Isolation of HTLV-I from cerebrospinal fluid of a patient with myelopathy

Cytolytic Recombinant Vesicular Stomatitis Viruses Expressing STLV-1 Receptor Specifically Eliminate STLV-1 Env-Expressing Cells in an HTLV-1 Surrogate Model In Vitro

Human T-cell leukemia virus type 1 (HTLV-1) causes serious and intractable diseases in some carriers after infection. The elimination of infected cells is considered important to prevent this onset, but there are currently no means by which to accomplish this. We previously developed “virotherapy”, a therapeutic method that targets and kills HTLV-1-infected cells using a cytolytic recombinant vesicular stomatitis virus (rVSV). Infection with rVSV expressing an HTLV-1 primary receptor elicits therapeutic effects on HTLV-1-infected envelope protein (Env)-expressing cells in vitro and in vivo. Simian T-cell leukemia virus type 1 (STLV-1) is closely related genetically to HTLV-1, and STLV-1-infected Japanese macaques (JMs) are considered a useful HTLV-1 surrogate, non-human primate model in vivo. Here, we performed an in vitro drug evaluation of rVSVs against STLV-1 as a preclinical study. We generated novel rVSVs encoding the STLV-1 primary receptor, simian glucose transporter 1 (JM GLUT1), with or without an AcGFP reporter gene. Our data demonstrate that these rVSVs specifically and efficiently infected/eliminated the STLV-1 Env-expressing cells in vitro. These results indicate that rVSVs carrying the STLV-1 receptor could be an excellent candidate for unique anti-STLV-1 virotherapy; therefore, such antivirals can now be applied to STLV-1-infected JMs to determine their therapeutic usefulness in vivo.

No-reflow phenomenon and comparison to the normal-flow population postprimary percutaneous coronary intervention for ST elevation myocardial infarction: case-control study (NORM PPCI)

Introduction

No-reflow (NR) phenomenon is characterised by the failure of myocardial reperfusion despite the absence of mechanical coronary obstruction. NR negatively affects patient outcomes, emphasising the importance of prediction and management. The objective was to evaluate the incidence and independent predictors of NR in patients presenting with ST-elevation myocardial infarction (STEMI).

Methods

This was a single-centre prospective case–control study. Cases were subjects who suffered NR, and the control comparators were those who did not. Clinical outcomes were documented. Salient variables relating to the patients and their presentation, history and angiographical findings were compared using one-way analysis of variance or χ² test. Multiple regression determined the independent predictors, and a risk score was established based on the β coefficient.

Results

Of 173 consecutive patients, 24 (13.9%) suffered from NR, with 46% occurring post stent implantation. Patients with NR had increased risk of in-hospital death (OR 7.0, 95% CI 1.3 to 36.7, p=0.022). From baseline variables available prior to percutaneous coronary intervention, the independent predictors of NR were increased lesion complexity, admission systolic hypertension, weight of <78 kg and history of hypertension. Continuous data were transformed into best-fit binary variables, and a risk score was defined. Significant difference was demonstrated between the risk score of patients with NR (4.1±1) compared with controls (2.6±1) (p<0.001), and the risk score was considered a good test (area under the curve=0.823). A score of ≥4 had 75% sensitivity and 76.5% specificity.

Conclusion

Patients with NR have a higher rate of mortality following STEMI. Predictors of NR include lesion complexity, systolic hypertension and low weight. Further validation of this risk model is required.

Frequent horizontal and mother-to-child transmission may contribute to high prevalence of STLV-1 infection in Japanese macaques

Background

Simian T-cell leukemia virus type 1 (STLV-1) is disseminated among various non-human primate species and is closely related to human T-cell leukemia virus type 1 (HTLV-1), the causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. Notably, the prevalence of STLV-1 infection in Japanese macaques (JMs) is estimated to be > 60%, much greater than that in other non-human primates; however, the mechanism and mode of STLV-1 transmission remain unknown. The aim of this study is to examine the epidemiological background by which STLV-1 infection is highly prevalent in JMs.

Results

The prevalence of STLV-1 in the JMs rearing in our free-range facility reached up to 64% (180/280 JMs) with variation from 55 to 77% among five independent troops. Anti-STLV-1 antibody titers (ABTs) and STLV-1 proviral loads (PVLs) were normally distributed with mean values of 4076 and 0.62%, respectively, which were mostly comparable to those of HTLV-1-infected humans. Our initial hypothesis that some of the macaques might contribute to frequent horizontal STLV-1 transmission as viral super-spreaders was unlikely because of the absence of the macaques exhibiting abnormally high PVLs but poor ABTs. Rather, ABTs and PVLs were statistically correlated (p < 0.0001), indicating that the increasing PVLs led to the greater humoral immune response. Further analyses demonstrated that the STLV-1 prevalence as determined by detection of the proviral DNA was dramatically increased with age; 11%, 31%, and 58% at 0, 1, and 2 years of age, respectively, which was generally consistent with the result of seroprevalence and suggested the frequent incidence of mother-to-child transmission. Moreover, our longitudinal follow-up study indicated that 24 of 28 seronegative JMs during the periods from 2011 to 2012 converted to seropositive (86%) 4 years later; among them, the seroconversion rates of sexually matured (4 years of age and older) macaques and immature macaques (3 years of age and younger) at the beginning of study were comparably high (80% and 89%, respectively), suggesting the frequent incidence of horizontal transmission.

Conclusions

Together with the fact that almost all of the full-adult JMs older than 9 years old were infected with STLV-1, our results of this study demonstrated for the first time that frequent horizontal and mother-to-child transmission may contribute to high prevalence of STLV-1 infection in JMs.

