Mycophenolate mofetil for the long-term treatment of HTLV-1 associated myelopathy: A case report

Human T-cell leukemia virus type 1 (HTLV-1) can cause HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Current treatment options for HAM/TSP are limited. We present a woman with rapidly-progressive HAM/TSP with significant, sustained clinical improvement following initiation of mycophenolate mofetil (MMA). Peripheral blood mononuclear cells from the patient, her asymptomatic carrier husband and eight healthy controls were isolated. Frequencies of T-cell populations upon exposure to low and high MMA concentrations and differences in proliferation were analyzed using flow cytometry and a CSFE-proliferation assay. Characterization of T-cell function and proliferation showed higher levels of GranzymeB in HTLV-1+ donors. The improvement and stability of symptoms in this patient with HAM/TSP following MMA initiation requires further study as a potential treatment for HAM/TSP.

Mogamulizumab for Treatment of Human T-lymphotropic Virus Type 1-Associated Myelopathy/Tropical Spastic Paraparesis: A Single-Center US-based Series

BACKGROUND

Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic neurological condition characterized by progressive myelopathic symptoms including spasticity, pain, weakness, and urinary symptoms, without proven treatments. Mogamulizumab (MOG) is a monoclonal antibody that binds CCR4 and leads to the clearance of HTLV-1-infected CCR4+ cells. A phase 1-2a study in Japan evaluated MOG for the treatment of HAM/TSP and reported decreases in HTLV-1 proviral load and neuroinflammatory markers, with clinical improvement in some participants.

METHODS

We administered MOG 0.1 mg/kg every 8 weeks to individuals with HAM/TSP as a compassionate and palliative treatment. Patients who received MOG had (1) a positive peripheral HTLV-1 antibody, (2) progressive myelopathic symptoms, and (3) a diagnosis of HAM/TSP.

RESULTS

Four female patients, ages 45-68, received MOG (range, 2-6 infusions) between 1 November 2019 and 30 November 2022. Two patients with <3 years of symptoms had milder disease, with Osame scores <4. The other 2, with >7 years of symptoms, had Osame scores >5. One patient, with 6 total treatments, received dose-reduced MOG after she developed a rash at the initial dose. The 2 patients with milder baseline disease reported symptomatic improvement and saw reductions in Osame and/or modified Ashworth scale scores during follow-up. The other 2 patients showed no improvement. All 4 developed rashes after receiving MOG-a treatment-limiting event in some cases.

CONCLUSIONS

Clinical trials are needed including diverse patient populations to assess the potential role of MOG for HAM/TSP. Our findings may help inform the development of these trials.

Precise excision of HTLV-1 provirus with a designer-recombinase

The human T cell leukemia virus type 1 (HTLV-1) is a pathogenic retrovirus that persists as a provirus in the genome of infected cells and can lead to adult T cell leukemia (ATL). Worldwide, more than 10 million people are infected and approximately 5% of these individuals will develop ATL, a highly aggressive cancer that is currently incurable. In the last years, genome editing tools have emerged as promising antiviral agents. In this proof-of-concept study, we use substrate-linked directed evolution (SLiDE) to engineer Cre-derived site-specific recombinases to excise the HTLV-1 proviral genome from infected cells. We identified a conserved loxP-like sequence (loxHTLV) present in the long terminal repeats of the majority of virus isolates. After 181 cycles of SLiDE, we isolated a designer-recombinase (designated RecHTLV), which efficiently recombines the loxHTLV sequence in bacteria and human cells with high specificity. Expression of RecHTLV in human Jurkat T cells resulted in antiviral activity when challenged with an HTLV-1 infection. Moreover, expression of RecHTLV in chronically infected SP cells led to the excision of HTLV-1 proviral DNA. Our data suggest that recombinase-mediated excision of the HTLV-1 provirus represents a promising approach to reduce proviral load in HTLV-1-infected individuals, potentially preventing the development of HTLV-1-associated diseases.

A refractory human T-cell leukemia virus type 1-associated myelopathy/tropical spastic paraparesis patient with lymphoma-type adult T-cell leukemia/lymphoma: A case report and review of the literature

RATIONALE

Adult T-cell leukemia/lymphoma (ATL) and human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) are caused by HTLV-1, but the coexistence of both disorders is rare. The estimated incidence is approximately 3%.

PATIENT CONCERNS

A 54-year-old man was unable to stand up because of spastic paraparesis 1 month after the onset. He developed lymphadenopathy in the left supraclavicular fossa 5 months after the onset. The spastic paraplegia and sensory symptoms below the thoracic spinal cord level worsened.

DIAGNOSES

Both blood and cerebrospinal fluid (CSF) tests were positive for anti-HTLV-1 antibodies. The patient was diagnosed with rapidly progressive HAM/TSP. He was also diagnosed with lymphoma-type ATL by the biopsy specimen of the lymph node. CSF examination at the time of symptom exacerbation showed abnormal lymphocytes, suggesting central infiltration of the ATL in the central nervous system.

INTERVENTIONS

Methylprednisolone pulse therapy and oral prednisolone maintenance therapy were administered for rapidly progressive HAM/TSP. Intrathecal injection of methotrexate was administered for the suggested central infiltration of the ATL.

OUTCOMES

Methylprednisolone pulse therapy and intrathecal injection of methotrexate did not improve the patient's exacerbated symptoms. Five months later, clumsiness and mild muscle weakness of the fingers appeared, and magnetic resonance imaging showed swelling of the cervical spinal cord. Clonality analysis showed monoclonal proliferation only in the DNA of a lymph node lesion, but not in the CSF and peripheral blood cells.

LESSONS

This was a case of rapidly progressive HAM/TSP associated with lymphoma-type ATL that was refractory to steroids and chemotherapy. The pathogenesis was presumed to involve ATL cells in the brain and spinal cord because of the presence of abnormal lymphocytes in the CSF, but DNA analysis could not prove direct invasion. This case suggests that when we encounter cases with refractory HAM/TSP, it should be needed to suspect the presence of ATL in the background.

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.

