The FAS-670 AA genotype is associated with high proviral load in peruvian HAM/TSP patients.

Human T-lymphotropic virus 1 (HTLV-1) is the etiologic agent of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Apoptosis is a mechanism of defense elicited by many triggers, including cross-linking of the FAS receptor expressed in viruses-infected cells, and the ligand FASL presented by T-cytotoxic cells. As HAM/TSP has been associated with high levels of proviral load (PVL), we hypothesized that certain genotypes of single-nucleotide polymorphisms (SNPs) associated with a decreased protein expression of FAS and FASL could be risk factors for this disease. Three SNPs: FAS-670A/G (rs1800682), FAS-1377G/A (rs2234767), and FASL-844C/T (rs763110) were analyzed in 73 HAM/TSP patients and 143 HTLV-1 asymptomatic carriers. Ancestry informative markers were used to adjust for ethnicity through a principal component analysis. Gender, age, PVL, and the first three principal components were used as covariates. The FAS/FASL genotype distribution was not associated with HAM/TSP presence (P-> 0.05). The FAS-670 AA genotype was associated with high PVL in comparison to FAS-670 GG in HAM/TSP patients (P = 0.015), while in asymptomatic carriers low levels of PVL were observed (P > 0.05). Our findings suggest that rs1800682, rs2234767, and rs763110 genotypes are not associated with the presence of HAM/TSP, but that the FAS-670 AA genotype can promote higher PVL values in HAM/TSP patients. J. Med. Virol. 89:726-731, 2017. © 2016 Wiley Periodicals, Inc.

CD80+ and CD86+ B cells as biomarkers and possible therapeutic targets in HTLV-1 associated myelopathy/tropical spastic paraparesis and multiple sclerosis.

BACKGROUND: Human T-cell lymphotropic virus (HTLV-1) is the causative agent of the incapacitating, neuroinflammatory disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Currently, there are no disease-modifying therapies with long-term clinical benefits or validated biomarkers for clinical follow-up in HAM/TSP. Although CD80 and CD86 costimulatory molecules play prominent roles in immune regulation and reflect disease status in multiple sclerosis (MS), data in HAM/TSP are lacking. METHODS: Using flow cytometry, we quantified ex vivo and in vitro expression of CD80 and CD86 in PBMCs of healthy controls, HTLV-1-infected individuals with and without HAM/TSP, and MS patients. We hypothesized ex vivo CD80 and CD86 expressions and their in vitro regulation by interferon (IFN)-α/ß mirror similarities between HAM/TSP and MS and hence might reveal clinically useful biomarkers in HAM/TSP. RESULTS: Ex vivo expression of CD80 and CD86 in T and B cells increased in all HTLV-1 infected individuals, but with a selective defect for B cell CD86 upregulation in HAM/TSP. Despite decreased total B cells with increasing disease duration (p = 0.0003, r = -0.72), CD80+ B cells positively correlated with disease severity (p = 0.0017, r = 0.69) in HAM/TSP. B cell CD80 expression was higher in women with HAM/TSP, underscoring that immune markers can reflect the female predominance observed in most autoimmune diseases. In contrast to MS patients, CD80+ (p = 0.0001) and CD86+ (p = 0.0054) lymphocytes expanded upon in vitro culture in HAM/TSP patients. The expansion of CD80+ and CD86+ T cells but not B cells was associated with increased proliferation in HTLV-1 infection. In vitro treatment with IFN-ß but not IFN-α resulted in a pronounced increase of B cell CD86 expression in healthy controls, as well as in patients with neuroinflammatory disease (HAM/TSP and MS), similar to in vivo treatment in MS. CONCLUSIONS: We propose two novel biomarkers, ex vivo CD80+ B cells positively correlating to disease severity and CD86+ B cells preferentially induced by IFN-ß, which restores defective upregulation in HAM/TSP. This study suggests a role for B cells in HAM/TSP pathogenesis and opens avenues to B cell targeting (with proven clinical benefit in MS) in HAM/TSP but also CD80-directed immunotherapy, unprecedented in both HAM/TSP and MS.

