Long-term safety and efficacy of mogamulizumab (anti-CCR4) for treating virus-associated myelopathy.

Some carriers of human T-cell leukaemia virus type 1 (HTLV-1), a retrovirus that primarily infects CD4+ T cells and causes lifelong infection, develop HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Current treatments for HAM/TSP are insufficient with problematic long-term side effects. This study evaluated the long-term safety and efficacy of the anti-CCR4 antibody mogamulizumab in patients with HAM/TSP over a 4-year period. We conducted an open-label, extended long-term study (UMIN trial number: UMIN000019942) of a phase 1-2a trial with mogamulizumab for HAM/TSP (UMIN000012655). The study participants were patients with corticosteroid-resistant HAM/TSP who could walk 10 m with or without assistive tools. Mogamulizumab was administered at 0.01, 0.03, 0.1 or 0.3 mg/kg at intervals of ≥8 weeks (0.01 and 0.03 mg/kg) or ≥12 weeks (0.1 and 0.3 mg/kg). HTLV-1 proviral load, CSF inflammatory markers and clinical symptoms were summarized by descriptive statistics. Missing observations were imputed using the last-observation-carried-forward method. As a post hoc analysis, we evaluated the therapeutic effect of mogamulizumab on gait function by comparing it with contemporary control data from a HAM/TSP patient registry. Of the 21 participants in the phase 1-2a, 18 (86%) enrolled in the long-term study and 15 (71%) continued repeated doses of mogamulizumab for 4 years. The median dose was 0.1 mg/kg after 4 years. Seventeen of 21 participants (81%) experienced grade 1-2 skin-related adverse events. Observed grade 3 drug-related adverse effects included three cases of lymphopenia and one case each of microscopic polyangiitis, elevated levels of aspartate aminotransferase, and neutropenia. Four of 21 participants (19%) developed neutralizing antibodies. After 4 years, the peripheral blood proviral load and the number of infected cells in CSF decreased by 60.7% and 66.3%, respectively. Neopterin and CXCL10 CSF concentrations decreased by 37.0% and 31.0%, respectively. Among the 18 participants, spasticity and Osame Motor Disability Score (OMDS) improved in 17 (94%) and four (22%), respectively. However, 10 m walking time worsened by 7.3% on average. Comparison with the contemporary control group demonstrated that mogamulizumab inhibited OMDS progression (P = 0.02). The results of the study suggest that mogamulizumab has long-term safety and inhibitory effects on lower limb motor disability progression in corticosteroid-treated patients with HAM/TSP. This will provide a basis for the application of mogamulizumab in HAM/TSP treatment.

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.

Hrd1 suppresses Nrf2-mediated cellular protection during liver cirrhosis.

Increased endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) are the salient features of end-stage liver diseases. Using liver tissues from liver cirrhosis patients, we observed up-regulation of the XBP1-Hrd1 arm of the ER stress response pathway and down-regulation of the Nrf2-mediated antioxidant response pathway. We further confirmed this negative regulation of Nrf2 by Hrd1 using Hrd1 conditional knockout mice. Down-regulation of Nrf2 was a surprising result, since the high levels of ROS should have inactivated Keap1, the primary ubiquitin ligase regulating Nrf2 levels. Here, we identified Hrd1 as a novel E3 ubiquitin ligase responsible for compromised Nrf2 response during liver cirrhosis. In cirrhotic livers, activation of the XBP1-Hrd1 arm of ER stress transcriptionally up-regulated Hrd1, resulting in enhanced Nrf2 ubiquitylation and degradation and attenuation of the Nrf2 signaling pathway. Our study reveals not only the convergence of ER and oxidative stress response pathways but also the pathological importance of this cross-talk in liver cirrhosis. Finally, we showed the therapeutic importance of targeting Hrd1, rather than Keap1, to prevent Nrf2 loss and suppress liver cirrhosis.

Mogamulizumab (Anti-CCR4) in HTLV-1-Associated Myelopathy.