Inhibition of ABL1 tyrosine kinase reduces HTLV-1 proviral loads in peripheral blood mononuclear cells from patients with HTLV-1-associated myelopathy/tropical spastic paraparesis

Human T-cell leukemia virus type 1 (HTLV-1) causes incurable adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Patients with HAM/TSP have increased levels of HTLV-1-infected cells compared with asymptomatic HTLV-1 carriers. However, the roles of cellular genes in HTLV-1-infected CD4+ T cells await discovery. We performed microarray analysis of CD4+ T cells from HAM/TSP patients and found that the ABL1 is an important gene in HAM/TSP. ABL1 is a known survival factor for T- and B-lymphocytes and is part of the fused gene (BCR-ABL) known to be responsible for chronic myelogenous leukemia (CML). ABL1 tyrosine kinase inhibitors (TKIs), including imatinib, nilotinib, and dasatinib, are used clinically for treating CML. To evaluate whether ABL1 is indeed important for HAM/TSP, we investigated the effect of TKIs on HTLV-1-infected cells. We developed a propidium monoazide-HTLV-1 viability quantitative PCR assay, which distinguishes DNA from live cells and dead cells. Using this method, we were able to measure the HTLV-1 proviral load (PVL) in live cells alone when peripheral blood mononuclear cells (PBMCs) from HAM/TSP cases were treated with TKIs. Treating the PBMCs with nilotinib or dasatinib induced significant reductions in PVL (21.0% and 17.5%, respectively) in live cells. Furthermore, ABL1 siRNA transfection reduced cell viability in HTLV-1-infected cell lines, but not in uninfected cell lines. A retrospective survey based on our clinical records found a rare case of HAM/TSP who also suffered from CML. The patient showed an 84.2% PVL reduction after CML treatment with imatinib. We conclude that inhibiting the ABL1 tyrosine kinase specifically reduced the PVL in PBMCs from patients with HAM/TSP, suggesting that ABL1 is an important gene for the survival of HTLV-1-infected cells and that TKIs may be potential therapeutic agents for HAM/TSP.

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 .).

Effectiveness of Daily Prednisolone to Slow Progression of Human T-Lymphotropic Virus Type 1-Associated Myelopathy/Tropical Spastic Paraparesis: A Multicenter Retrospective Cohort Study

Millions of people are infected with human T-lymphotropic virus type 1 (HTLV-1) worldwide; notable endemic areas include Brazil, the Caribbean islands, Iran, and Japan. A small number of those infected develop the progressive neurodegenerative disease HTLV-1-associated myelopathy (HAM), also known as tropical spastic paraparesis (TSP), which is characterized by chronic spinal cord inflammation and accompanying myelopathic symptoms. The corticosteroid prednisolone (PSL) is a classic treatment for HAM/TSP, yet its effectiveness remains controversial owing to insufficient and conflicting studies. We conducted a multicenter retrospective study using data collected by physicians monitoring patients with HAM/TSP at 7 hospitals throughout Japan. The Osame Motor Disability Score (OMDS) was used to evaluate 57 patients treated with low-dose PSL (mean 4.8 mg/day) versus 29 untreated patients. Roughly half of the evaluations spanned < 3 years (Short-Term) and half > 3 years (Long-Term), with a mean of 3.4 years. While the OMDS of most untreated patients remained unchanged in the Short-Term (87%) and worsened in the Long-Term (79%), most treated patients improved in the Short-Term (52%) and remained unchanged or improved in the Long-Term (68%). Overall, the mean change in OMDS per year was -0.13 in the Steroids group and +0.12 in the Untreated group (p < 0.01). This study addressed the effectiveness of PSL for HAM/TSP in 3 novel ways: 1) continuous low-dose administration; 2) comparison with an untreated group; and 3) Long-Term evaluation. These findings provide robust evidence supporting PSL maintenance therapy for HAM/TSP.

Effect of Pulsed Methylprednisolone on Pain, in Patients with HTLV-1-Associated Myelopathy

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is an immune mediated myelopathy caused by the human T-lymphotropic virus type 1 (HTLV-1). The efficacy of treatments used for patients with HAM/TSP is uncertain. The aim of this study is to document the efficacy of pulsed methylprednisolone in patients with HAM/TSP. Data from an open cohort of 26 patients with HAM/TSP was retrospectively analysed. 1g IV methylprednisolone was infused on three consecutive days. The outcomes were pain, gait, urinary frequency and nocturia, a range of inflammatory markers and HTLV-1 proviral load. Treatment was well tolerated in all but one patient. Significant improvements in pain were: observed immediately, unrelated to duration of disease and maintained for three months. Improvement in gait was only seen on Day 3 of treatment. Baseline cytokine concentrations did not correlate to baseline pain or gait impairment but a decrease in tumour necrosis factor-alpha (TNF-α) concentration after pulsed methylprednisolone was associated with improvements in both. Until compared with placebo, treatment with pulsed methylprednisolone should be offered to patients with HAM/TSP for the treatment of pain present despite regular analgesia.

[Tropical spastic paraparesis in a non tropical region]

INTRODUCTION

Human T-lymphotropic virus 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a prevalent disease in certain tropical regions endemic for HTLV-1, being a rare entity in areas such as Europe and North America.

CASE REPORTS

We report two new cases of HAM/TSP in Caucasians, native from Galicia, Spain. Serum and cerebrospinal fluid (CSF) analysis, clinical neurophysiologic studies and brain and spinal cord MRI scans were performed. Both patients presented a progressive chronic myelopathy, evolving to spastic paraparesis; one of them presenting with uveitis, prior to the onset of neurological symptoms. CSF analysis revealed mild lymphocytic pleocytosis and increased protein concentration with positive anti-HTLV-1 antibodies. Polymerase chain reaction was positive for HTLV-1. Oligoclonal bands were not detected. In one of the patients, MRI scans did not reveal abnormalities whilst in the other there was an elongated high intensity lesion at the thoracic spinal cord level, which resolved after treatment. No evidence of peripheral neuropathy was found. Corticosteroids and interferon alpha therapy was started, with moderate functional improvement. A history of unprotected sexual relationships while travelling to HTLV-1 endemic areas was revealed.