Conservative re-treatment of women with atypical endometrial hyperplasia and early endometrial carcinoma: We can hope, at least.

BACKGROUND: In women with recurrent disease who were conservatively treated for atypical endometrial hyperplasia (AEH) and early endometrial carcinoma (EEC), the reasons why conservative treatment was chosen persist and outcomes of performing a conservative re-treatment are unclear, as pooled estimates on oncologic outcomes of such a re-treatment are lacking. OBJECTIVES: To provide pooled estimates of oncologic outcomes of conservative re-treatment in women with recurrent AEH or EC. SEARCH STRATEGY: A systematic review and meta-analysis was performed by searching six electronic databases from their inception to March 2022. SELECTION CRITERIA: Studies that allowed extraction of data about oncologic outcomes of conservative re-treatment of women with recurrent AEH and EEC after a conservative treatment. DATA COLLECTION AND ANALYSIS: Pooled prevalence of complete response (CR), poor response (PR), and recurrence after conservative re-treatment was calculated. MAIN RESULTS: Fifteen studies (12 retrospective and 3 prospective) with 492 women (42.1% AEH and 57.9% EEC) were included in the systematic review, and 10 studies (8 retrospective and 2 prospective) were suitable for the meta-analysis. Pooled prevalence was 85.3% (95% confidence interval [CI] 77.0%-91.0%) for CR, 14.7% (95% CI 9.0%-23.0%) for PR, and 40.4% (95% CI 15.5%-71.4%) for recurrence. CONCLUSIONS: Conservative re-treatment in AEH or EC recurrent women has a high CR rate and acceptable recurrence rate that might allow it to be considered a safe and viable option, at least as a first round of conservative treatment. Women with an unsatisfied desire for motherhood or with high surgical risk might avoid hysterectomy and attempt childbearing or spare high-risk surgery.

Physiotherapy Screening for Referral of a Patient with Patent Foramen Ovale Presenting with Neck Pain as Primary Complaint: A Case Report.

Neck pain is a common musculoskeletal disorder encountered by physiotherapists. However, it may be the early manifestation of more alarming conditions, such as cardiovascular diseases mimicking musculoskeletal pain. Patent foramen ovale (PFO) is a congenital heart defect consisting of a small opening between the right and the left atrium. A 56-year-old male presented with neck pain and head heaviness as primary complaints. The cardiovascular profile and the behavioral symptoms led the physiotherapist to find an exaggerated blood pressure response during exercise; in addition to subtle neurological signs, this prompted the physiotherapist to make an urgent referral. At the emergency department a PFO was diagnosed. To the best of the authors' knowledge, this is the first case to describe a rare clinical presentation of a PFO presenting neck pain as primary complaint. This case report emphasizes the importance for physiotherapists to be able to triage patients for conditions outside their scope suggestive of further medical investigation.

Possible implication of NFKB1A and NKG2D genes in susceptibility to HTLV-1-associated myelopathy/tropical spastic paraparesis in Peruvian patients infected with HTLV-1.

The human T-cell lymphotropic virus type 1 (HTLV-1) is the etiological agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a progressive disease causing paraparesis of the lower limbs. Only a minority of persons infected with HTLV-1 develop HAM/TSP. Universal susceptibility factors for HAM/TSP are not known. The viral genotype is similar in asymptomatic carriers and HAM/TSP patients. High proviral load has been associated consistently with HAM/TSP, but this factor does not explain fully the presence of disease in HTLV-1-infected subjects. Most likely, host genetic factors will play an important role in HAM/TSP development. A two-stage case-control study was carried out to evaluate the association between HAM/TSP and candidate single nucleotide polymorphisms (SNPs) from 45 genes in addition to six human leukocyte antigen (HLA) alleles. Ancestry-informative markers were used to correct for population stratification. Several SNPs belonging to NFKB1A and NKG2D showed a trend of association in both stages. The fact that the direction of the association observed in the first stage was the same in the second stage suggests that NFKB1A and NKG2D may be implicated in the development of HAM/TSP. Further replication studies in independent HTLV-1 patient groups should validate further these associations.