The pathophysiology of acute myocardial infarction and strategies of protection beyond reperfusion: a continual challenge

The incidence of ST segment elevation myocardial infarction (STEMI) has decreased over the last two decades in developed countries, but mortality from STEMI despite widespread access to reperfusion therapy is still substantial as is the development of heart failure, particularly among an expanding older population. In developing countries, the incidence of STEMI is increasing and interventional reperfusion is often not available. We here review the pathophysiology of acute myocardial infarction and reperfusion, notably the temporal and spatial evolution of ischaemic and reperfusion injury, the different modes of cell death, and the resulting coronary microvascular dysfunction. We then go on to briefly characterize the cardioprotective phenomena of ischaemic preconditioning, ischaemic postconditioning, and remote ischaemic conditioning and their underlying signal transduction pathways. We discuss in detail the attempts to translate conditioning strategies and drug therapy into the clinical setting. Most attempts have failed so far to reduce infarct size and improve clinical outcomes in STEMI patients, and we discuss potential reasons for such failure. Currently, it appears that remote ischaemic conditioning and a few drugs (atrial natriuretic peptide, exenatide, metoprolol, and esmolol) reduce infarct size, but studies with clinical outcome as primary endpoint are still underway.

Respiratory research networks in Europe and beyond: aims, achievements and aspirations for the 21st century

Healthcare-associated infection, such as intensive care unit (ICU)-related respiratory infections, remain the most frequently encountered morbidity of ICU admission, prolonging hospital stay and increasing mortality rates. The epidemiology of ICU-related respiratory infections, particularly nonventilated ICU-associated pneumonia and ventilator-associated tracheobronchitis, appears to be quite different among different countries. European countries have different prevalence, patterns and mechanism of resistance, as well as different treatments chosen by different attending physicians. The classical clinical research process in respiratory infections consists of the following loop: 1) identification of knowledge gaps; 2) systematic review and search for adequate answers; 3) generation of study hypotheses; 4) design of study protocols; 5) collection clinical data; 6) analysis and interpretation of the results; and 7) implementation of the results in clinical practice.

Pragmatic Clinical Trials in CKD: Opportunities and Challenges

Randomized controlled trials in CKD lag in number behind those of other chronic diseases, despite the high morbidity and mortality experienced by patients with kidney disease and the exorbitant costs of their health care. Observational studies of CKD frequently yield seemingly paradoxic associations of traditional risk factors with outcomes, making it difficult to extrapolate the results of trials conducted in people with normal kidney function to patients with CKD. However, many completed trials in CKD have been limited by intermediate outcomes of unclear clinical significance or narrow eligibility criteria that limit external validity, and implementation of proven therapies remains a challenge. It is therefore imperative that the nephrology community capitalize on recent interest in novel approaches to trial design, such as pragmatic clinical trials. These trials are meant to promote research within real world settings to yield clinically relevant results with greater applicability than those of traditional trials, while maintaining many advantages, such as controlling for potential sources of bias. We provide a description of pragmatic clinical trials and a discussion of advantages, disadvantages, and practical challenges inherent to this study design, in the context of specific scientific questions relevant to patients with CKD.

Ultrasonography and magnetic resonance imaging findings of rheumatoid arthritis-like arthritis in a patient with adult T-cell leukemia

A 43-year-old Japanese woman with adult T-cell leukemia (ATL) developed rheumatoid arthritis-like polyarthritis with dermatitis and skin erosion. Her rheumatoid factor and C-reactive protein results were positive. Musculoskeletal ultrasonography showed intra-articular and peritendinous power Doppler signal-positive synovitis. Plain magnetic resonance imaging showed synovitis of the above lesion and remarkable bone marrow edema/osteitis. She was diagnosed as having ATL-associated arthritis based on the invasion of ATL cells by skin biopsy at the arthritis lesion.

Coronary artery bypass grafting: Part 1--the evolution over the first 50 years

Surgical treatment for angina pectoris was first proposed in 1899. Decades of experimental surgery for coronary artery disease finally led to the introduction of coronary artery bypass grafting (CABG) in 1964. Now that we are approaching 50 years of CABG experience, it is appropriate to summarize the advancement of CABG into a procedure that is safe and efficient. This review provides a historical recapitulation of experimental surgery, the evolution of the surgical techniques and the utilization of CABG. Furthermore, data on contemporary clinical outcomes are discussed.

Reperfusion therapy of acute ischaemic stroke and acute myocardial infarction: similarities and differences

The evolution of reperfusion therapy in acute myocardial infarction and acute ischaemic stroke has many similarities: thrombolysis is superior to placebo, intra-arterial thrombolysis is not superior to intravenous (i.v.), facilitated intervention is of questionable value, and direct mechanical recanalization without thrombolysis is proven (myocardial infarction) or promising (stroke) to be superior to thrombolysis-but only when started with no or minimal delay. However, there are also substantial differences. Direct catheter-based thrombectomy in acute ischaemic stroke is more difficult than primary angioplasty (in ST-elevation myocardial infarction [STEMI]) in many ways: complex pre-intervention diagnostic workup, shorter time window for clinically effective reperfusion, need for an emergent multidisciplinary approach from the first medical contact, vessel tortuosity, vessel fragility, no evidence available about dosage and combination of peri-procedural antithrombotic drugs, risk of intracranial bleeding, unclear respective roles of thrombolysis and mechanical intervention, lower number of suitable patients, and thus longer learning curves of the staff. Thus, starting acute stroke interventional programme requires a lot of learning, discipline, and humility. Randomized trials comparing different reperfusion strategies provided similar results in acute ischaemic stroke as in STEMI. Thus, it might be expected that also a future randomized trial comparing direct (primary) catheter-based thrombectomy vs. i.v. thrombolysis could show superiority of the mechanical intervention if it would be initiated without delay. Such randomized trial is needed to define the role of mechanical intervention alone in acute stroke treatment.