CONCLUSIONS

HTLV-1-associated uveitis may predict HAM/TSP. HAM/TSP is probably an underdiagnosed disease due to the high prevalence of asymptomatic carriers, insidious clinical presentation and low suspicion index in non-endemic regions for HTLV-1. In non-tropical countries, HAM/TSP should not only be suspected in migrants from endemic areas for HTLV-1, but also in patients from communities with a tradition of migration to tropical countries.

Triple Therapy with Prednisolone, Pegylated Interferon and Sodium Valproate Improves Clinical Outcome and Reduces Human T-Cell Leukemia Virus Type 1 (HTLV-1) Proviral Load, Tax and HBZ mRNA Expression in Patients with HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis

Considering that there is no effective treatment for human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis, this study aimed to assess the impact of triple combination therapy-interferon-α, valproic acid, and prednisolone-on clinical outcomes, main HTLV-1 viral factors, and host anti-HTLV-1 antibody response. HTLV-1 proviral load (PVL), and HBZ and Tax mRNA expression levels were measured in peripheral blood mononuclear cells of 13 patients with HTLV-1-associated myelopathy/tropical spastic paraparesis before and after treatment with 180 μg pegylated interferon once a week, 10-20 mg/kg/day sodium valproate, and 5 mg/day prednisolone for 25 weeks using a TaqMan real-time polymerase chain reaction assay. Furthermore, anti-HTLV-1 titer, Osame Motor Disability Score, Ashworth spasticity scale, and urinary symptoms (through standard questionnaire and clinical monitoring) were assessed in patients before and after the treatment. HTLV-1 PVL and HBZ expression significantly decreased after the treatment [PVL from 1443 ± 282 to 660 ± 137 copies/10(4) peripheral blood mononuclear cells (p = 0.01); and HBZ from 8.0 ± 1.5 to 3.0 ± 0.66 (p < 0.01)]. Tax mRNA expression decreased after the treatment from 2.26 ± 0.45 to 1.44 ± 0.64, but this reduction was not statistically significant (p = 0.10). Furthermore, anti-HTLV-1 titer reduced dramatically after the treatment, from 3123 ± 395 to 815 ± 239 (p < 0.01). Clinical signs and symptoms, according to Osame Motor Disability Score and Ashworth score, improved significantly (both p < 0.01). Urinary symptoms and sensory disturbances with lower back pain were reduced, though not to a statistically significant degree. Although signs and symptoms of spasticity were improved, frequent urination and urinary incontinence were not significantly affected by the triple therapy. The results provide new insight into the complicated conditions underlying HTLV-1-associated diseases.

Human T lymphotropic virus type-1-associated myelopathy manifesting shortly after living-donor renal transplantation

A 38-year-old woman experienced numbness in both lower extremities and spastic paralysis a few months after undergoing living-donor renal transplantation. The patient was negative for human T lymphotropic virus type-1 (HTLV-1) antibodies prior to the procedure; however, she was diagnosed with HTLV-1-associated myelopathy (HAM) based on positive serum and cerebrospinal fluid antibody titers after the surgery. Because the donor was also positive for HTLV-1 antibodies, the infection likely originated from the transplanted kidney. Clinical and imaging improvements were noted following the administration of interferon-α. HAM has been reported to occur after living-donor renal transplantation; however, there are no previous reports of onset within such a short period.

Human T-lymphotropic virus type-I (HTLV-I)-associated myelopathy with bulbar palsy-type amyotrophic lateral sclerosis-like symptoms

We herein report a case of Human T-lymphotropic virus type-I (HTLV-I)-associated myelopathy with bulbar palsy-type amyotrophic lateral sclerosis-like symptoms. A 52-year-old woman developed dyslalia at approximately 40 years of age, which slowly progressed. She presented with muscular atrophy and increased tendon reflexes of the extremities as well as bulbar palsy, from which motor neuron disease was suspected. Cerebrospinal fluid (CSF) testing revealed no abnormalities except for an elevated neopterin concentration at 143.17 pmol/mL (normal ≤30 pmol/mL). Her serum and CSF anti-HTLV-I antibody titers were also high. Intravenous infusions of methylprednisolone decreased the CSF neopterin concentration to 50.33 pmol/mL. Subsequent oral prednisolone therapy was effective in alleviating the symptoms.

Cyclosporine for the treatment of HLTV-1-induced HAM/TSP: an experience from a case report

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) remains a challenging disease. Treatment options are scarce, and their safety and efficacy are currently a matter of concern.We present a case report describing our experience using cyclosporine in a patient with early HAM/TSP who started with a gait disturbance at Vall d'Hebron University Hospital (Barcelona) from August 2012 to October 2013. After 62 weeks of treatment, clinical improvement was observed and proviral load diminished. No safety concerns were observed.Cyclosporine seems to be effective in new-onset HAM/TSP or in chronic HAM/TSP that develops a relapse. However, the duration and safety profile of this steroid-sparing therapy remain unknown and should be further investigated.

Tropical spastic paraparesis treated with Combivir (lamivudine-zidovudine)

Tropical spastic paraparesis (TSP) or human T-cell leukemia virus-type 1 (HTLV-I)-associated myelopathy is caused by human T-lymphotropic virus type 1. It is a slow, progressive spastic paraparesis with significant morbidity and causing profound repercussions on quality of life. No therapies have been found to persistently improve the outcome in these patients. We present a patient with HTLV-1-associated myelopathy/TSP (HAM/TSP) who was treated with Combivir (lamivudine-zidovudine, GlaxoSmithKline, London, UK). She was walker-dependent for several years but, soon after treatment with lamivudine-zidovudine, was able to walk using only a cane. The role of lamivudine-zidovudine should be investigated further in this patient population.

Cerebrospinal fluid neopterin, but not osteopontin, is a valuable biomarker for the treatment response in patients with HTLV-I-associated myelopathy

OBJECTIVE

The concentrations of neopterin and osteopontin in the cerebrospinal fluid (CSF) were measured in patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in order to evaluate their utility as biomarkers for the treatment response.