Simultaneous RNA quantification of human and retroviral genomes reveals intact interferon signaling in HTLV-1-infected CD4+ T cell lines.

BACKGROUND: IFN-α contributes extensively to host immune response upon viral infection through antiviral, pro-apoptotic, antiproliferative and immunomodulatory activities. Although extensively documented in various types of human cancers and viral infections, controversy exists in the exact mechanism of action of IFN-α in human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type 1 (HTLV-1) retroviral infections. RESULTS: IFN-α displayed strong anti-HIV-1 effects in HIV-1/HTLV-1 co-infected MT-4 cells in vitro, demonstrated by the dose-dependent inhibition of the HIV-1-induced cytopathic effect (IC50 = 83.5 IU/ml, p < 0.0001) and p24 levels in cell-free supernatant (IC50 = 1.2 IU/ml, p < 0.0001). In contrast, IFN-α treatment did not affect cell viability or HTLV-1 viral mRNA levels in HTLV-1 mono-infected cell lines, based on flow cytometry and nCounter analysis, respectively. However, we were able to confirm the previously described post-transcriptional inhibition of HTLV-1 p19 secretion by IFN-α in cell lines (p = 0.0045), and extend this finding to primary Adult T cell Leukemia patient samples (p = 0.031). In addition, through microarray and nCounter analysis, we performed the first genome-wide simultaneous quantification of complete human and retroviral transciptomes, demonstrating significant transcriptional activation of interferon-stimulated genes without concomitant decrease of HTLV-1 mRNA levels. CONCLUSIONS: Taken together, our results indicate that both the absence of in vitro antiproliferative and pro-apoptotic activity as well as the modest post-transcriptional antiviral activity of IFN-α against HTLV-1, were not due to a cell-intrinsic defect in IFN-α signalisation, but rather represents a retrovirus-specific phenomenon, considering the strong HIV-1 inhibition in co-infected cells.

Accuracy of cytological examination of Tao brush endometrial sampling in diagnosing endometrial premalignancy and malignancy.

Although Tao brush has become one of the most studied and used endometrial cytological samplers, concerns remain about the adequacy of the cytological sample compared with definitive histology. We aimed to assess accuracy of cytological examination from Tao brush sampling in diagnosing endometrial premalignancy and malignancy through a systematic review and meta-analysis. Seven electronic databases were searched from January 2000 to July 2021 for all studies which allowed assessment of accuracy of Tao brush in diagnosing endometrial premalignancy and malignancy. We calculated sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-), diagnostic odds ratio (DOR) and area under the curve (AUC) on summary receiver operating characteristic (SROC) curve. Five studies with 774 patients were included. In diagnosing endometrial premalignancy and malignancy, cytological examination from Tao brush endometrial sampling showed pooled sensitivity of 0.95 (95% CI, 0.90-0.98), specificity of 0.92 (95% CI, 0.90-0.94), LR+ of 12.73 (95% CI, 3.94-41.18), LR- of 0.09 (95% CI, 0.05-0.18), DOR of 184.84 (95% CI, 24.37-1401.79), AUC of 0.9757 (standard error: 0.013). In conclusion, cytological examination from Tao brush seems to have a high diagnostic accuracy and might be proposed as both screening and diagnostic tool. However, further studies are necessary to confirm these findings.

Quantitative real-time polymerase chain reaction for enteropathogenic Escherichia coli: a tool for investigation of asymptomatic versus symptomatic infections.