BACKGROUND: Human T-lymphotropic virus type 1 (HTLV-1) causes the debilitating neuroinflammatory disease HTLV-1-associated myelopathy-tropical spastic paraparesis (HAM-TSP) as well as adult T-cell leukemia-lymphoma (ATLL). In patients with HAM-TSP, HTLV-1 infects mainly CCR4+ T cells and induces functional changes, ultimately causing chronic spinal cord inflammation. We evaluated mogamulizumab, a humanized anti-CCR4 monoclonal antibody that targets infected cells, in patients with HAM-TSP. METHODS: In this uncontrolled, phase 1-2a study, we assessed the safety, pharmacokinetics, and efficacy of mogamulizumab in patients with glucocorticoid-refractory HAM-TSP. In the phase 1 dose-escalation study, 21 patients received a single infusion of mogamulizumab (at doses of 0.003 mg per kilogram of body weight, 0.01 mg per kilogram, 0.03 mg per kilogram, 0.1 mg per kilogram, or 0.3 mg per kilogram) and were observed for 85 days. Of those patients, 19 continued on to the phase 2a study and received infusions, over a period of 24 weeks, of 0.003 mg per kilogram, 0.01 mg per kilogram, or 0.03 mg per kilogram at 8-week intervals or infusions of 0.1 mg per kilogram or 0.3 mg per kilogram at 12-week intervals. RESULTS: The side effects of mogamulizumab did not limit administration up to the maximum dose (0.3 mg per kilogram). The most frequent side effects were grade 1 or 2 rash (in 48% of the patients) and lymphopenia and leukopenia (each in 33%). The dose-dependent reduction in the proviral load in peripheral-blood mononuclear cells (decrease by day 15 of 64.9%; 95% confidence interval [CI], 51.7 to 78.1) and inflammatory markers in cerebrospinal fluid (decrease by day 29 of 37.3% [95% CI, 24.8 to 49.8] in the CXCL10 level and of 21.0% [95% CI, 10.7 to 31.4] in the neopterin level) was maintained with additional infusions throughout the phase 2a study. A reduction in spasticity was noted in 79% of the patients and a decrease in motor disability in 32%. CONCLUSIONS: Mogamulizumab decreased the number of HTLV-1-infected cells and the levels of inflammatory markers. Rash was the chief side effect. The effect of mogamulizumab on clinical HAM-TSP needs to be clarified in future studies. (Funded by the Japan Agency for Medical Research and Development and the Ministry of Health, Labor, and Welfare; UMIN trial number, UMIN000012655 .).

The E3 ligase synoviolin controls body weight and mitochondrial biogenesis through negative regulation of PGC-1ß.

Obesity is a major global public health problem, and understanding its pathogenesis is critical for identifying a cure. In this study, a gene knockout strategy was used in post-neonatal mice to delete synoviolin (Syvn)1/Hrd1/Der3, an ER-resident E3 ubiquitin ligase with known roles in homeostasis maintenance. Syvn1 deficiency resulted in weight loss and lower accumulation of white adipose tissue in otherwise wild-type animals as well as in genetically obese (ob/ob and db/db) and adipose tissue-specific knockout mice as compared to control animals. SYVN1 interacted with and ubiquitinated the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1ß, and Syvn1 mutants showed upregulation of PGC-1ß target genes and increase in mitochondrion number, respiration, and basal energy expenditure in adipose tissue relative to control animals. Moreover, the selective SYVN1 inhibitor LS-102 abolished the negative regulation of PGC-1ß by SYVN1 and prevented weight gain in mice. Thus, SYVN1 is a novel post-translational regulator of PGC-1ß and a potential therapeutic target in obesity treatment.

Mogamulizumab, an anti-CCR4 antibody, targets human T-lymphotropic virus type 1-infected CD8+ and CD4+ T cells to treat associated myelopathy.

