Identification of miRnas with possible prognostic roles for HAM/TSP.

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropic spastic paraparesis (HAM/TSP) is an insidiously progressive spinal cord disease for which there is no effective treatment. There is great interest in developing potential biomarkers to predict the pathogenesis of HAM/TSP disease. In this study, Illumina Massive Parallel Sequencing (MPS) technology was used to investigate the cellular global noncoding RNAome expression profile in HAM/TSP patients (n = 10), asymptomatic HTLV-1-infected carriers (ASP, n = 8), and a second group of healthy controls (n = 5). Various bioinformatics tools were used to align, annotate, and profile the sRNA-MPS reads. Among the 402 sRNAs detected, 251 were known and 50 were potentially novel sRNAs in the HAM and ASP groups compared with the HC group. Sixty-eight known sRNAs were significantly different between the ASP and HAM groups. Eighty-eight mature miRNAs were downregulated in subjects from HAM compared with ASP. Three of these miRs (hsa-miR-185-5p, 32-5p, and 192-5p) have the potential to be used as biomarkers for predicting the pathogenesis of HAM/TSP. The seven most deregulated miRs target genes have been associated with a variety of biological processes and molecular functions. The reactome pathways relevant to our findings provide a rich source of data and offer the opportunity to better understand sRNA regulation and function in HTLV-1 pathophysiology. To the best of our knowledge, this study is the first to demonstrate evaluates sRNAs in HTLV-1 patients with HAM/TSP.

The mirror like expression of genes involved in the FOXO signaling pathway could be effective in the pathogenesis of human lymphotropic virus type 1 (HTLV-1) through disruption of the downstream pathways.

OBJECTIVES: Human lymphotropic virus type 1 (HTLV-1) is the cause of two major diseases, ATLL and HAM/TSP in a percentage of carriers. Despite progress in understanding the pathogenesis of these two diseases, the exact pathogenesis mechanism is still not well understood. High-throughput technologies have revolutionized medical research. This study aims to investigate the mechanism of pathogenesis of these two diseases using the results of high-throughput analysis of microarray datasets. RESULTS: A total of 100 differentially expressed genes were found between ATLL and HAM/TSP. After constructing protein-protein network and further analyzing, proteins including ATM, CD8, CXCR4, PIK3R1 and CD2 were found as the hub ones between ATLL and HAM/TSP. Finding the modules of the subnetwork revealed the enrichment of two common pathways including FOXO signaling pathway and Cell cycle with two common genes including ATM and CDKN2D. Unlike ATLL, ATM gene had higher expressions in HAM/TSP patients. The expression of CDKN2D was increased in ATLL patients. The results of this study could be helpful for understanding the pathogenic mechanism of these two diseases in the same signaling pathways.

Pathogenicity and virulence of human T lymphotropic virus type-1 (HTLV-1) in oncogenesis: adult T-cell leukemia/lymphoma (ATLL).

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive malignancy of CD4+ T lymphocytes caused by human T lymphotropic virus type-1 (HTLV-1) infection. HTLV-1 was brought to the World Health Organization (WHO) and researchers to address its impact on global public health, oncogenicity, and deterioration of the host immune system toward autoimmunity. In a minority of the infected population (3-5%), it can induce inflammatory networks toward HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), or hijacking the infected CD4+ T lymphocytes into T regulatory subpopulation, stimulating anti-inflammatory signaling networks, and prompting ATLL development. This review critically discusses the complex signaling networks in ATLL pathogenesis during virus-host interactions for better interpretation of oncogenicity and introduces the main candidates in the pathogenesis of ATLL. At least two viral factors, HTLV-1 trans-activator protein (TAX) and HTLV-1 basic leucine zipper factor (HBZ), are implicated in ATLL manifestation, interacting with host responses and deregulating cell signaling in favor of infected cell survival and virus dissemination. Such molecules can be used as potential novel biomarkers for ATLL prognosis or targets for therapy. Moreover, the challenging aspects of HTLV-1 oncogenesis introduced in this review could open new venues for further studies on acute leukemia pathogenesis. These features can aid in the discovery of effective immunotherapies when reversing the gene expression profile toward appropriate immune responses gradually becomes attainable.