The rise of cardiovascular medicine

Modern cardiology was born at the turn of the nineteenth to twentieth centuries with three great discoveries: the X ray, the sphygmomanometer, and the electrocardiograph. This was followed by cardiac catheterization, which led to coronary angiography and to percutaneous coronary intervention. The coronary care units and early reperfusion reduced the early mortality owing to acute myocardial infarction, and the discovery of coronary risk factors led to the development of Preventive Cardiology. Other major advances include several cardiac imaging techniques, the birth and development of cardiac surgery, and the control of cardiac arrhythmias. The treatment of heart failure, although greatly improved, remains a challenge. Current cardiology practice is evidence-based and global in scope. Research and practice are increasingly conducted in cardiovascular centres and institutes. It is likely that in the future, a greater emphasis will be placed on prevention, which will be enhanced by genetic information.

Primary angioplasty in acute myocardial infarction with right bundle branch block: should new onset right bundle branch block be added to future guidelines as an indication for reperfusion therapy?

AIMS

The current guidelines recommend reperfusion therapy in acute myocardial infarction (AMI) with ST-segment elevation or left bundle branch block (LBBB). Surprisingly, the right bundle branch block (RBBB) is not listed as an indication for reperfusion therapy. This study analysed patients with AMI presenting with RBBB [with or without left anterior hemiblock (LAH) or left posterior hemiblock (LPH)] and compared them with those presenting with LBBB or with other electrocardiographic (ECG) patterns. The aim was to describe angiographic patterns and primary angioplasty use in AMI patients with RBBB.

METHODS AND RESULTS

A cohort of 6742 patients with AMI admitted to eight participating hospitals was analysed. Baseline clinical characteristics, ECG patterns, coronary angiographic, and echocardiographic data were correlated with the reperfusion therapies used and with in-hospital outcomes. Right bundle branch block was present in 6.3% of AMI patients: 2.8% had RBBB alone, 3.2% had RBBB + LAH, and 0.3% had RBBB + LPH. TIMI flow 0 in the infarct-related artery was present in 51.7% of RBBB patients vs. 39.4% of LBBB patients (P = 0.023). Primary percutaneous coronary intervention (PCI) was performed in 80.1% of RBBB patients vs. 68.3% of LBBB patients (P< 0.001). In-hospital mortality of RBBB patients was similar to LBBB (14.3 vs. 13.1%, P = 0.661). Patients with new or presumably new blocks had the highest (LBBB 15.8% and RBBB 15.4%) incidence of cardiogenic shock from all ECG subgroups. Percutaneous coronary intervention was done more frequently (84.8%) in patients with new or presumably new RBBB when compared with other patients with blocks (old RBBB 66.0%, old LBBB 62.3%, new or presumably new LBBB 73.0%). In-hospital mortality was highest (18.8%) among patients presenting with new or presumably new RBBB, followed by new or presumably new LBBB (13.2%), old LBBB (10.1%), and old RBBB (6.4%). Among 35 patients with acute left main coronary artery occlusion, 26% presented with RBBB (mostly with LAH) on the admission ECG.

CONCLUSION

Acute myocardial infarction with RBBB is frequently caused by the complete occlusion of the infarct-related artery and is more frequently treated with primary PCI when compared with AMI + LBBB. In-hospital mortality of patients with AMI and RBBB is highest from all ECG presentations of AMI. Restoration of coronary flow by primary PCI may lead to resolution of the conduction delay on the discharge ECG. Right bundle branch block should strongly be considered for listing in future guidelines as a standard indication for reperfusion therapy, in the same way as LBBB.

Factors related to heart rupture in acute coronary syndromes in the Global Registry of Acute Coronary Events

AIMS

To determine the incidence and factors associated with heart rupture (HR) in acute coronary syndrome (ACS) patients.

METHODS AND RESULTS

Among 60 198 patients, 273 (0.45%) had HR (free wall rupture, n = 118; ventricular septal rupture, n = 155). Incidence was 0.9% for ST-segment elevation myocardial infarction (STEMI), 0.17% for non-STEMI, and 0.25% for unstable angina. Hospital mortality was 58 vs. 4.5% in patients without HR (P < 0.001). The incidence was lower in STEMI patients with primary percutaneous coronary intervention (PCI) than in those without (0.7 vs. 1.1%; P = 0.01), but primary PCI was not independently related to HR in adjusted analysis (P = 0.20). Independent variables associated with HR included: ST-segment elevation (STE)/left bundle branch block; ST-segment deviation; female sex; previous stroke; positive initial cardiac biomarkers; older age; higher heart rate; systolic blood pressure/30 mmHg decrease. Conversely, previous MI and the use of low-molecular-weight heparin and beta-blockers during first 24 h were identified as protective factors for HR.

CONCLUSION

The incidence of HR is low in patients with ACS, although its incidence is probably underestimated. Heart rupture occurs more frequently in ACS with STE and is associated with high hospital mortality. A number of variables are independently related to HR.

Benefits of reperfusion beyond infarct size limitation

The most critical determinant of prognosis in patients with acute myocardial infarction (MI) is infarct magnitude, which can be established within several hours of an attack. The importance of the subsequent healing process is not negligible, however. In fact, much experimental and clinical evidence suggests that late reperfusion of the infarct-related coronary artery--i.e. at times too late to salvage the myocardium within the area at risk-is beneficial for reducing left ventricular remodelling and decreasing mortality ('open artery hypothesis'). For instance, one recent study highlighted the beneficial effects of late reperfusion therapy on the infarct tissue cell dynamics following acute MI. Nonetheless, several recent large, randomized clinical trials have failed to provide evidence of such benefits, refuting the clinical efficacy of late reperfusion. In addition, they also underscore the need for revised clinical studies in which there is less heterogeneity in the timing of reperfusion and in the initial infarct size, as well as the need for sustained patency of the recanalized artery. This review focuses on the effects of late reperfusion on the pathophysiology of MI in the context of the infarct tissue dynamics and clinical outcomes. We also discuss the issues that need to be resolved to improve clinical application.