METHODS

Seven HAM/TSP patients were treated intravenously with high-dose methylprednisolone (1,000 mg/day) for 3 days. CSF samples were collected before and after the treatment. The neopterin and osteopontin concentrations were determined using high-performance liquid chromatography (HPLC) and an enzyme immunoassay, respectively. The clinical symptoms were evaluated using the Osame Motor Disability Score and the Urinary Disturbance Score.

RESULTS

Four out of the seven patients showed an improvement in motor function with the treatment, and were therefore classed as responders. The pre-treatment CSF neopterin concentration exceeded the upper limit of normal in all seven of the patients, and tended to be higher in treatment responders as compared to non-responders. The CSF neopterin concentration was reduced following treatment in all patients. The mean CSF neopterin concentration significantly (p<0.01) decreased following treatment by almost 60% (from 124.1±79.9 nmol/L to 49.2±29.8 nmol/L). The mean CSF osteopontin concentration was significantly (p<0.01) higher in the HAM/TSP patients in comparison to the 18 HTLV-1-seronegative patients who were designated as controls (9.54±4.53 mg/L vs. 3.72±3.04 mg/L). No significant (p=0.47) reduction of the CSF osteopontin concentration was observed following the intravenous administration of high-dose methylprednisolone.

CONCLUSION

These results indicate that the CSF neopterin concentration, but not the osteopontin concentration, is a potentially valuable biomarker for monitoring the treatment response in HAM/TSP patients. Furthermore, high pre-treatment CSF neopterin concentrations may be a predictive biomarker for a response to intravenous high-dose methylprednisolone therapy.

Ciclosporin A proof of concept study in patients with active, progressive HTLV-1 associated myelopathy/tropical spastic paraparesis

Introduction

Patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) become progressively impaired, with chronic pain, immobility and bladder, bowel and sexual dysfunction. Tested antiretroviral therapies have not been effective and most patients are offered a short course of corticosteroids or interferon-α, physiotherapy and symptomatic management. Pathogenesis studies implicate activated T-lymphocytes and cytokines in tissue damage. We therefore tested the hypothesis that inhibition of T-cell activation with ciclosporin A would be safe and clinically beneficial in patients with early and/or clinically progressing HAM/TSP.

Materials and Methods

Open label, proof of concept, pilot study of 48 weeks therapy with the calcineurin antagonist, ciclosporin A (CsA), in seven patients with ‘early’ (<two years) or ‘progressive’ (>50% deterioration in timed walk during the preceding three months) HAM/TSP. Primary outcomes were incidence of clinical failure at 48 weeks and time to clinical failure.

Results

All patients completed 72 weeks study participation and five showed objective evidence of clinical improvement after 3 months treatment with CsA. Two patients exhibited clinical failure over 6.4 person-years of follow-up to week 48. One patient had a >2 point deterioration in IPEC (Insituto de Pesquisa Clinica Evandro Chagas) disability score at weeks 8 and 12, and then stopped treatment. The other stopped treatment at week 4 because of headache and tremor and deterioration in timed walk, which occurred at week 45. Overall pain, mobility, spasticity and bladder function improved by 48 weeks. Two patients recommenced CsA during follow-up due to relapse.

Conclusions

These data provide initial evidence that treatment with CsA is safe and may partially reverse the clinical deterioration seen in patients with early/progressive HAM/TSP. This trial supports further investigation of this agent's safety and effectiveness in larger, randomised controlled studies in carefully selected patients with disease progression.

HTLV-1 is a retrovirus transmitted through body fluids that is commonly seen in the West Indies, South America and Southern Japan but rarely in the UK. Although most patients remain healthy carriers, HTLV-1 causes serious conditions such as adult T cell leukaemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). The infection which is life-long cannot be eradicated and treatments for the associated diseases are limited. We report the encouraging findings of the first UK Medical Research Council funded treatment study for patients with early and/or deteriorating HAM/TSP. Treatment with ciclosporin A, a drug commonly used to dampen the immune system in transplant patients, was investigated. Symptoms and signs of disease, particularly low back pain and muscle stiffness, improved by week 24 and in some patients this improvement persisted after the 48 weeks of treatment, at least to the end of the study at week 72. Most striking was the finding that the amount of HTLV-1 in the fluid around the spinal cord, called cerebrospinal fluid, was reduced during treatment. These findings justify the further study of ciclosporin A in patients with HAM/TSP.

Fulminant myelopathy following neurogenic proximal weakness associated with human T-cell lymphotropic virus type I infection

We report a patient with human T-cell lymphotropic virus type I (HTLV-I) infection, who presented with proximal extremity neurogenic muscular weakness followed by fulminant myelopathy, but with no upper motor symptoms. The symptoms were inconsistent with the World Health Organization or El Escorial criteria for HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) or amyotrophic lateral sclerosis (ALS). This case indicates that fulminant myelopathy without upper motor neuronal symptoms may occur long after the onset of HTLV-I-associated neurogenic proximal muscular weakness. Additionally, we report that treatment with high-dose steroid pulse therapy partially improves symptoms of lightning pain and sensory disturbance.

[Case report of HTLV-1 associated myelopathy (HAM) manifested after renal transplantation]

We report a 51-year-old man with human T lymphotropic virus type-1 (HTLV-1) associated myelopathy (HAM) manifested 10 months after renal transplantation. He had progressive spastic paralysis and neurogenic bladder for 10 years. HTLV-1 antibody are positive both serum and cerebral spinal fluid (CSF). Althoght HTLV-1 was not examined in the donor, it was suspected that the patient was infected by renal transplantation. After treatment of interferon-alpha (IFN-alpha), his motor function had improved and neopterin in CSF was decreased from 158 pmol/ml to 89 pmol/ml. This is a rare case of HAM after living renal transplantation. Cyclosporin and methylpredonisolone are used as immunosuppressants for preventing graft rejection. Time for developing HAM after renal transplantation was shorter than patients after cadaveric renal transplantation. More investigations are needed to clarify the mechanisms in the development of HAM associated with renal transplantation.