Development of a Novel HTLV-1 Protease: Human Fcγ1 Recombinant Fusion Molecule in the CHO Eukaryotic Expression System.

Human T-cell leukaemia virus type 1 (HTLV-1) is the causative agent of two life-threatening diseases, adult T cell leukaemia/lymphoma (ATLL), and HTLV-1-associated myelopathy/tropical spastic (HAM/TSP). HTLV-1 protease (HTLV-1-PR) is an aspartic protease that represents a promising target for therapeutic purposes like human immunodeficiency virus-PR inhibitors (HIV-PR). Therefore, in this study, the human Fc fusion recombinant-PR (HTLV-1-PR:hFcγ1) was designed and expressed for two applications, finding a blocking substrate as a potential therapeutic or a potential subunit peptide vaccine. The PCR amplified DNA sequences encoding the HTLV-1-PR from the MT2-cell line using specific primers with restriction enzyme sites of Not1 and Xba1. The construct was then cloned to pTZ57R/T TA plasmid and, after confirming the PR sequence, subcloned into the pDR2ΔEF1α Fc-expression vector to create pDR2ΔEF1α.HTLV-1-PR:hFcγ1. The integrity of recombinant DNA was confirmed by sequencing to ensure that the engineered construct was in the frame. The recombinant fusion protein was then produced in the Chinese hamster ovary cell (CHO) system and was purified from its supernatant using HiTrap-rPA column affinity chromatography. Then, the immunofluorescence assay (IFA) co-localisation method showed that HTLV-1-PR:hFc recombinant fusion protein has appropriate folding as it binds to the anti-Fcγ antibody; the Fcγ1 tag participates to have HTLV-1-PR:hFcγ1 as a dimeric secretory protein. The development and production of HTLV-1-PR can be used to find a blocking substrate as a potential therapeutic molecule and apply it in an animal model to assess its immunogenicity and potential protection against HTLV-1 infection.

Particularities of Neurological Manifestations in Adult T-Cell Leukemia/Lymphoma: Need for a Multidisciplinary Approach-A Narrative Review.

ATL is a rare but a highly aggressive T-cell neoplasm associated with human T-cell leukemia virus-1 (HTLV-1) infection. Human T-cell lymphotropic virus type-1 (HTLV-1) is a oncogenic retrovirus responsible for the development of adult T-cell leukemia (ATL), but also for other non-malignant diseases, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1 has a higher prevalence in Japan, the Caribbean, South America, intertropical Africa, Romania, and northern Iran. ATL patients can have an extensive spectrum of neurological manifestations. Numerous factors can be implicated, such as central nervous system infiltrates, neurolymphomatosis, complications to medication or allogeneic stem cell transplantation, HAM/TSP, infections, metabolic disturbances. The neurological complications are not always easy to recognize and treat. Thus, this review underlines the necessity of a multidisciplinary approach in ATL patients with neurological symptomatology.

Establishment of a Cynomolgus Macaque Model of Human T-Cell Leukemia Virus Type 1 (HTLV-1) Infection by Direct Inoculation of Adult T-Cell Leukemia Patient-Derived Cell Lines for HTLV-1 Infection.