Phenotypic and genotypic comparisons of human T-cell leukemia virus type 1 reverse transcriptases from infected T-cell lines and patient samples

It is well established that cell-free infection with human T-cell leukemia virus type 1 (HTLV-1) is less efficient than that with other retroviruses, though the specific infectivities of only a limited number of HTLV-1 isolates have been quantified. Earlier work indicated that a post-entry step in the infectious cycle accounted for the poor cell-free infectivity of HTLV-1. To determine whether variations in the pol gene sequence correlated with virus infectivity, we sequenced and phenotypically tested pol genes from a variety of HTLV-1 isolates derived from primary sources, transformed cell lines, and molecular clones. The pol genes and deduced amino acid sequences from 23 proviruses were sequenced and compared with 14 previously published sequences, revealing a limited number of amino acid variations among isolates. The variations appeared to be randomly dispersed among primary isolates and proviruses from cell lines and molecular clones. In addition, there was no correlation between reverse transcriptase sequence and the disease phenotype of the original source of the virus isolate. HTLV-1 pol gene fragments encoding reverse transcriptase were amplified from a variety of isolates and were subcloned into HTLV-1 vectors for both single-cycle infection and spreading-infection assays. Vectors carrying pol genes that matched the consensus sequence had the highest titers, and those with the largest number of variations from the consensus had the lowest titers. The molecular clone from CS-1 cells had four amino acid differences from the consensus sequence and yielded infectious titers that were approximately eight times lower than those of vectors encoding a consensus reverse transcriptase.

Treatment for HTLV-I associated arthropathy: a case study and synovial tissue culture analysis

OBJECTIVE

There are few reports regarding the treatment of HTLV-I associated arthropathy (HAAP). This is a case study describing the treatment of a patient diagnosed with HAAP. We also analyzed the effects of various agents on cultured synovial tissue explants from the patient.

METHODS

Arthroscopic synovectomy of the left knee was performed. We investigated the effects of pirarubicin (THP), bestatin, betamethasone, and hyaluronic acid (HA) in synovial tissue culture to evaluate the efficacy of these medications.

RESULTS

Swelling and pain of the left knee was transiently diminished after synovectomy. However, bilateral swelling of the knees and C reactive protein (CRP) concentrations were increased. In the explant culture experiments, CD8+ cells decreased with the addition of bestatin, betamethasone, and HA. The structure of synovial cells was preserved by the addition of HA. However, the addition of THP induced fibrosis of synovial tissues, increased cells without nuclei, and diminished fascin-expressing cells.

CONCLUSION

THP inhibited, but HA preserved the structure of hypertrophic synovial cells. Scopic synovectomy effectively improved joint effusion and pain; however, the effect was transient, and additional treatment with predonisolone was required. Therefore, it is important to develop a more effective treatment for HAAP.

Do we need additional markers of myocyte necrosis: the potential value of heart fatty-acid-binding protein

Heart fatty-acid-binding protein (FABP) is a small cytosolic protein that is abundant in the heart and has low concentrations in the blood and in tissues outside the heart. It appears in the blood as early as 1.5 h after onset of symptoms of infarction, peaks around 6 h and returns to baseline values in 24 h. These features of H-FABP make it an excellent potential candidate for the detection of acute myocardial infarction (AMI). We review the strengths and weaknesses of H-FABP as a clinically applicable marker of myocyte necrosis in the context of acute coronary syndromes.

Are symptomatic endpoints acceptable in venous thromboprophylactic studies?

Chemoprophylaxis with subcutaneous low-molecular-weight heparin has been shown to reduce deep vein thrombosis detected by surrogate endpoints such as fibrinogen scanning and venography. However, there have been few trials which have assessed clinical endpoints attributed to fatal and non-fatal pulmonary embolism following surgery. As these clinical endpoints are rare, large-scale trials using vascular mortality, vascular morbidity and the incidence of haemorrhage as clinical endpoints need to be performed to assess the efficacy of chemical thromboprophylaxis. The benefit of using clinical endpoints against the risk of haemorrhage should also be evaluated.

Ischemic Heart Disease in the Elderly:A Need to Understand the Causes of High Mortality After Acute Myocardial Infarction

The short- and long-term mortality of patients greater than 75 years of age with acute myocardial infarction is still very high. These patients have been excluded from most randomized controlled trials designed to test interventions directed to improve the outcome of acute myocardial infarction. Contrary to young-old patients (65-74 years) in whom the benefit obtained with these interventions is even greater than that observed in younger patients, there is a lack of information concerning the optimal treatment of acute myocardial infarction in the oldest patients. Research specifically directed to assess the optimal reperfusion strategy and coadjuvant therapies in patients greater than 75 years old is critically important. The causes for such high mortality are still poorly understood. Several clinical observations suggest that old patients with acute myocardial infarction have specific pathophysiologic behaviors. As the knowledge of the mechanisms of disease is, in clinical practice, the basis of therapy development, clinical and basic research designed to elucidate the specific pathophysiological mechanisms and causes of the high mortality in the oldest patients with acute myocardial infarction should be regarded as a priority in geriatric cardiovascular research. (c) 2000 by CVRR, Inc.