Therapeutic strategies in HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP)

Human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is chronic progressive myelopathy characterized by bilateral pyramidal tracts involvement with sphincteric disturbances. HTLV-I infects approximately 10-20 million people worldwide. There are large endemic areas in southern Japan, the Caribbean, Central and South America, the Middle East, Melanesia, and equatorial regions of Africa. Since the primary neuropathological feature of HAM/TSP is chronic inflammation caused by HTLV-I infection in the spinal cord, various treatments focusing on immunomodulatory or anti-viral effects were performed for HAM/TSP patients until now. However, there are still many of problems, such as insufficient effects, side effects and expensive costs in long-term treatments, etc., in these treatments. Therefore, an ideal therapeutic strategy against HAM/TSP is still not established yet. Although only a small proportion of HTLV-I-infected individuals develops HAM/TSP, neurological symptoms are certainly progressive once myelopathy develops, leading to deterioration of the quality of life. Therefore, we now need the therapeutic regimens to protect the development, or be able to commence the treatments as soon as possible after the development safely and inexpensively even in long-term course or lifelong course of treatment. As HTLV-I-infected CD4(+) T cells are the first responders in the immunopathogenesis of HAM/TSP, the ideal treatment is the elimination of HTLV-I-infected cells from the peripheral blood. In this article, we will review the therapeutic strategies against HAM/TSP up to now and will introduce our new therapeutic approach focusing on the targeting of HTLV-I-infected cells in HAM/TSP patients.

Disulfide-mediated apoptosis of human T-lymphotrophc virus type-I (HTLV-I)-infected cells in patients with HTLV-I-associated myelopathy/tropical spastic paraparesis

BACKGROUND

This study was conducted to construct a basis for a therapeutic strategy against human T-lymphotropic virus type-I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) using a compound that contained a disulfide moiety, prosultiamine, which is a homologue of allithiamine originally synthesized by allicin and thiamine-thiol, for the targeting of HTLV-I-infected cells.

METHODS

First, we analysed the apoptotic pathway in allicin or prosultiamine treatment against an HTLV-I-infected T-cell line (HCT-1), derived from an HAM/TSP patient, by flow cytometry and western blot. Second, we evaluated the effect of targeting HTLV-I-infected cells in a prosultiamine in vitro treatment and in a clinical trial in HAM/TSP patients by quantitative PCR analysis of HTLV-I proviral load.

RESULTS

Prosultiamine, like allicin, induced caspase-dependent apoptosis against HCT-1 cells. The fact that the loss of mitochondrial membrane potential was recovered in z-VAD-fmk-pretreated HCT-1 cells with prosultiamine treatment suggested that prosultiamine can induce caspase-dependent apoptosis through the mitochondrial pathway. On the basis of data showing that prosultiamine in vitro treatment against peripheral blood CD4(+) T-cells of HAM/TSP patients induced a significant decrease of HTLV-I proviral copy numbers by apoptosis of HTLV-I-infected cells, we treated six HAM/TSP patients with intravenous administration of prosultiamine for 14 days. As a result of this treatment, the copy numbers of HTLV-I provirus in peripheral blood decreased to approximately 30-50% of their pretreatment levels with some clinical benefits in all patients.

CONCLUSIONS

Our results suggest that prosultiamine has the potential to be a new therapeutic tool that targets HTLV-I-infected cells in HAM/TSP.

Anti-Tac (daclizumab, Zenapax) in the treatment of leukemia, autoimmune diseases, and in the prevention of allograft rejection: a 25-year personal odyssey

Twenty-five years ago, we reported the production of the monoclonal antibody, anti-Tac that identifies the IL-2 receptor alpha subunit and blocks the interaction of IL-2 with this growth factor receptor. In 1997, daclizumab (Zenapax), the humanized form of this antibody, was approved by the FDA for use in the prevention of renal allograft rejection. In addition, we demonstrated that daclizumab is of value in the treatment of patients with noninfectious uveitis, multiple sclerosis, and the neurological disease human T-cell lymphotropic virus I associated myelopathy/tropical spastic paraparesis (HAM/TSP). Others demonstrated therapeutic efficacy with daclizumab in patients with pure red cell aplasia, aplastic anemia, and psoriasis. Thus, translation of basic insights concerning the IL-2/IL-2 receptor system obtained using the monoclonal antibody daclizumab provided a useful strategy for the prevention of organ allograft rejection and the treatment of patients with select autoimmune diseases or T-cell leukemia/lymphoma.

Safety and efficacy of interferon-α in 167 patients with human T-cell lymphotropic virus type 1–associated myelopathy

A postmarketing surveillance study was undertaken to investigate the safety and efficacy of interferon-alpha for human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) under routine treatment conditions. A total of 273 cases from 91 medical institutions were registered into the survey. So far, 167 cases had been evaluated for safety and 152 for efficacy. The efficacy evaluation was rated based on clinical symptoms of HAM. Efficacy ratio (rate of patients assessed as "modest to markedly improved" and "mildly improved") at 4 weeks was 66.2%. Factors that significantly affected efficacy ratio at 4 weeks was initial Osame's motor disability score (OMDS) before interferon-alpha therapy and duration and stage of illness. Sustained improvement of OMDS for at least 5 months after stopping interferon-alpha was observed in 11 of 30 patients (36.7%). A total of 536 adverse drug reactions (ADRs) occurred in 146 patients, 46 of which were serious. Because some of these ADRs occurred late, it is necessary to watch out for them during long-term treatment.

Zidovudine plus lamivudine in Human T-Lymphotropic Virus type-I-associated myelopathy: a randomised trial

BACKGROUND

No therapies have been proven to persistently improve the outcome of HTLV-I-associated myelopathy. Clinical benefit has been reported with zidovudine and with lamivudine in observational studies. We therefore conducted a randomised, double blind, placebo controlled study of six months combination therapy with these nucleoside analogues in sixteen patients.

RESULTS

Primary outcomes were change in HTLV-I proviral load in PBMCs and clinical measures. Secondary endpoints were changes in T-cell subsets and markers of activation and proliferation. Six patients discontinued zidovudine. No significant changes in pain, bladder function, disability score, gait, proviral load or markers of T-cell activation or proliferation were seen between the two arms. Active therapy was associated with an unexplained decrease in CD8 and non-T lymphocyte counts.