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). However, the precise mechanisms leading to HTLV-1 chronic infection and the onset of the diseases have remained unclear, and effective vaccines for inhibiting the infection and the progression of pathogenesis have therefore not been developed. The use of a nonhuman primate (NHP) model is thought to be important for revealing the mechanisms of the progressive status and for the development of prevention procedures. In this study, we developed a cynomolgus macaque (CM) model of HTLV-1 infection by direct intravenous inoculation of HTLV-1-producing cells derived from ATL patients. The cell line used for infection, ATL-040, was selected as the most infectious one in our cell line library. CMs inoculated intravenously with 1 × 108 ATL-040 cells per animal became persistently infected with HTLV-1, as shown by the HTLV-1 provirus load (PVL) in peripheral blood mononuclear cells and HTLV-1-specific antibodies (2/2 animals). One CM inoculated intravenously with 1 × 107 ATL-040 cells did not have detectable PVLs despite the fact that anti-HTLV-1 antibodies were maintained for more than 2 years. Furthermore, immunological approaches, including CD8+ T cell depletion prior to infection (3/3 animals) and intrathecal inoculation (3/3 animals), led to increased proviral loads in the cynomolgus monkeys. The present method and the cynomolgus monkey model of HTLV-1 infection will be beneficial for immunological and virological studies on HTLV-1 aiming at the development of anti-HTLV-1 prophylactic vaccines and therapy drugs. IMPORTANCE HTLV-1 was discovered in the 1980s as the causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. However, the precise mechanisms leading to HTLV-1 chronic infection and the onset of the diseases still remain unidentified. Thus, no effective vaccines to inhibit the infection and the progressive of pathogenesis have been developed. The use of appropriate animal models is essential for understanding HTLV-1 infection and pathogenesis. In order to establish a new nonhuman primate model for studies on HTLV-1 infection, cynomolgus monkeys were infected with HTLV-1 under a variety of experimental conditions. Our method, using a cell line generated from an ATL patient as a source of HTLV-1, was able to establish HTLV-1 infection in monkeys with a 100% success rate. This cynomolgus macaque model of HTLV-1 infection will contribute to the elucidation of HTLV-1 infection and its associated disease development.

T cell receptor repertoire analysis in HTLV-1-associated diseases.

Human T lymphotropic virus 1 (HTLV-1) is a human retrovirus identified as the causative agent in adult T-cell leukemia/lymphoma (ATL) and chronic-progressive neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1 is estimated to infect between 5-20 million people worldwide, although most infected individuals remain asymptomatic. HTLV-1 infected persons carry an estimated lifetime risk of approximately 5% of developing ATL, and between 0.25% and 1.8% of developing HAM/TSP. Most HTLV-1 infection is detected in CD4+ T cells in vivo which causes the aggressive malignancy in ATL. In HAM/TSP, the increase of HTLV-1 provirus induces immune dysregulation to alter inflammatory milieu, such as expansion of HTLV-1-specific CD8+ T cells, in the central nervous system of the infected subjects, which have been suggested to underlie the pathogenesis of HAM/TSP. Factors contributing to the conversion from asymptomatic carrier to disease state remain poorly understood. As such, the identification and tracking of HTLV-1-specific T cell biomarkers that may be used to monitor the progression from primary infection to immune dysfunction and disease are of great interest. T cell receptor (TCR) repertoires have been extensively investigated as a mechanism of monitoring adaptive T cell immune response to viruses and tumors. Breakthrough technologies such as single-cell RNA sequencing have increased the specificity with which T cell clones may be characterized and continue to improve our understanding of TCR signatures in viral infection, cancer, and associated treatments. In HTLV-1-associated disease, sequencing of TCR repertoires has been used to reveal repertoire patterns, diversity, and clonal expansions of HTLV-1-specific T cells capable of immune evasion and dysregulation in ATL as well as in HAM/TSP. Conserved sequence analysis has further been used to identify CDR3 motif sequences and exploit disease- or patient-specificity and commonality in HTLV-1-associated disease. In this article we review current research on TCR repertoires and HTLV-1-specific clonotypes in HTLV-1-associated diseases ATL and HAM/TSP and discuss the implications of TCR clonal expansions on HTLV-1-associated disease course and treatments.

Evaluation of antioxidant status and oxidative stress markers in HTLV-1 infected individuals: correlation with the severity of virus-induced complications.

Introduction. Human T-cell lymphotropic virus type 1 (HTLV-1), a well-known member of the retroviridae family, potentially causes serious outcomes including adult T-cell leukaemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM-TSP). Oxidative stress plays a key role in progression and clinical exacerbation of several chronic infections. We have previously shown a reduction in serum total antioxidant capacity (TAC) during HTLV-1 infection and this study was set out to investigate the reasons for TAC reduction.Hypothesis/Gap Statement. Oxidant/antioxidant imbalance during HTLV-1 infection may result from disruptions in oxidant levels or antioxidant defence system.Aim. This study aimed to analyse the key enzymes and oxidant molecules playing important roles in virus-induced oxidative stress.Methodology. We measured serum activities of the major antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) as well as serum concentrations of the main oxidant markers: nitric oxide (NO) and malondialdehyde (MDA). Totally 40 HTLV-1 infected patients and 40 healthy controls were enrolled in this study. The patient group consisted of chronic carriers and patients with HAM-TSP (N=20).Results. The current study found that serum levels of MDA and NO were significantly higher in patient groups particularly in HAM-TSP patients (P<0.05). In addition, a reductive trend was observed in the serum activities of CAT, SOD, and GPX in HTLV-1 infected patients compared with healthy controls (P<0.05).Conclusion. Reduced activities of CAT, SOD, and GPX antioxidant enzymes along with the observed elevated concentrations of oxidant molecules may contribute to oxidative stress and worse outcomes during HTLV-1 infection.