Interactions between brain endothelial cells and human T-cell leukemia virus type 1-infected lymphocytes: mechanisms of viral entry into the central nervous system

Human T-cell leukemia virus type 1 (HTLV-1) is associated with a variety of clinical manifestations, including tropical spastic paraparesis or HTLV-1-associated myelopathy (TSP/HAM). Viral detection in the central nervous system (CNS) of TSP/HAM patients demonstrates the ability of HTLV-1 to cross the blood-brain barrier (BBB). To investigate viral entry into the CNS, rat brain capillary endothelial cells were exposed to human lymphocytes chronically infected by HTLV-1 (MT2), to lymphocytes isolated from a seropositive patient, or to a control lymphoblastoid cell line (CEM). An enhanced adhesion to and migration through brain endothelial cells in vitro was observed with HTLV-1-infected lymphocytes. HTLV-1-infected lymphocytes also induced a twofold increase in the paracellular permeability of the endothelial monolayer. These effects were associated with an increased production of tumor necrosis factor alpha by HTLV-1-infected lymphocytes in the presence of brain endothelial cells. Ultrastructural analysis showed that contact between endothelial cells and HTLV-1-infected lymphocytes resulted in a massive and rapid budding of virions from lymphocytes, followed by their internalization into vesicles by brain endothelial cells and apparent release onto the basolateral side, suggesting that viral particles may cross the BBB using the transcytotic pathway. Our study also demonstrates that cell-cell fusion occurs between HTLV-1-infected lymphocytes and brain endothelial cells, with the latter being susceptible to transient HTLV-1 infection. These aspects may help us to understand the pathogenic mechanisms associated with neurological diseases induced by HTLV-1 infection.

The open-artery hypothesis

Early reperfusion of an infarct-related coronary artery results in myocardial salvage, with subsequent improvement in left ventricular function and survival. However, late reperfusion, which occurs at a time when myocardial salvage is no longer possible, still exerts a favorable impact on left ventricular function and survival. This concept is known as the open-artery hypothesis. Possible mechanisms for this benefit include improved infarct healing, limitation of ventricular remodeling, decreased ventricular arrhythmias, and reperfusion of hibernating myocardium. Although an open infarct-related coronary artery is crucial, it has not been proven that opening an occluded coronary artery using angioplasty is beneficial. A large randomized clinical trial is clearly needed.

Detection of HTLV-I in Peripheral Blood Lymphocytes from Patients with Chronic HTLV-I-Associated Myelopathy/Tropical Spastic Paraparesis and Asymptomatic Carriers by PCR-in situ Hybridization

Less than 5% of people infected with human T-lymphotropic virus type I (HTLV-I) develop HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive neurologic disease. A number of factors have been implicated in the development of HAM/TSP including heterogeneity of viral sequences, host-genetic background, viral-specific cellular immune responses and viral load. This study examined the presence of HTLV-1 tax DNA in peripheral blood lymphocytes (PBL) from 2 chronic HAM/TSP patients and 2 asymptomatic HTLV-I carriers by using PCR-in situ hybridization (PCR-ISH) for the in situ presence of proviral HTLV-I tax DNA. By this technique, rare PBL from these HTLV-I-infected individuals contained HTLV-I DNA. PCR-ISH did not detect any difference in the number of infected cells between HAM/TSP patients and asymptomatic carriers. Copyright 1997 S. Karger AG, Basel

T-cell type primary spinal intramedullary lymphoma associated with human T-cell lymphotropic virus type I after a renal transplant: case report

We present the first report of primary spinal intramedullary lymphoma of the T-cell type associated with human T-cell lymphotropic virus Type I infection in a 52-year-old woman who had undergone a renal transplant. The pathogenesis of spinal cord T-cell lymphoma is discussed.

The myeloneuropathies of Jamaica

This article summarizes the present state of knowledge of TSP/HAM as it is seen in Jamaica. It reviews the historical and clinical aspects of the disease, and shows how the discovery of HTLV-I has generated research in several countries and contributed to a better understanding of the disease. It highlights the need for continued collaboration between basic scientists and clinical neurologists in order that the dilemmas relating to therapy and pathogenicity may be successfully addressed.

Induction of HLA class I and class II expression in human T-lymphotropic virus type I-infected neuroblastoma cells

Human T-lymphotropic virus type I (HTLV-I) is associated with a neurologic disease, HTLV-I-associated myelopathy-tropical spastic paraparesis, in which both pathological and immunological changes are observed within the central nervous system. The pathogenesis of infection in HTLV-I-associated myopathy-tropical spastic paraparesis is not well understood with respect to the cell tropism of HTLV-I and its relationship to the destruction of neural elements. In this study, neuroblastoma cells were infected with HTLV-I by coculturing with HUT-102 cells to demonstrate that cells of neuronal origin are susceptible to this retroviral infection. HTLV-I infection of the neuroblastoma cells was confirmed by verifying the presence of HTLV-I gp46 surface antigens by flow cytometry and by verifying the presence of HTLV-I pX RNA by Northern (RNA) blotting and in situ hybridization techniques. To determine whether HTLV-I infection could potentially lead to changes in cell surface recognition by the immune system, the infected neuroblastoma cells were analyzed for altered HLA expression. The HTLV-I-infected, cocultured neuroblastoma cells were shown, through cell surface antigen expression and RNA transcripts, to express HLA classes I and II. In contrast, cocultured neuroblastoma cells that did not become infected with HTLV-I expressed only HLA class I. HLA class I expression was enhanced by the cytokines tumor necrosis factor alpha and gamma interferon and in the presence of HUT-102 supernatant. In this system, expression of HLA class I and II molecules appeared to be regulated by different mechanisms. HLA class I expression was probably induced by cytokines present in the HUT-102 supernatant and was not dependent on HTLV-I infection. HLA class II expression required HTLV-I infection of the cells. The observation of HTLV-I infection leading to HLA induction in these neuroblastoma cells provides a possible mechanism for immunologic recognition of infected neuronal cells.