CONCLUSION

Failure to detect clinical improvement may have been due irreversible nerve damage in these patients with a long clinical history and future studies should target patients presenting earlier. The lack of virological effect but may reflect a lack of activity of these nucleoside analogues against HTLV-I RT in vivo, inadequate intracellular concentrations of the active moiety or the contribution of new cell infection to maintaining proviral load at this stage of infection may be relatively small masking the effects of RT inhibition.

Flow cytometry evaluation of the T-cell receptor Vbeta repertoire among human T-cell lymphotropic virus type-1 (HTLV-1) infected individuals: effect of interferon alpha therapy in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP)

Human T-cell lymphotropic virus type-1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is chronic inflammatory disease of the spinal cord characterized by perivascular lymphocytic cuffing and parenchymal lymphocytic infiltration. In this study using flow cytometry, we have investigated the T-cell receptor (TCR) Vbeta repertoire of peripheral blood T lymphocytes in 8 HAM/TSP patients, 10 HTLV-1 infected healthy carriers, and 11 uninfected healthy controls to determine if there is a biased usage of TCR Vbeta. We found that TCR Vbeta7.2 was under-utilized and Vbeta12 was over-utilized in CD4+ T cells of HTLV-1 infected individuals compared with healthy uninfected controls, whereas there were no such differences in CD8+ T cells. Comparison of Vbeta repertoire changes before and after interferon-alpha (IFN-alpha) treatment for HAM/TSP revealed that one out of five patients showed dramatic decrease of specific Vbeta in CD8+ T cells. Our results suggest that dominant Vbeta subpopulations in CD4+ T cells evolved associated with chronic HTLV-1 infection, and IFN-alpha treatment for HAM/TSP does not induce a specific pattern of TCR Vbeta changes.

Interferon-beta1a therapy in human T-lymphotropic virus type I-associated neurologic disease

Human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is an immune-mediated inflammatory disorder of the central nervous system. Immune activation in the host, which results from high levels of persistent antigenic stimulation and from transactivation of host immunoregulatory genes by HTLV-I, appears important in the pathogenesis of HAM/TSP. In a single-center, open-label trial, 12 patients with HAM/TSP were treated with doses of interferon-beta1a of up to 60mug twice weekly, based on its antiviral and immunomodulatory effects. Primary end points were immunological and virological measures that are potential biomarkers for HAM/TSP. Interferon-beta1a therapy reduced the HTLV-I tax messenger RNA load and the frequency of potentially pathogenic HTLV-I-specific CD8(+) cells. The HTLV-I proviral DNA load remained unchanged. Spontaneous lymphoproliferation, a marker of T-cell activation in HAM/TSP, also was reduced. Some measures of motor function were improved, and no significant clinical progression occurred during therapy. These results indicate that interferon-beta1a may beneficially affect the immune mechanisms central to the pathogenesis of HAM/TSP.

Th1/Th2 balance and HTLV-I proviral load in HAM/TSP patients treated with interferon-alpha

We studied the immunological and virological effects of interferon-alpha (IFN-alpha) therapy in nine patients with HTLV-I-associated myelopathy (HAM/TSP). After therapy, the percentages of CCR5+ cells in CD4+ cells significantly decreased in the cerebrospinal fluid as well as blood. The therapy also significantly lowered the intracellular IFN-gamma+/interleukin-4+ T-cell ratio in blood. Those helper T-cell type 1 (Th1)-related responses tended to be higher and reduce more evidently following therapy in three patients who clinically improved. Also, all the three patients had one or more HTLV-I copies in five blood mononuclear cells. These results suggest that IFN-alpha suppresses Th1 responses in HAM/TSP and that the patients with higher Th1 immunity and proviral loads may be responders of the therapy. Larger-scale studies are needed to confirm the findings.

Decreased Human T Lymphotropic Virus Type I (HTLV‐I) Provirus Load and Alteration in T Cell Phenotype after Interferon‐α Therapy for HTLV‐I–Associated Myelopathy/Tropical Spastic Paraparesis

To analyze the mechanism by which interferon (IFN)-alpha is effective against human T cell lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), we investigated the T cell phenotype and HTLV-I provirus load in peripheral blood mononuclear cells from 25 patients with HAM/TSP that were obtained before and after administration of IFN-alpha. The frequency of memory (CD45RA(-)CD27(+)) T cells that were CD8(high+), CXCR3(+) cell populations, and HTLV-I provirus loads were significantly decreased after treatment. The proportion of memory T cells in the CD8(high+) cell population correlated well with HTLV-I provirus load, whereas the proportion of effector (CD45RA(+)CD27(-)) cells in the CD8(high+) cell population was inversely correlated with provirus load. Interestingly, the frequency of perforin expression in CD8(high+) cells was significantly decreased after treatment in patients who experienced clinical improvement, whereas patients who did not experience clinical improvement showed an increased frequency of perforin expression. Our data suggest that fluctuations in these cell subsets are associated with both the immunomodulatory effect of IFN-alpha and the observed clinical benefit of IFN-alpha treatment in patients with HAM/TSP.

Multiple clinical manifestation of HTLV1 infection in a single patient

HTLV-1 infection is endemic in the Caribbean and several publications have reported the clinical disease entities seen in this population of patients. This case report is an account of a patient admitted to Kingstown General Hospital, St Vincent and the Grenadines, who had severe infective dermatitis, tropical spastic paraparesis (TSP) and Non-Hodgkin's Lymphoma (NHL). As far as we are aware, all three diseases have not been described in a single patient.

Interferon-alpha significantly reduces cerebrospinal fluid CD4 cell subsets in HAM/TSP

We, for the first time, analyzed T cell and natural killer (NK) cell subsets in the cerebrospinal fluid (CSF) in nine patients with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) treated with interferon-alpha (IFN-alpha). The CD4/CD8 ratio in CSF was significantly lower after the therapy, which is mainly attributable to the significant reduction in CD4+ cells, especially CD25+CD4 and CD45RO+CD4 cell subsets. Meanwhile, NK, natural T and NKT cell subsets in the CSF remained unchanged. There was no CSF lymphocyte subset significantly associated with the clinical efficacy of IFN-alpha in this small-scale study, and more patients should be analyzed to ascertain the link.