BACKGROUND: Human T-lymphotropic virus type 1 (HTLV-1) can cause chronic spinal cord inflammation, known as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Since CD4(+)CCR4(+) T cells are the main HTLV-1 reservoir, we evaluated the defucosylated humanized anti-CCR4 antibody mogamulizumab as a treatment for HAM/TSP. METHODS: We assessed the effects of mogamulizumab on peripheral blood mononuclear cells from 11 patients with HAM/TSP. We also studied how CD8(+) T cells, namely CD8(+) CCR4(+) T cells and cytotoxic T lymphocytes, are involved in HTLV-1 infection and HAM/TSP pathogenesis and how they would be affected by mogamulizumab. RESULTS: Mogamulizumab effectively reduced the HTLV-1 proviral load (56.4% mean reduction at a minimum effective concentration of 0.01 µg/mL), spontaneous proliferation, and production of proinflammatory cytokines, including interferon γ (IFN-γ). Like CD4(+)CCR4(+) T cells, CD8(+)CCR4(+) T cells from patients with HAM/TSP exhibited high proviral loads and spontaneous IFN-γ production, unlike their CCR4(-) counterparts. CD8(+)CCR4(+) T cells from patients with HAM/TSP contained more IFN-γ-expressing cells and fewer interleukin 4-expressing cells than those from healthy donors. Notably, Tax-specific cytotoxic T lymphocytes that may help control the HTLV-1 infection were overwhelmingly CCR4(-). CONCLUSIONS: We determined that CD8(+)CCR4(+) T cells and CD4(+)CCR4(+) T cells are prime therapeutic targets for treating HAM/TSP and propose mogamulizumab as a new treatment.

Positive feedback loop via astrocytes causes chronic inflammation in virus-associated myelopathy.

Human T-lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a rare neurodegenerative disease characterized by chronic inflammation in the spinal cord. We hypothesized that a positive feedback loop driven by chemokines may be responsible for the chronic inflammation in HAM/TSP. We aimed to determine the identity of these chemokines, where they are produced, and how they drive chronic inflammation in HAM/TSP. We found that patients with HAM/TSP have extraordinarily high levels of the chemokine CXCL10 (also known as IP-10) and an abundance of cells expressing the CXCL10-binding receptor CXCR3 in the cerebrospinal fluid. Histological analysis revealed that astrocytes are the main producers of CXCL10 in the spinal cords of patients with HAM/TSP. Co-culture of human astrocytoma cells with CD4+ T cells from patients with HAM/TSP revealed that astrocytes produce CXCL10 in response to IFN-γ secreted by CD4+ T cells. Chemotaxis assays results suggest that CXCL10 induces migration of peripheral blood mononuclear cells to the central nervous system and that anti-CXCL10 neutralizing antibody can disrupt this migration. In short, we inferred that human T-lymphotropic virus type 1-infected cells in the central nervous system produce IFN-γ that induces astrocytes to secrete CXCL10, which recruits more infected cells to the area via CXCR3, constituting a T helper type 1-centric positive feedback loop that results in chronic inflammation.

Diagnostic Value of Anti-HTLV-1-Antibody Quantification in Cerebrospinal Fluid for HTLV-1-Associated Myelopathy.

The diagnostic accuracy of cerebrospinal fluid (CSF) anti-human T-cell leukemia virus type I (HTLV-1) antibody testing for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM) remains unclear. Therefore, we measured the anti-HTLV-1 antibody levels in CSF using various test kits, evaluated the stability of CSF antibodies, and performed a correlation analysis using the particle agglutination (PA) method, as well as a receiver operating characteristic (ROC) analysis between patients with HAM and carriers. The CSF anti-HTLV-1 antibody levels were influenced by freeze-thaw cycles but remained stable when the CSF was refrigerated at 4 °C for up to 48 h. Measurements from 92 patients (69 patients with HAM and 23 carriers) demonstrated a strong correlation (r > 0.9) with the PA method across all six quantifiable test kits. All six test kits, along with CSF neopterin and CXCL10, exhibited areas under the ROC curve greater than 0.9, indicating a high diagnostic performance for HAM. Among these, five test kits, Lumipulse and Lumipulse Presto HTLV-I/II, HISCL-UD (a kit under development), HTLV-Abbott, and Elecsys HTLV-I/II, established a cutoff with 100% sensitivity and maximum specificity, achieving a sensitivity of 100% and a specificity ranging from 43.5% to 56.5%. This cutoff value, in combination with clinical findings, will aid in the accurate diagnosis of HAM.

Large-Scale Whole-Genome Analysis of HTLV-1-Associated Myelopathy Identified Hereditary Spastic Paraplegias.

