7 viral nucleic acid copies per MT-2 cell, very similar to the manual reference extraction (7 ± 2 nucleic acid copies). Fully automated sample processing from whole blood spiked with MT-2 cells showed a comparable result of 7 ± 3 copies per MT-2 cell after a run time of two hours and 10 min.

Prevalence and evolutionary analyses of human T-cell lymphotropic virus in Guangdong province, China: Transcontinental and Japanese subtype lineages dominate the prevalence.

To systematically characterize the prevalence and evolution of human T-cell lymphotropic virus (HTLV) infection among voluntary blood donors (BDs) in Guangdong province, China. A three-year survey for HTLV epidemiology among BDs was performed in Guangdong during 2016-2018. Anti-HTLV-1/2 was screened by ELISA and ECLIA, and subsequently confirmed by western blot (WB) and nucleic acid testing (NAT). The prevalence of HTLV in donors from different cities was calculated. The identified HTLV-positive cases were phylogenetically genotyped and analyzed in a Bayesian phylogenetic framework. Among 3,262,271 BDs, 59 were confirmed positive for HTLV-1 (1.81 per 100,000) and no HTLV-2 infection was found. The prevalence of HTLV-1 varied significantly among 21 cities in Guangdong province, China. The highest prevalence was found in donors from Shanwei (13.94 per 100,000), which is a coastal city in eastern Guangdong. Viral genomic sequences genotyped from 55 HTLV-1 carriers showed that 39 were transcontinental subtype and 16 were Japanese subtype. Specially, 13 out of 39 transcontinental subtype sequences were characterized with L55P mutation and 21 out of 55 sequences were characterized with L19F mutation in viral gp46 protein. The L55P mutation seemed be specific to eastern Asia since it only presented in the sequences from Japan, mainland China, and Taiwan. Phylogenetic analysis of gp46 gene shows that HTLV-1a may have been introduced to Guangdong through four different introduction events and formed major transmission clusters: clades I(13,602 years ago), II(16, 010 years ago), III(15,639 years ago) and IV(16,517 years ago). In general, Guangdong is considered to be a low-prevalence region for HTLV-1 infection, but the prevalence is significantly higher in Shanwei city. Transcontinental and Japanese subtype lineages dominate the prevalence in Guangdong. In terms of blood safety, HTLV antibody screening for first-time blood donors can effectively reduce the risk of HTLV transmission.

Human T-cell lymphotropic virus type 1 transmission dynamics in rural villages in the Democratic Republic of the Congo with high nonhuman primate exposure.

The Democratic Republic of the Congo (DRC) has a history of nonhuman primate (NHP) consumption and exposure to simian retroviruses yet little is known about the extent of zoonotic simian retroviral infections in DRC. We examined the prevalence of human T-lymphotropic viruses (HTLV), a retrovirus group of simian origin, in a large population of persons with frequent NHP exposures and a history of simian foamy virus infection. We screened plasma from 3,051 persons living in rural villages in central DRC using HTLV EIA and western blot (WB). PCR amplification of HTLV tax and LTR sequences from buffy coat DNA was used to confirm infection and to measure proviral loads (pVLs). We used phylogenetic analyses of LTR sequences to infer evolutionary histories and potential transmission clusters. Questionnaire data was analyzed in conjunction with serological and molecular data. A relatively high proportion of the study population (5.4%, n = 165) were WB seropositive: 128 HTLV-1-like, 3 HTLV-2-like, and 34 HTLV-positive but untypeable profiles. 85 persons had HTLV indeterminate WB profiles. HTLV seroreactivity was higher in females, wives, heads of households, and increased with age. HTLV-1 LTR sequences from 109 persons clustered strongly with HTLV-1 and STLV-1 subtype B from humans and simians from DRC, with most sequences more closely related to STLV-1 from Allenopithecus nigroviridis (Allen's swamp monkey). While 18 potential transmission clusters were identified, most were in different households, villages, and health zones. Three HTLV-1-infected persons were co-infected with simian foamy virus. The mean and median percentage of HTLV-1 pVLs were 5.72% and 1.53%, respectively, but were not associated with age, NHP exposure, village, or gender. We document high HTLV prevalence in DRC likely originating from STLV-1. We demonstrate regional spread of HTLV-1 in DRC with pVLs reported to be associated with HTLV disease, supporting local and national public health measures to prevent spread and morbidity.

Global expression of noncoding RNome reveals dysregulation of small RNAs in patients with HTLV-1\u2013associated adult T-cell leukemia: a pilot study

BackgroundAdult T cell lymphoma/leukemia (ATLL) is a peripheral T-cell neoplasm caused by human T-cell lymphotropic virus-1 (HTLV-1). Small RNAs (sRNAs), including microRNAs (miRNAs), play a pivotal role in the initiation and development of hematological malignancies and may represent potential therapeutic target molecules. However, little is known about how these molecules impact the pathogenesis of ATLL. In this study, we aimed to identify sRNA expression signatures associated with ATLL and to investigate their potential implication in the pathophysiology of the disease.MethodsSmall-RNAseq analysis was performed in peripheral blood mononuclear cells from HTLV-1- associated ATLL (n = 10) in comparison to asymptomatic carriers (n = 8) and healthy controls (n = 5). Sequencing was carried out using the Illumina MiSeq platform, and the deregulation of selected miRNAs was validated by real-time PCR. Pathway analyses of most deregulated miRNA were performed and their global profiling was combined with transcriptome data in ATLL.ResultsThe sequencing identified specific sRNAs signatures associated with ATLL patients that target pathways relevant in ATLL, such as the transforming growth factor-(βTGF-β), Wnt, p53, apoptosis, and mitogen-activated protein kinase (MAPK) signaling cascades. Network analysis revealed several miRNAs regulating highly connected genes within the ATLL transcriptome. miR-451-3p was the most downregulated miRNA in active patients.ConclusionsOur findings shed light on the expression of specific sRNAs in HTLV-1 associated ATLL, which may represent promising candidates as biomarkers that help monitor the disease activity.