Activation of HTLV-I long terminal repeat by apoptosis inducing agents: mechanism and implications for HTLV-I pathogenicity (review)

HTLV-I is the etiological agent of adult T-cell leukemia (ATL), tropical spastic paraparesis/HTLV-I associated myelopathy (TSP/HAM) and certain other clinical disorders. After infection in human the virus enters into a latent state, in which very low viral gene expression can be detected. On the other hand several major characteristics of ATL and TSP/HAM indicate that their genesis requires activation of the dormant virus. TSP/HAM is characterized by high virus expression, which accounts for most of its immunopathological manifestations, whereas the process leading to ATL is believed to be initiated by the viral Tax protein, implying that it requires, at least, a temporary activation of the latent virus. Data from our and other laboratories suggest that this activation may likely be induced by environmental or/and intrinsic apoptosis-inducing factors. Moreover, we have demonstrated a mechanistic linkage between the activation of the viral promoter and the early stage of the apoptotic cascade. However, we have also shown that Tax rescues virus-expressing T-cells from apoptotic death. This suggests that Tax protein, emerging after activation of the latent virus, can rescue the host cells of the activated virus from the ultimate apoptotic death. Since the development of both TSP/HAM and ATL seems to depend on the viral Tax protein, we describe a possible system for anti Tax gene-therapy approach based on a negative transdominant mutant Tax gene.

Mitral valve re-replacement for impaired bioprosthesis after 19 years in a patient undergoing steroid treatment

A 59-year-old man underwent closed mitral commissurotomy for mitral stenosis at the age of 19 years, and mitral valve replacement (MVR) with a Hancock standard bioprosthesis and tricuspid annuloplasty at the age of 40 years. Two years after the second operation, the patient developed human T-lymphotropic virus type-1 infection, manifesting as myelopathy/tropical spastic paraparesis, and has required steroid therapy for 17 years. He was well for 18 years after the MVR, but has recently developed severe congestive heart failure, orthopnea and enlarged liver. Doppler echocardiography showed severe transvalvular regurgitation of the prosthesis and tricuspid valve. The patient underwent re-MVR with a 27 mm St. Jude Medical prosthesis, and tricuspid annuloplasty. The surgery was well tolerated, without any significant infectious complication. Some tears and perforations were found in the leaflets of the explanted bioprosthesis, but soft X-ray analysis showed minimal calcification. Mild changes and longer durability of the bioprosthesis may be related to the long-term use of steroid therapy.

Juvenile human T lymphotropic virus type 1-associated myelopathy

We report the cases of 5 adolescents with human T lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis, acquired in all but 1 case from the mother. The first symptom in all patients was difficulty in running, which was present for many years before the final diagnosis was made. Follow-up showed an indolent progression, regardless of treatment strategy.

Selective matrix metalloproteinase inhibitor, N-biphenyl sulfonyl phenylalanine hydroxamic acid, inhibits the migration of CD4+ T lymphocytes in patients with HTLV-I-associated myelopathy

Matrix metalloproteinases (MMPs) have been reported to be involved in various inflammatory disorders. Previous studies revealed that MMP-2 and MMP-9 might play important roles in the breakdown of the blood-brain barrier (BBB) in the central nervous system (CNS) of patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). N-Biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA) selectively inhibits MMP-2, -9 and -14, but not MMP-1, -3 and -7. In the present study, we examined whether or not the selective MMP inhibitor BPHA could inhibit the heightened migrating activity of CD4+ T cells in HAM/TSP patients. The migration assay using an invasion chamber showed that migration of CD4+ T cells in HAM/TSP patients was inhibited by 25 microM BPHA. In addition, the inhibitory ratio of migrating CD4+ lymphocytes was higher in HAM patients compared to normal controls. These results suggest that the selective MMP inhibitor BPHA has therapeutic potential for HAM/TSP.

[Potentially treatable subacute forms of infection due to the HTLV-1]

INTRODUCTION

Tropical spastic paraparesis due to HTLV-I virus is diagnosed at very advanced stages, when there is spinal atrophy present and so only symptomatic treatment can be given. Early diagnosis of HTLV-I infection in unusual syndromes and the use of corticosteroids may help to slow the development of the disease.

CLINICAL CASES

We describe two Brazilian patients who developed symptoms due to HTLV-I present for less than one year: subacute myelopathy with a sensory level and an ataxic pyramidal syndrome associated with axonal neuropathy, which partly improved after treatment with corticosteroids.

RESULTS

A 50 year old woman presented with progressive paraparesis following pain, cramps, feeling that her legs had 'gone to sleep' and sphincter dysfunction over the previous eleven months. Spinal MR showed a diffuse spinal hypersignal at D2. The 60 year old man had developed an ataxic syndrome and axonal polyneuropathy over the previous ten months. In both patients the anti-HTLV antibodies in blood and CSF were positive on ELISA as later confirmed by Western-blot. Thorough biochemical study ruled out other infectious etiologies. Both patients were treated with corticosteroids (i.v. methylprednisolone and oral prednisone respectively) and their symptoms improved, particularly the joint pains, ataxia and the 'gone to sleep' sensation of the legs.

CONCLUSIONS

The ataxic syndrome and myelopathy due to HTLV-I, when these have been diagnosed early, may benefit from corticosteroid treatment and progression of the disorder be prevented. The myelitic phase of HTLV-I infection is associated with diffuse myelopathy, which was unusually seen in our first patient on spinal MR.