Factors affecting outcome after recovery from myocardial infarction

Patients surviving acute myocardial infarction are susceptible to heart failure, recurrence of angina, reinfarction, arrhythmias, and sudden cardiac death. Most deaths occur in the first six months after infarction. Advancing age is the most important nonmodifiable prognostic factor for long-term prognosis, whereas left ventricular function assessed clinically or measured as either ejection fraction or end-systolic volume is the most important modifiable factor. Other significant long-term prognostic factors include: postinfarction angina at rest, inducible ischemia during exercise testing with or without radioisotope imaging, severity and extent of coronary artery disease, patency of the infarct-related artery, late ventricular arrhythmias, decreased heart rate variability, cigarette smoking, hypercholesterolemia, and diabetes mellitus. Identification of these adverse prognostic factors permits risk stratification and enables physicians to determine the most appropriate and cost-effective treatment. Most patients should have a stress test for inducible ischemia and a non-invasive (echo or radionuclide) assessment of left ventricular function. For high-risk patients such as those with prior infarction, heart failure, early postinfarction angina, or frequent late ventricular arrhythmias, coronary angiography and ventriculography prior to discharge are recommended. Assessment of late potentials and heart rate variability will help identify a subgroup of patients at risk for ventricular arrhythmias and cardiac death. However, a more accurate prediction of reinfarction is not possible at present, and no reliable test for atherosclerotic plaque instability has been developed.

The earliest diagnosis of acute myocardial infarction

Acute myocardial infarction results from the cessation of myocardial blood flow caused by thrombotic occlusion of a coronary artery. Rapid restoration of blood flow to the ischemic myocardium minimizes cardiac damage and improves early and long-term morbidity and mortality. Chest pain is the first symptom of myocardial infarction, but in some patients with silent ischemia, the disease can be diagnosed only in retrospect. In symptomatic patients, myocardial infarction should be accurately and promptly diagnosed so that reperfusion therapy can begin immediately. Electrocardiography is the simplest diagnostic modality. Although regional ST-segment elevation is specific, it is not sensitive. In contrast, new computerized algorithms for electrocardiographic analysis and serial monitoring increase sensitivity without decreasing specificity. In the emergency room, echocardiography is used to diagnose patients with no prior history of coronary artery disease whose electrocardiograms proved nondiagnostic. Time-consuming perfusion nuclear studies are inferior to echocardiography but may nevertheless enable physicians to diagnose myocardial infarction in the emergency room. Although the presence of excess creatine kinase is a sign of myocardial necrosis, its increase is delayed for a few hours after coronary occlusion. Doctors can diagnose myocardial infarction as early as two hours after coronary occlusion with the help of simpler automatic assays of MB-creatine kinase mass that use monoclonal antibodies. Other investigational markers of myocardial necrosis include myoglobin and troponin. Elevation of a circulating protein marker also signifies established necrosis, but physicians hope to achieve reperfusion through therapy before irreversible damage occurs.

Nucleotide sequence analysis of HTLV-I isolated from cerebrospinal fluid of a patient with TSP/HAM: comparison to other HTLV-I isolates

Human T-cell leukemia virus type I (HTLV-I) has been associated with adult T-cell leukemia/lymphoma and the chronic neurologic disorder tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). To study the genetic structure of the virus associated with TSP/HAM, we have obtained and sequenced a partial genomic clone from an HTLV-I-positive cell line established from cerebrospinal fluid (CSF) of a Jamaican patient with TSP/HAM. This clone consisted of a 4.3-kb viral sequence containing the 5' long terminal repeat (LTR), gag, and N-terminal portion of the pol gene, with an overall 1.3% sequence variation resulting from mostly nucleotide substitutions, as compared to the prototype HTLV-I ATK-1. The gag and pol regions showed only 1.4% and 1.2% nucleotide variations, respectively. However, the U3 region of the LTR showed the highest sequence variation (3.6%), where several changes appear to be common among certain TSP/HAM isolates. Several of these changes reside within the 21-bp boundaries and the Tax-responsive element. It would be important to determine if the observed changes are sufficient to cause neurologic disorders similar to the murine leukemia virus system or simply reflect the divergent pool of HTLV-I from different geographic locations. At this time, we cannot rule out the possibility that the observed changes have either direct or indirect significance for the HTLV-I pathogenesis in TSP/HAM.

Human T cell leukemia virus type I infection and chronic myelopathy

The central nervous system (CNS) pathology of HTLV-I associated myelopathy or tropical spastic paraparesis (HAM/TSP) is reviewed, based mainly on 12 autopsy cases of Japanese HAM/TSP with a serological confirmation of HTLV-I infection. The essential histopathological feature of HAM/TSP is a chronic progressive inflammatory process heralded by parenchymal infiltration of memory CD4 cells. The inflammation involves both the grey and white matter of the spinal cord, and progresses for more than three years after the onset of neurological symptoms, resulting in preferential degeneration of the white matter. In cases with a history of more than nine years, however, the spinal cord lesions appears degenerative rather than inflammatory. Both the inflammation and the white matter degeneration are most conspicuous in the lower thoracic cord. The lateral funiculus is always and most severely affected. Although the parenchymal tissue degeneration is not confined to any particular long tracts, symmetrical degeneration of the lateral pyramidal tract is evident in all cases. The involvement of the posterior and anterior funiculi is variable and neurons are relatively well preserved. Since evidence for HTLV-I infection in the CNS is limited to detection of proviral DNA by the polymerase chain reaction (PCR) and isolation of the virus from CSF cells, autoimmune nature of the disease is suspected, but is supported by ample evidence for derangements of the host immune system compatible with those of autoimmune diseases. Recent studies on induction of white matter degeneration in the rat with a topographical similarity to human HAM/TSP is also briefly reviewed. However, in the rat disease, inflammatory cell infiltrations are inconspicuous.