Cardiovascular risk factors and brain white matter lesions in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).

The origin of brain white matter lesion found in HTLV-1-associated myelopathy (HAM/TSP) remains undefined. We investigated the association between white matter lesions in HAM/TSP with cardiovascular risk factors. The group of 40 patients with HAM/TSP included 60% females and mean age of 58.6 ± 8 years old. The probability of 10-year cardiovascular disease was low in 53%, moderate in 38%, and high in 10% of the patients. There was no difference between the cardiovascular risk factors in HAM/TSP patients with and without brain lesions (p > 0.05). Our data suggest that the brain white matter abnormalities are not associated to increased cardiovascular risk in HAM/TSP.

Clinical and Public Health Implications of Human T-Lymphotropic Virus Type 1 Infection.

Human T-lymphotropic virus type 1 (HTLV-1) is estimated to affect 5 to 10 million people globally and can cause severe and potentially fatal disease, including adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The burden of HTLV-1 infection appears to be geographically concentrated, with high prevalence in discrete regions and populations. While most high-income countries have introduced HTLV-1 screening of blood donations, few other public health measures have been implemented to prevent infection or its consequences. Recent advocacy from concerned researchers, clinicians, and community members has emphasized the potential for improved prevention and management of HTLV-1 infection. Despite all that has been learned in the 4 decades following the discovery of HTLV-1, gaps in knowledge across clinical and public health aspects persist, impeding optimal control and prevention, as well as the development of policies and guidelines. Awareness of HTLV-1 among health care providers, communities, and affected individuals remains limited, even in countries of endemicity. This review provides a comprehensive overview on HTLV-1 epidemiology and on clinical and public health and highlights key areas for further research and collaboration to advance the health of people with and at risk of HTLV-1 infection.

Cerebral and spinal cord changes observed through magnetic resonance imaging in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis: a systematic review.

To verify brain and spinal changes using magnetic resonance imaging in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis. This was a systematic review. The descriptors used were tropical spastic paraparesis and magnetic resonance image. The keyword HTLV-1-associated myelopathy was also used. Twenty-three articles were included: 16 detected brain changes and 18 detected spinal changes. White matter lesions were the most frequent finding in the brain. Brain injuries were most frequently identified in the periventricular region, in the subcortical region, in the centrum semiovale, in the brain stem, and corpus callosum. Atrophy was the most frequent finding of the spinal cord, affecting the thoracic and cervical regions, and was associated with a longer evolution of myelopathy. White matter lesions in these regions were also observed. Cortical white matter lesions and thoracic spinal cord atrophy were the most frequently reported changes in patients with HTLV-1-associated myelopathy.

Cryo-EM structure of the deltaretroviral intasome in complex with the PP2A regulatory subunit B56γ.

Human T-cell lymphotropic virus type 1 (HTLV-1) is a deltaretrovirus and the most oncogenic pathogen. Many of the ~20 million HTLV-1 infected people will develop severe leukaemia or an ALS-like motor disease, unless a therapy becomes available. A key step in the establishment of infection is the integration of viral genetic material into the host genome, catalysed by the retroviral integrase (IN) enzyme. Here, we use X-ray crystallography and single-particle cryo-electron microscopy to determine the structure of the functional deltaretroviral IN assembled on viral DNA ends and bound to the B56γ subunit of its human host factor, protein phosphatase 2 A. The structure reveals a tetrameric IN assembly bound to two molecules of the phosphatase via a conserved short linear motif. Insight into the deltaretroviral intasome and its interaction with the host will be crucial for understanding the pattern of integration events in infected individuals and therefore bears important clinical implications.