Effect of lamivudine on human T-cell leukemia virus type 1 (HTLV-1) DNA copy number, T-cell phenotype, and anti-tax cytotoxic T-cell frequency in patients with HTLV-1-associated myelopathy

Patients with human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) typically have a high HTLV-1 proviral load in peripheral blood mononuclear cells and abundant, activated HTLV-1-specific cytotoxic T lymphocytes (CTLs). No effective treatment for HAM/TSP has been described so far. We report a 10-fold reduction in viral DNA for five patients with HAM/TSP during treatment with the reverse transcriptase inhibitor lamivudine. In one patient with recent-onset HAM/TSP, the reduction in viral DNA was associated with a fall in the frequency of CTLs specific to two peptides in the immunodominant viral antigen Tax. The half-life of peripheral blood mononuclear cell populations was estimated from changes in viral DNA copy number, CTL frequency, reduction in CD25 expression, and the loss of dicentric chromosomes following radiation-induced damage. Each of these four different techniques indicated a cellular half-life of approximately 3 days consistent with continuous lymphocyte replication and destruction. These results indicate that viral replication through reverse transcription significantly contributes to the maintenance of HTLV-1 viral DNA load. The relative contribution of proliferation versus replication may vary between infected people.

[Tropical spastic paraparesis/HTLV-I associated myelopathy. Report of 2 cases diagnosed in Cuiabá, Mato Grosso, Brazil]

We describe two cases of tropical spastic paraparesis/HTLV-I associated myelopathy, according to the criteria of World Health Organization-1989. These are the first cases diagnosed in Cuiabá (Mato Grosso State, Brazil). One of them had a good response with the treatment with prednisone.

Relationship between the clinical efficacy of pentoxifylline treatment and elevation of serum T helper type 2 cytokine levels in patients with human T-lymphotropic virus type I-associated myelopathy

OBJECT

Previously, we reported the efficacy of pentoxifylline (PTX) treatment in human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM). Here, we clarify the relationship between the clinical efficacy of PTX treatment and elevation of T helper type 2 (Th2) cytokine levels in HAM patients.

PATIENTS AND METHODS

PTX (300 mg) was administered daily by the oral route to 12 HAM patients for 4 weeks. We assessed the relationship between the changes in neurological status (motor disability scores, the degree of spasticity on neurological examination, and the time required to walk 10 m) and the changes in serum and cerebrospinal fluid (CSF) levels of interferon-gamma (IFN-gamma) as a Th1 cytokine and interleukin-4 and -10 (IL-4 and -10) as Th2 cytokines measured by an EASIA (enzyme-amplified sensitivity immunoassay) kit.

RESULTS

PTX treatment induced incremental increases in the levels of IL-4 and IL-10 in both sera and CSF of 6 HAM patients. Clinical improvement was associated with this elevation in IL-4 and IL-10. PTX treatment also induced a decrease in IFN-gamma levels in the sera of 6 HAM patients, but this was not correlated with clinical improvement.

CONCLUSION

These results suggest that the correction of the immunological imbalance in Th1 to Th2 cytokine responses, with upregulation of IL-4 and IL-10, may account for the clinical improvement in HAM patients treated with PTX.

[HTLV-I-associated myelopathy/tropical spastic paraparesis: report of 2 cases diagnosed in Florianópolis, Santa Catarina, Brazil]

We describe two cases of tropical spastic paraparesis/HTLV-I associated myelopathy, according to the criteria of World Health Organization-1989. These are the first cases diagnosed in Florianópolis (Santa Catarina State-Brazil). One of them had a good response with the treatment with methylprednisolone.

Successful application of pentoxifylline in the treatment of HTLV-I associated myelopathy

Fifteen patients with human T-cell lymphotropic virus type-I (HTLV-I)-associated myelopathy (HAM) were treated in an uncontrolled preliminary trial by oral administration of pentoxifylline (PTX). Motor function, neurological evaluation, immunological markers and parameters were evaluated after four weeks. In 13 of the 15 patients, motor disability, especially spasticity, improved substantially. PTX suppressed spontaneous proliferation of peripheral blood mononuclear cells in 14 of the 15 patients at four weeks. No adverse effect was observed. We concluded that PTX may be a safe and beneficial agent for the treatment of HAM.

Clinical and brain bioenergetics improvement with idebenone in a patient with Leber's hereditary optic neuropathy: a clinical and 31P-MRS study

We used phosphorus magnetic resonance spectroscopy (31P-MRS) to study in vivo brain and muscle bioenergetics in a male patient with Leber's hereditary optic neuropathy (LHON) and mtDNA mutation at 11,778 bp who developed spastic paraparesis with white matter lesions on brain MR imaging. The study was performed before and during treatment with idebenone (135 mg t.i.d.) and after withdrawal. Clinical amelioration and worsening were associated with parallel changes in brain and skeletal muscle bioenergetics following the administration or withdrawal of idebenone. Reversal of paraparesis by idebenone was paralleled by normalization of 31P-MRS, serum lactate and central motor conduction. Extra-ocular neurological dysfunction in LHON may be amenable to treatment by appropriate quinones.

The effect of rolipram on the production of cytokines in HTLV-I infected cell lines and peripheral blood mononuclear cells of patients with HTLV-I-associated myelopathy (HAM)

Previous studies have reported that the levels of pro-inflammatory cytokines, such as TNF-alpha and IFN-gamma, are elevated in the serum as well as in the cerebrospinal fluid of HAM/TSP patients. To evaluate the effect of the phosphodiesterase type IV inhibitor, rolipram on cytokine production, peripheral blood mononuclear cells (PBMCs) of HAM/TSP patients or HTLV-I infected T-cell lines (HUT102, MT2) were cultured in the presence of different doses of rolipram. The amount of cytokines in the supernatants of the cultured cells was determined by ELISA for TNF-alpha, IFN-gamma and TGF-beta. Rolipram inhibited TNF-alpha production by HUT102 and PBMCs from all the HAM/TSP patients in a dose-dependent manner. The suppression of IFN-gamma varied and was weaker in some HAM/TSP patients compared to that of TNF-alpha. The concentration of TGF-beta in the culture supernatants was not influenced by rolipram. The levels of TNF-alpha mRNA determined by competitive PCR were not changed in the cultured cells in the presence of rolipram, suggesting that rolipram inhibits TNF-alpha production at the post-transcriptional level. These findings suggest the possible benefit of rolipram as a therapeutic agent for HAM/TSP patients.