Infectivity of human T-lymphotropic virus type I to human nervous tissue cells in vitro

Infectivity of human T-lymphotropic virus type I (HTLV-I) to human nervous tissue cells was explored using co-cultivation with X-irradiated, HTLV-I-producing MT2 cells. Examined cells included normal cerebellar cells, brain tumor cells (astrocytoma, medulloblastoma, meningioma, hemangioblastoma, and schwannoma), and various cell lines (astrocytoma, ependymoma, oligodendroglioma, medulloblastoma, and neuroblastoma). Successful HTLV-I infection was confirmed immunohistochemically using monoclonal antibodies to HTLV-I p19, p24, and pX product. All cell lines and primary cultures from normal cerebellar tissues and brain tumors could be infected with HTLV-I. Double immunostaining showed that glial fibrillary acidic protein-, S-100 protein- or vimentin-positive cells were susceptible to infection. Neurofilament- or neuron-specific enolase-positive cells in medulloblastoma could also be infected. Reverse-transcriptase assay revealed the productive infection in U251-MG (astrocytoma) and KG-IC (oligodendroglioma) lines. Co-cultivated U251-MG cells formed syncytial polykaryons after serial passages, and polymerase chain reaction assay detected HTLV-I genome in U251-MG syncytial polykaryons and p19+ mononuclear cells. HTLV-I viral RNA was also detected in infected U251-MG cells by in situ hybridization. These data show that HTLV-I may have a wide spectrum of infectivity in human nervous tissues.

Geographical subtypes demonstrated by RFLP following PCR in the LTR region of HTLV-I

It has been demonstrated that specific mutations, localized in the long terminal repeat (LTR) region of HTLV-I, allowed to propose the existence of three HTLV-I subtypes. Because some of these mutations created or suppressed the restriction sites for ApaI, NdeI, DraI, SacI, MaeIII, and MaeII enzymes, these endonucleases were used for characterization of further 30 HTLV-I isolates. Seventeen proviral DNA from Japan, five from the Caribbean, one each from French Guyana, the United States, and China, two from Ivory Coast, and three from Zaire were tested. The DNA used were extracted from 26 in vivo peripheral blood mononuclear cell samples and from four cell lines obtained from two Japanese, one Chinese, and one North American patients. Digestions were performed on amplified DNA of the LTR region (nucleotides 31-768). The results confirm the existence of three subtypes of HTLV-I according to LTR sequences. Subtype I was observed only in patients from the Ivory Coast and Zaire. Subtype II was found in the patient from the French West Indies, and in 33% of the samples from Japan. Subtype III was most often observed in the Japanese but also in the Zairian patients.

Tissue expression pattern directed in transgenic mice by the LTR of an HTLV-I provirus isolated from a case of tropical spastic paraparesis

Human T lymphotropic virus type I (HTLV-I) causes adult T cell leukemia/lymphoma and a chronic neurological disease called either tropical spastic paraparesis (TSP) or HTLV-I-associated myelopathy. The different outcomes of this infection could be due to both host and viral factors and it has been proposed that genetic differences could make some HTLV-I strains neurotropic. In this paper, we examined the pattern of tissue-specific expression determined by a long terminal repeat (LTR) obtained from a case of TSP. We constructed transgenic mice in which this LTR controlled the expression of the nlslacZ reporter gene. We observed that in three independent lines of transgenic mice, the reporter gene was expressed predominantly in the central nervous system (CNS), in choroid plexus, and in cells of the hippocampus and cerebellum. Our observations indicate the existence of CNS cells permissive for the expression of HTLV-I and which may be of importance in the pathogenesis of TSP.

Search for human T-cell leukemia virus type I (HTLV-I) proviral sequences by polymerase chain reaction in the central nervous system tissue of HTLV-I-associated myelopathy

Using the polymerase chain reaction (PCR), proviral DNA sequences of the pol and env regions of human T-cell leukemia virus type I (HTLV-I) were directly amplified in paraffin-embedded and frozen tissue sections of active inflammatory central nervous system (CNS) lesions in three autopsy cases of HTLV-I-associated myelopathy (HAM) with serological confirmation. In parallel, the enumeration of UCHL-1 (monoclonal antibody reactive to T-cells) positive cells in the tissue sections subjected to PCR were carried out. Although the control DNA sequence of parathyroid hormone-like peptide gene was definitely amplified, no signals for HTLV-I proviral sequences were detected in these specimens. The number of UCHL-1 positive cell nuclei was almost on the border line of our PCR sensitivity in formalin-fixed tissue, which was estimated to be 20-200 copies. Therefore, it is unlikely that the central nervous system tissue damage in HAM/TSP is a consequence of productive infection of HTLV-I in the CNS tissue.

Human T-cell lymphotropic virus type I sequences detected by nested polymerase chain reactions are not associated with multiple sclerosis

The hypothesis that human T-cell lymphotropic virus type I (HTLV-I) infection is associated with multiple sclerosis (MS) was tested by using primers specific to gag and pol regions of HTLV-I in an analysis that used polymerase chain reactions. No amplification of DNA from patients with MS was detected with primers for either region. After application of a more sensitive scheme with use of nested primers, however, half the samples, including patients with MS and normal control subjects, were found to contain pol DNA sequences. No sequences related to the HTLV-I gag region were detected among patients with MS by using nested primers. Sequences of the amplified HTLV-I pol genomes were determined. Regardless of their origin (MS or normal control), the pol region sequences were similar to HTLV-I sequences reported by other investigators. We conclude that HTLV-I does not have a distinct association with MS, but HTLV-I-related sequences, although in extremely low copy number, may be present in human genomes.