Human T-lymphotropic virus type 1 (HTLV-1) and cellular immune response in HTLV-1-associated myelopathy/tropical spastic paraparesis.

Human T-lymphotropic virus type 1 (HTLV-1) is associated with adult T cell leukemia/lymphoma and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP is an inflammatory disease of the spinal cord and clinically characterized by progressive spastic paraparesis, urinary incontinence, and mild sensory disturbance. The interaction between the host immune response and HTLV-1-infected cells regulates the development of HAM/TSP. HTLV-1 preferentially infects CD4+ T cells and is maintained by proliferation of the infected T cells. HTLV-1-infected cells rarely express viral antigens in vivo; however, they easily express the antigens after short-term culture. Therefore, such virus-expressing cells may lead to activation and expansion of antigen-specific T cell responses. Infected T cells with HTLV-1 and HTLV-1-specific CD8+ cytotoxic T lymphocytes invade the central nervous system and produce various proinflammatory cytokines and chemokines, leading to neuronal damage and degeneration. Therefore, cellular immune responses to HTLV-1 have been considered to play important roles in disease development of HAM/TSP. Recent studies have clarified the viral strategy for persistence in the host through genetic and epigenetic changes by HTLV-1 and host immune responses including T cell function and differentiation. Newly developed animal models could provide the opportunity to uncover the precise pathogenesis and development of clinically effective treatment. Several molecular target drugs are undergoing clinical trials with promising efficacy. In this review, we summarize recent advances in the immunopathogenesis of HAM/TSP and discuss the perspectives of the research on this disease.

Mortality and risk of progression to adult T cell leukemia/lymphoma in HTLV-1-associated myelopathy/tropical spastic paraparesis.

Human T cell leukemia virus 1 (HTLV-1) causes the functionally debilitating disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) as well as adult T cell leukemia lymphoma (ATLL). Although there were concerns that the mortality of HAM/TSP could be affected by the development of ATLL, prospective evidence was lacking in this area. In this 5-y prospective cohort study, we determined the mortality, prevalence, and incidence of ATLL in 527 HAM/TSP patients. The standard mortality ratio of HAM/TSP patients was 2.25, and ATLL was one of the major causes of death (5/33 deaths). ATLL prevalence and incidence in these patients were 3.0% and 3.81 per 1,000 person-y, respectively. To identify patients at a high risk of developing ATLL, flow cytometry, Southern blotting, and targeted sequencing data were analyzed in a separate cohort of 218 HAM/TSP patients. In 17% of the HAM/TSP patients, we identified an increase in T cells positive for cell adhesion molecule 1 (CADM1), a marker for ATLL and HTLV-1-infected cells. Genomic analysis revealed that somatic mutations of HTLV-1-infected cells were seen in 90% of these cases and 11% of them had dominant clone and developed ATLL in the longitudinal observation. In this study, we were able to demonstrate the increased mortality in patients with HAM/TSP and a significant effect of ATLL on their prognosis. Having dominant clonal expansion of HTLV-1-infected cells with ATLL-associated somatic mutations may be important characteristics of patients with HAM/TSP who are at an increased risk of developing ATLL.

The IL-18, IL-12, and IFN-γ expression in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, HTLV-1 carriers, and healthy subjects.