Objectives: Distinguishing human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy from hereditary spastic paraplegia in patients infected with HTLV-1 is challenging due to overlapping clinical symptoms. The aim of this study was to explore the possibility that hereditary spastic paraplegia is inherently present in patients diagnosed with HTLV-1-associated myelopathy. Methods: We performed whole-genome sequencing on 315 unrelated patients registered in the HTLV-1-Associated Myelopathy patient registry "HAM-net," from 2013 to 2022 in Japan. CSF inflammatory biomarkers, including CXCL10, were measured. Results: We identified 5 patients with pathogenic variants in the genes RTN2, SPAST, VCP, and UBAP1, which are the known causes of hereditary spastic paraplegia. These patients had no family history of hereditary spastic paraplegia. The levels of CSF inflammatory biomarkers were lower than expected in these patients, compared with disease severity. Discussion: Genetic analysis is useful for the differentiation of hereditary spastic paraplegia patients from HTLV-1-associated myelopathy patients, especially for the patients with low levels of CSF inflammatory markers. Here we report the presence of hereditary spinal cord diseases in patients diagnosed with HTLV-1-associated myelopathy and provides evidence that genetic analysis would be helpful in the diagnostic workflow.

The Japanese version of the modified ACR preliminary diagnostic criteria for fibromyalgia and the fibromyalgia symptom scale: reliability and validity.

PURPOSE: The aim of this study is to investigate the reliability and validity of the Japanese version of the modified American College of Rheumatology (ACR) Preliminary Diagnostic Criteria for Fibromyalgia (mACR 2010-J) and the Fibromyalgia Symptom Scale (mFS-J). METHODS: According to the ACR 1990 classification criteria, patients with chronic pain were divided into the fibromyalgia group and nonfibromyalgia group (rheumatoid arthritis and osteoarthritis). Patients in both groups were assessed using mACR 2010-J and mFS-J. RESULTS: 294 of 462 (64 %) patients in the fibromyalgia group met mACR 2010-J, whereas 4 % (9/231) of the nonfibromyalgia group did, with sensitivity of 64 %, specificity of 96 %, positive predictive value of 97 %, negative predictive value of 56 %, and positive likelihood ratio of 16.3. Mean total scores on mFS-J significantly differentiated the fibromyalgia from the nonfibromyalgia group. According to the value of the Youden index, the best cutoff score for the mFS-J was 9/10. CONCLUSION: Our findings indicate that mACR 2010-J as a positive test and mFS-J as a quantification scale might be suitable for assessing fibromyalgia among Japanese chronic pain populations.

[National Questionnaire Survey on the Actual Use and Content Evaluation of the human T-cell leukemia virus type I (HTLV-1) -associated Myelopathy (HAM) Practice Guidelines 2019].

It is not enough to just create medical practice guidelines; they are also required to be implemented into practice. Therefore, we surveyed specialists to determine the extent of the dissemination of the "HAM Practice Guidelines 2019," to quantify gaps, identify challenges, and understand needs in daily practice. The survey also revealed that the 25% of the specialists were unaware of the tests required for confirming human T-cell leukemia virus type I (HTLV-1) infection. Additionally, they had insufficient knowledge of the HTLV-1 infection. About 90.7% of the specialists agreed with the policy of determining treatment intensity based on disease activity. However, the implementation rate of cerebrospinal fluid marker measurement, which is useful for this assessment, was as low as 27%. Hence, it is important to use the findings of this study to further promote awareness about this issue.

EZH1/2 dual inhibitors suppress HTLV-1-infected cell proliferation and hyperimmune response in HTLV-1-associated myelopathy.