Amplifications of multiple regions of the HTLV-I genome from DNA of an Italian spastic paraparesis patient but not from DNA of multiple sclerosis patients

We searched for evidence of infection by the human T-cell lymphoma/leukemia virus type I (HTLV-I) in patients with multiple sclerosis (40 cases); brainstem encephalitis (1 case); Friedreich's ataxia (1 case); spastic paraparesis of unknown etiology (1 case). All patients were from the region of Abruzzo, Italy. Sera were all negative for anti-HTLV-I reactivity by the Western blotting (WB) analysis. DNAs from peripheral blood mononuclear cells were amplified using the polymerase chain reaction (PCR) technique with primers specific for the HTLV-I gag, pol, and env proviral regions. HTLV-I sequences were amplified only in the patient with spastic paraparesis of unknown etiology. In this case, HTLV-I infection might have been related to blood transfusions received 2 years prior to the onset of the neurologic symptoms. Members of the patient's family were negative for HTLV-I by PCR and WB. These data indicate that HTLV-I associated myelopathy is present also in Italy, but fail to substantiate an association of HTLV-I with multiple sclerosis.

Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy

We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.

HTLV-I-associated myelopathy in a patient with adult T-cell leukemia

Disseminated erythematous papules and plaques developed in a 60-year-old man 3 years before the appearance of neurologic manifestations. A biopsy specimen of the plaque revealed Pautrier's microabscess and a dense mononuclear cell infiltration with atypical convoluted nuclei in the papillary dermis. These cells were helper/inducer T lymphocytes that expressed the interleukin 2 receptor. The patient's white blood cell count was normal, but 1% atypical lymphocytes and a high titer of anti-human T-lymphotropic virus (HTLV)-I antibody were detected in his serum. A smoldering type of adult T-cell leukemia was diagnosed. While he was being treated with PUVA, a gait disturbance developed. A high titer of anti-HTLV-I antibody, characteristic of HTLV-I-associated myelopathy, was demonstrated in his cerebrospinal fluid.

Human T-cell lymphotropic virus type I and II in transfusion medicine

As a consequence of migrating populations, IV drug use and, to a lesser extent, blood transfusions, endemic HTLV-I and HTLV-II infections have spread to nonendemic geographic regions. Although the risk that a person infected with HTLV-I will develop significant disease--even over a lifetime--is estimated to be relatively low, our awareness of the serious diseases associated with other retroviruses requires a cautious approach to blood transfusion. Reports from Japan and the United States indicate that programs testing donated blood and excluding units with HTLV-I antibodies have been highly successful in interrupting the spread of HTLV-I by transfusions. One unanticipated outcome of testing large numbers of people in the United States for HTLV-I antibodies has been recognition of the relatively high prevalence of HTLV-II infection, particularly among IV drug users. The long-term effects of HTLV-II infection are also unknown. Until the natural history and clinical consequences of HTLV-II infection are clearly understood, it is only prudent that blood donated by persons identified to be HTLV-II carriers also be excluded.

Characterization of two human lymphoid cell lines producing human T-lymphotropic virus type I (HTLV-I) isolated from patients with HTLV-I-associated myelopathy or encephalopathy

Two cell lines, CNS-5 and CNS-6, were established by cocultivation of sedimented cells in cerebrospinal fluid (CSF) from two anti-human T-lymphotropic virus type I (HTLV-I) antibody-positive male patients with encephalopathy and HTLV-I-associated myelopathy, respectively, with peripheral blood mononuclear cells from a healthy seronegative female. These cell lines, possessing a normal female karyotype, revealed similar characteristics as follows; they expressed HTLV-I-related antigens, they produced C-type retrovirus particles, HTLV-I provirus genomes were integrated into their DNAs, and they had CD4+ activated T-cell markers. In addition, immunocytochemical and immunoelectron microscopic studies showed peculiar immunoreactivity of these cell lines with anti-alpha/beta T-cell antigen receptor (TCR) antibodies; beta Fl, defining beta chain epitope, was only positive in the perinuclear spaces and rough endoplasmic reticulum in some cells, and WT31, recognizing alpha/beta framework, was mostly negative, while CD3 was expressed in the majority of the cells. These facts indicate that HTLV-I-infected cells were present in CSF of these two patients, and suggest that neurological disorders associated with HTLV-I may not be restricted to myelopathy and may include brain abnormalities.

Sequence variations in LTR and env regions of HTLV-I do not discriminate between the virus from patients with HTLV-I-associated myelopathy and adult T-cell leukemia

For detailed comparison of human T-cell leukemia virus type I (HTLV-I) in adult T-cell leukemia (ATL) and HTLV-I-associated myelopathy (HAM), the nucleotide sequences of parts of the long terminal repeat (LTR) and env regions of the HTLV-I proviruses from 12 patients with HAM, 8 patients with ATL and one with both diseases were analyzed. About 340 bp of the LTR U3 region, about 450 bp of the 5' region and about 280 bp of the 3' region of env were sequenced directly in DNAs amplified by the polymerase chain reaction (PCR) with 2 or 3 sets of primers for each region. Nucleotide insertions, deletions or point mutations were observed at 50 positions in these regions of about 1,000 nucleotides length. None of these changes was specific to either HAM or ATL, and some changes were observed in proviruses from both cases of HAM and ATL. Moreover, the sequences of proviruses isolated from pairs of cell lines established from cerebrospinal fluid (CSF) and peripheral blood mononuclear cells (PBMCs) of the 4 patients with HAM also had different sequences. These results indicate that the proviruses from HAM and ATL are indistinguishable in these sequenced regions, suggesting that these 2 diseases are caused by infection with genetically indistinguishable HTLV-I. Therefore, the reason why these two distinct diseases, HAM and ATL, develop in HTLV-I carriers may be based on a host factor(s) or some other factor(s) rather than variation in the virus itself.