Interleukin (IL)-12, IL-18, and interferon gamma (IFN-γ) can induce Th1-inflammatory responses in favor of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) manifestation. In this study, the gene expression and plasma levels of these cytokines were evaluated. The peripheral blood mononuclear cells (PBMCs) in 20 HAM/TSP patients, 21 asymptomatic carriers (ACs), and 21 healthy subjects (HSs) were assessed for the expression of IL-18, IL-12, and IFN-γ, using qRT-PCR. The plasma level of IL-18 and IFN-γ were measured by an ELISA method. The mean of HTLV-1 proviral load (PVL) in the HAM/TSPs was 1846.59 ± 273.25 and higher than ACs at 719.58 ± 150.72 (p = 0.001). The IL-12 was considerably expressed only in nine ACs, five HAM/TSPs, and all HSs. Furthermore, the gene expression and plasma levels of IL-18 were lower in the HTLV-1-positive group than the control group (p = 0.001 and 0.012, respectively); however, there was no significant difference between the ACs and HAM/TSPs. The IFN-γ level was higher in the HTLV-1-positive group (p < 0.001) than HSs. Although there were no correlation between plasma levels of IL-18 and IFN-γ with PVL in the ACs, a positive correlation was observed between plasma IL-18 levels and PVL (r = 0.654, p = 0.002). The highest levels of IFN-γ were observed in the HAM/TSPs which has a significant correlation with HTLV-1-HBZ (r = 0.387, p = 0.05) but not with Tax. However, no significant correlation was found between PVL and proinflammatory pattern. Apart from the IFN-γ as a lymphokine, as a host factor, and HTLV-1-HBZ, as a viral agent, the other proinflammatory monokines or HTLV-1 factors are among the less-effective agents in the maintenance of HAM/TSP.

Immunophenotypic analysis of cerebrospinal fluid reveals concurrent development of ATL in the CNS of a HAM/TSP patient.

Both adult T-cell leukemia/lymphoma (ATL) and human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) can be induced by HTLV-1, but concurrent development has been rarely reported. We present the case of a 55-year-old female who developed cranial nerve symptoms after a 20-year history of HAM/TSP. Although multiple white matter lesions were observed on brain magnetic resonance imaging, no abnormalities were seen on a systemic computed tomography scan. Quantitative flow-cytometric analysis of cell populations in the cerebrospinal fluid (CSF) revealed that most of the infiltrating cells were not inflammatory cells, but HTLV-1-infected CD4+ CADM-1+ T-cells completely lacking CD7 expression. As stepwise downregulation of CD7 is correlated with disease progression from HTLV-1 carrier to aggressive ATL, the CSF cells were classified as aggressive ATL; these cells exhibited a more progressed phenotype than those in peripheral blood (PB). HAM/TSP disease activity was estimated to be low. From these and other examinations, we made a diagnosis of acute-type ATL, which unusually developed in the central nervous system at initial onset prior to systemic progression. In ATL cases with a challenging diagnosis, immunophenotypic characterization of CSF and PB is valuable for differential diagnosis and understanding disease status.

Case Report: Cognitive Impairment without Clinical Spinal Disease May Be the First Sign of HTLV-1 Neurological Alteration.

Human t-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) is a progressive neurological disease whose diagnosis is defined by clinical manifestations and seropositivity for HTLV-1 infection. Cognitive impairment (CI) is considered to occur after spinal impairment. A 51-year-old HTLV-1-infected man classified as an asymptomatic carrier presented difficulties in listening comprehension and executive memory. He was assessed for central auditory processing (CAP), cognition (event-related auditory evoked potential [P300]), and otoneurological functions (galvanic vestibular-evoked myogenic potential [gVEMP]). Altered responses were found in CAP, P300, and gVEMP, but the neurological examination and cognitive screening were normal. After a 2-year follow-up, we disclosed a positive Babinski sign, a mild CI, worsened P300, and gVEMP latencies, and the patient reported progressive lumbar pain and difficulty running. He was, then, reclassified as HAM. The first examination, in 2016, had already shown abnormal results in P300 and gVEMP despite the HTLV-1-asymptomatic carrier status. Therefore, tests that provide subclinical measures of neurological disease progression can be useful tools for an early diagnosis and intervention in HTLV-1 patients. Electrophysiological results had worsened as well as the clinical status and the cognitive function and the progression from asymptomatic status to an HTLV-1-associated neurological disease occurred within 2 years. Thus, HTLV-1-infected individuals with complaints of CI, hearing, or otoneurological manifestations should be submitted to neuropsychological and electrophysiological tests, allowing them to be properly cared in case of HAM progression.

Real-world clinical course of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in Japan.