Background: Human T-cell leukemia virus type 1 (HTLV-1) causes HTLV-1-associated myelopathy (HAM), adult T-cell leukemia/lymphoma (ATL), HTLV-1-associated uveitis, and pulmonary diseases. Although both HAM and ATL show proliferation of infected cells, their pathogeneses are quite different. In particular, the pathogenesis of HAM is characterized by hyperimmune responses to HTLV-1-infected cells. Recently, we demonstrated the overexpression of histone methyltransferase EZH2 in ATL cells and the cytotoxic effects of EZH2 inhibitors and EZH1/2 dual inhibitors on these cells. However, these phenomena have never been studied in HAM. Furthermore, what effect these agents have on the hyperimmune response seen in HAM is completely unknown. Methods: In this study, we investigated histone methyltransferase expression levels in infected cell populations (CD4+ and CD4+CCR4+ cells) from patients with HAM using microarray and RT-qPCR analyses. Next, using an assay system that utilizes the spontaneous proliferation characteristic of peripheral blood mononuclear cells derived from patients with HAM (HAM-PBMCs), we investigated the effects of EZH2 selective inhibitors (GSK126 and tazemetostat) and EZH1/2 dual inhibitors (OR-S1 and valemetostat, also known as DS-3201), particularly on cell proliferation rate, cytokine production, and HTLV-1 proviral load. We also examined the effect of EZH1/2 inhibitors on the proliferation of HTLV-1-infected cell lines (HCT-4 and HCT-5) derived from patients with HAM. Results: We found elevated expression of EZH2 in CD4+ and CD4+CCR4+ cells from patients with HAM. EZH2 selective inhibitors and EZH1/2 inhibitors significantly inhibited spontaneous proliferation of HAM-PBMC in a concentration-dependent manner. The effect was greater with EZH1/2 inhibitors. EZH1/2 inhibitors also reduced the frequencies of Ki67+ CD4+ T cells and Ki67+ CD8+ T cells. Furthermore, they reduced HTLV-1 proviral loads and increased IL-10 levels in culture supernatants but did not alter IFN-γ and TNF-α levels. These agents also caused a concentration-dependent inhibition of the proliferation of HTLV-1-infected cell lines derived from patients with HAM and increased annexin-V(+)7-aminoactinomycin D(-) early apoptotic cells. Conclusion: This study showed that EZH1/2 inhibitors suppress HTLV-1-infected cell proliferation through apoptosis and the hyperimmune response in HAM. This indicates that EZH1/2 inhibitors may be effective in treating HAM.

Overexpression of SPACIA1/SAAL1, a newly identified gene that is involved in synoviocyte proliferation, accelerates the progression of synovitis in mice and humans.

OBJECTIVE: To identify novel genes associated with dysregulated proliferation of activated synovial fibroblasts, which are involved in arthritic joint destruction. METHODS: We performed transcriptome analysis to identify genes that were up-regulated in the foot joints of mice with collagen-induced arthritis (CIA). The effect of candidate genes on proliferation of synovial fibroblasts was screened using antisense oligodeoxynucleotides and small interfering RNAs (siRNAs). We characterized the expression and function of a novel gene, synoviocyte proliferation-associated in collagen-induced arthritis 1 (SPACIA1)/serum amyloid A-like 1 (SAAL1) using antibodies and siRNA and established transgenic mice to examine the effect of SPACIA1/SAAL1 overexpression in CIA. RESULTS: Human and mouse SPACIA1/SAAL1 encoded 474 amino acid proteins that shared 80% homology. SPACIA1/SAAL1 was primarily expressed in the nucleus of rheumatoid arthritis (RA) synovial fibroblasts and was highly expressed in the hyperplastic lining of inflamed synovium. In addition, its expression level in RA- or osteoarthritis (OA)-affected synovial tissue was positively correlated with the thickness of the synovial lining. Furthermore, SPACIA1/SAAL1 siRNA inhibited the proliferation of synovial fibroblasts, especially tumor necrosis factor α-induced synovial fibroblasts, by blocking entry into the S phase without inducing apoptosis. Finally, transgenic mice overexpressing SPACIA1/SAAL1 exhibited early onset and rapid progression of CIA. CONCLUSION: These results suggest that SPACIA1/SAAL1 is necessary for abnormal proliferation of synovial fibroblasts and its overexpression is associated with the progression of synovitis in mice and humans. Thus, therapy targeting SPACIA1/SAAL1 might have potential as an inhibitor of synovial proliferation in RA and/or OA.

The Japanese version of the 2010 American College of Rheumatology Preliminary Diagnostic Criteria for Fibromyalgia and the Fibromyalgia Symptom Scale: reliability and validity.

The aim of this study was to investigate the reliability and the validity of the Japanese version of the 2010 American College of Rheumatology Preliminary Diagnostic Criteria for Fibromyalgia (ACR 2010-J), and its quantification scale, the Fibromyalgia Symptom Scale (FS-J). In this study, we divided patients with chronic pain without psychiatric disorders other than depression into two groups according to the 1990 ACR Diagnostic Criteria for Fibromyalgia, a fibromyalgia group and a non-fibromyalgia group (rheumatoid arthritis, osteoarthritis, and gout). Patients in both groups were assessed using the ACR 2010-J and FS-J. Seventy-seven of 94 (82%) patients in the fibromyalgia group met the ACR 2010-J, whereas 9% (4/43) of the non-fibromyalgia group did so, with a sensitivity of 82%, specificity of 91%, positive predictive value of 95%, negative predictive value of 70%, and positive likelihood ratio of 8.8. Mean total scores on the FS-J significantly differentiated the fibromyalgia from the non-fibromyalgia group. The scale had high inter-rater reliability and high internal consistency. With a cutoff score of 10, the positive likelihood ratio was 10.1. Our findings indicate that the ACR 2010-J and FS-J have high reliability and validity, and are useful for assessing fibromyalgia in Japanese populations with chronic pain. As regards the positive likelihood ratio, that of the FS-J might be suitable as a positive test.

[The current and future approaches to the treatment of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP)].

Human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus that is the causative agent of a progressive neurological disease termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP is a chronic neuroinflammatory disease characterized by spastic paraparesis, lower limb sensory disturbance and bladder/bowel dysfunction. Over the twenty-five years since the discovery of this disease, significant advancements have been made in the pathogenic mechanisms associated with HAM/TSP, however, little progress has been made in the treatment of this disorder. This review highlights the natural history of HAM/TSP, informative results of clinical trials, and discusses the current and future approaches to the treatment of HAM/TSP within the context of our understanding of the underlying pathogenic mechanisms.

Potential role of HTLV-1 Tax-specific cytotoxic t lymphocytes expressing a unique t-cell receptor to promote inflammation of the central nervous system in myelopathy associated with HTLV-1.

Human T-lymphotropic virus 1 (HTLV-1) infection causes two serious diseases: adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy (HAM). Immunological studies have revealed that HTLV-1 Tax-specific CD8+ cytotoxic T-cells (Tax-CTLs) in asymptomatic carriers (ACs) and ATL patients play an important role in the elimination of HTLV-1-infected host cells, whereas Tax-CTLs in HAM patients trigger an excessive immune response against HTLV-1-infected host cells infiltrating the central nervous system (CNS), leading to local inflammation. Our previous evaluation of HTLV-1 Tax301-309 (SFHSLHLLF)-specific Tax-CTLs (Tax301-309-CTLs) revealed that a unique T-cell receptor (TCR) containing amino acid (AA)-sequence motif PDR, was shared among HLA-A*24:02+ ACs and ATL patients and behaved as an eliminator by strong activity against HTLV-1. However, it remains unclear whether PDR+Tax301-309-CTLs also exist in HLA-A*24:02+ HAM patients and are involved in the pathogenesis of HAM. In the present study, by high-throughput TCR repertoire analysis technology, we revealed TCR repertoires of Tax301-309-CTLs in peripheral blood (PB) of HLA-A*24:02+ HAM patients were skewed, and a unique TCR-motif PDR was conserved in HAM patients (10 of 11 cases). The remaining case dominantly expressed (-DR, P-R, and PD-), which differed by one AA from PDR. Overall, TCRs with unique AA-sequence motifs PDR, or (-DR, P-R, and PD-) accounted for a total of 0.3-98.1% of Tax301-309-CTLs repertoires of HLA-A*24:02+ HAM patients. Moreover, TCR repertoire analysis of T-cells in the cerebrospinal fluid (CSF) from four HAM patients demonstrated the possibility that PDR+Tax301-309-CTLs and (-DR, P-R, and PD-)+Tax301-309-CTLs efficiently migrated and accumulated in the CSF of HAM patients fostering increased inflammation, although we observed no clear significant correlation between the frequencies of them in PB and the levels of CSF neopterin, a known disease activity biomarker of HAM. Furthermore, to better understand the potential function of PDR+Tax301-309-CTLs, we performed immune profiling by single-cell RNA-sequencing of Tax301-309-CTLs, and the result showed that PDR+Tax301-309-CTLs up-regulated the gene expression of natural killer cell marker KLRB1 (CD161), which may be associated with T-cell activation and highly cytotoxic potential of memory T-cells. These findings indicated that unique and shared PDR+Tax301-309-CTLs have a potential role in promoting local inflammation within the CNS of HAM patients.

Health-Related Quality of Life Evaluation Using the Short Form-36 in Patients With Human T-Lymphotropic Virus Type 1-Associated Myelopathy.