BACKGROUND: As human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a rare chronic neurological disease, large scale studies to collect continuous clinical data have been difficult to conduct. Therefore, the incidence of comorbidities and drug utilization data remain unknown. When conducting trials to develop new drugs in rare disease such as HAM/TSP, historical control data obtained from registry studies would be useful, as cohorts in rare disease tend to be small. Long-term follow-up of patients with a chronic disease can also be challenging. In this study, we addressed the following two goals using registry data on patients (n = 486) enrolled in the Japanese HAM/TSP patient registry "HAM-net" from 2012 to 2016: 1) to clarify the epidemiological information of HAM/TSP such as the incidence of comorbidities and drug utilization and 2) to provide the real-world data on changes in lower limb motor dysfunction. RESULTS: In HAM-net-registered patients, common comorbidities were fractures, herpes zoster, and uveitis, with incidences of 55.5, 10.4, and 6.5, respectively, per 1000 person-years. Every year, oral steroid treatment was administered in 48.2-50.7% of the HAM-net-registered patients and interferon-α treatment was used in 2.6-3.5% of patients. The median dose of oral prednisolone was low at 5.0 mg/day. The incidence of fractures and herpes zoster tended to be higher in the steroid-treated group than in the untreated group (fractures: 61.0 vs. 48.3, herpes zoster: 12.7 vs. 8.8, per 1000 person-years). The analysis of chronological change in Osame motor disability score (OMDS) indicated that the mean change in OMDS was + 0.20 [95% confidence intervals (CI): 0.14-0.25] per year in the one-year observation group (n = 346) and + 0.57 (95% CI: 0.42-0.73) over four years in the four-year observation group (n = 148). Significant deterioration of OMDS was noted in all subgroups with varying steroid use status. CONCLUSIONS: This study revealed the incidence of comorbidities and drug utilization data in patients with HAM/TSP using registry data. Furthermore, this study provided real-world data on chronological changes in lower limb motor dysfunction in patients with HAM/TSP, indicating the utility of these data as historical controls.

Hodgkin-like adult T-cell leukemia/lymphoma that developed during the follow-up of HTLV-1 associated myelopathy/tropical spastic paraparesis.

Hodgkin-like adult T-cell leukemia/lymphoma (ATLL) is a rare variant of ATLL, which represents the early neoplastic phase of ATLL that follows an indolent clinical course compared with typical ATLL. Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a neurological disorder characterized by the paralysis of lower limbs and urinary disturbance. Although these diseases are caused by HTLV-1 infection, there are no reports describing the coexistence of Hodgkin-like ATLL and HAM/TSP. Here, we report the first case of Hodgkin-like ATLL complicated by HAM/TSP. The patient was a 56-year-old man with right inguinal lymphadenopathy who had been using the neurology outpatient service for 13 years after being diagnosed with HAM/TSP. He was unable to receive intensive chemotherapy or allogeneic stem cell transplantation due to a poor performance status, but his condition was stable for approximately two years.

Current approaches for detection of human T-lymphotropic virus Type 1: A systematic review.

BACKGROUND: Human T-lymphotropic virus Type 1 (HTLV-1) is a retrovirus that is endemic in some regions of the world. It is known to cause several diseases like adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Serology and molecular methods have been used to detect this virus. Of these, enzyme-linked immunosorbent assay (ELISA) is used as a primary screening method and this is usually followed by western blotting (WB) and polymerase chain reaction (PCR) methods as confirmatory tests. We conducted a systematic review of the different techniques used in the diagnosis of HTLV-1 infection. MATERIALS AND METHODS: Our search was limited to original papers in the English language from 2010 to 2018 using several databases including Pubmed, Scopus, Google Scholar, Iranmedex, and Scientific Information Database. A manual search of references provided in the included papers was also performed. RESULTS: Of 101 electronically searched citations, 43 met the inclusion criteria. ELISA is commonly used for qualitative and screening detection, and WB and PCR techniques are used to confirm infection. CONCLUSION: Among all the reported methods for detection of HTLV-1, only serological and molecular tests are used as the most common technical assays for HTLV-1. The ELISA assay, without a confirmatory test, has several limitations and affect the accuracy of the results. Owing to the prevalence of HTLV-1 and limitations of the current detection methods, further evaluation of the accuracy of these methods is needed. There are new opportunities for applying novel technological advances in microfluidics, biosensors, and lab-on-a-chip systems to perform HTLV-1 diagnostics.