Background: Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) is a neuroinflammatory disease, causing various neurological symptoms, including motor, sensory, and bladder and bowel dysfunctions. This study was designed to reveal the impact of HAM and related symptoms on health-related quality of life (HRQoL). Methods: We analyzed the Short Form-36 (SF-36) and clinical data of 538 patients with HAM registered in the HAM-net, a nationwide patient registry for HAM in Japan. HRQoL was evaluated using the SF-6D (a health state utility value calculated from the SF-36) and eight SF-36 subscales. A general liner model was used to estimate the impact of major HAM-related symptoms, including gait dysfunction, sensory disturbance in the legs (pain and numbness), urinary dysfunction, and constipation, on the SF-6D and SF-36 subscale scores. Results: The mean age and disease duration were 62.0 and 16.5 years, respectively. Of the patients, 73.2% needed walking aid; 42.7 and 67.1% had leg pain and numbness, respectively; 92.1% had urinary dysfunction; and 77.9% had constipation. The mean SF-6D score was 0.565, which was significantly lower than the national average (0.674 in the 60-69 years age group; p < 0.001), exceeding the minimal important difference (0.05-0.1). All the major symptoms were significantly associated with a decrease in the SF-6D score. The SF-36 subscale scores were significantly lower than the national standard of 50 (p ≤ 0.001), except for mental health (MH). Gait dysfunction was associated with lower scores in physical functioning (PF), limitations on role functioning because of physical health, bodily pain, general health perception (GH), vitality (VT), and social functioning; however, no association was observed between gait dysfunction and limitations on role functioning because of emotional problems and MH. Meanwhile, sensory disturbance in the legs was associated with a decrease in scores in all subscales. Urinary dysfunction was associated with worse PF, GH, VT, and MH. Constipation was associated only with PF. Conclusion: HRQoL of patients with HAM was worse than that of the general population and was associated with all major symptoms. Thus, patients should be comprehensively managed to achieve better HRQoL.

Efficacy of Corticosteroid Therapy for HTLV-1-Associated Myelopathy: A Randomized Controlled Trial (HAMLET-P).

Corticosteroids are most commonly used to treat HTLV-1-associated myelopathy (HAM); however, their clinical efficacy has not been tested in randomized clinical trials. This randomized controlled trial included 8 and 30 HAM patients with rapidly and slowly progressing walking disabilities, respectively. Rapid progressors were assigned (1:1) to receive or not receive a 3-day course of intravenous methylprednisolone in addition to oral prednisolone therapy. Meanwhile, slow progressors were assigned (1:1) to receive oral prednisolone or placebo. The primary outcomes were a composite of ≥1-grade improvement in the Osame Motor Disability Score or ≥30% improvement in the 10 m walking time (10 mWT) at week 2 for rapid progressors and changes from baseline in 10 mWT at week 24 for slow progressors. In the rapid progressor trial, all four patients with but only one of four without intravenous methylprednisolone achieved the primary outcome (p = 0.14). In the slow progressor trial, the median changes in 10 mWT were -13.8% (95% CI: -20.1--7.1; p < 0.001) and -6.0% (95% CI: -12.8-1.3; p = 0.10) with prednisolone and placebo, respectively (p for between-group difference = 0.12). Whereas statistical significance was not reached for the primary endpoints, the overall data indicated the benefit of corticosteroid therapy. (Registration number: UMIN000023798, UMIN000024085).

RAISING is a high-performance method for identifying random transgene integration sites.

Both natural viral infections and therapeutic interventions using viral vectors pose significant risks of malignant transformation. Monitoring for clonal expansion of infected cells is important for detecting cancer. Here we developed a novel method of tracking clonality via the detection of transgene integration sites. RAISING (Rapid Amplification of Integration Sites without Interference by Genomic DNA contamination) is a sensitive, inexpensive alternative to established methods. Its compatibility with Sanger sequencing combined with our CLOVA (Clonality Value) software is critical for those without access to expensive high throughput sequencing. We analyzed samples from 688 individuals infected with the retrovirus HTLV-1, which causes adult T-cell leukemia/lymphoma (ATL) to model our method. We defined a clonality value identifying ATL patients with 100% sensitivity and 94.8% specificity, and our longitudinal analysis also demonstrates the usefulness of ATL risk assessment. Future studies will confirm the broad applicability of our technology, especially in the emerging gene therapy sector.