BACKGROUND: Enteropathogenic Escherichia coli (EPEC) strains are pediatric pathogens commonly isolated from both healthy and sick children with diarrhea in areas of endemicity. The aim of this study was to compare the bacterial load of EPEC isolated from stool samples from children with and without diarrhea to determine whether bacterial load might be a useful tool for further study of this phenomenon. METHODS: EPEC was detected by polymerase chain reaction (PCR) of colonies isolated on MacConkey plates from 53 diarrheal and 90 healthy children aged <2 years. DNA was isolated from stool samples by cetyltrimethylammonium bromide extraction. To standardize quantification by quantitative real-time PCR (qRT-PCR), the correlation between fluorescence threshold cycle and copy number of the intimin gene of EPEC E2348/69 was determined. RESULTS: The detection limit of qRT-PCR was 5 bacteria/mg stool. The geometric mean load in diarrhea was 299 bacteria/mg (95% confidence interval [CI], 77-1164 bacteria/mg), compared with 29 bacteria/mg (95% CI, 10-87 bacteria/mg) in control subjects (P = .016). Bacterial load was significantly higher in children with diarrhea than in control subjects among children <12 months of age (178 vs 5 bacteria/mg; P = .006) and among children with EPEC as the sole pathogen (463 vs 24 bacteria/mg; P = .006). CONCLUSIONS: EPEC load measured by qRT-PCR is higher in diarrheal than in healthy children. qRT-PCR may be useful to study the relationship between disease and colonization in settings of endemicity.

Assessing Cranial Nerves in Physical Therapy Practice: Findings from a Cross-Sectional Survey and Implication for Clinical Practice.

BACKGROUND AND OBJECTIVE: Serious pathologies of the neck can potentially result in cranial nerve palsy. Knowledge about cranial nerve examination (CNE) seems sparse, and its use is still unknown. We aim to investigate the knowledge, skills, and utilization of CNE of Italian physiotherapists. MATERIALS AND METHODS: An online cross-sectional survey. RESULTS: 396 completed the survey, reaching the required sample size. Although Italian physiotherapists consider CNE relevant (mean ± SD = 7.6/10 ± 2.0), over half of all responders (n = 229 (57.8%)) were not trained in the fundamentals and around a third did not use it in their daily practice (n = 138 (34.8%)). Additionally, participants were unconfident and insecure in conducting (n = 152 (38.4%) and n = 147 (37.1%)), interpreting (n = 140 (35.4%) and n = 164 (41.4%)), and managing the CNE (n = 141 (35.6%) and n = 154 (38.9%)). Possessing a musculoskeletal specialization was associated with an increased value attributed to clinical practice guidelines and reduced the lack of confidence in conducting, interpreting, and managing the CNE (respectively, n = 35 (25.5%), p = 0.0001; n = 32 (23.4%) p = 0.0002; n = 32 (23.4%) p = 0.0002). Working in a direct access setting significantly increased the considered relevance of guidelines and the concerns about arterial (p = 0.004) and other serious pathologies (p = 0.021). Pain and visual disturbances were considered the main indicators to CNE, demonstrating limited knowledge of signs and symptoms' indicating CNE. Participants considered specific training in CNE as relevant (mean ± SD = 7.6/10 = 2.1). CONCLUSIONS: a substantial proportion of Italian physiotherapists are not schooled in the fundamentals of cranial nerve examination. Given the number of physiotherapists who work in first contact roles, this is a professional concern.

Evaluation of host genetic and viral factors as surrogate markers for HTLV-1-associated myelopathy/tropical spastic paraparesis in Peruvian HTLV-1-infected patients.

Human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a complication that affects up to 5% of HTLV-1-infected individuals. Several host genetic and viral factors have been associated with the risk of HAM/TSP. The aim of this study was to evaluate the performance of a prognostic model for HAM/TSP developed in Japan in a Peruvian population of 71 HAM/TSP patients and 94 asymptomatic carriers (ACs). This model included age, proviral load (PVL), the presence of HLA-A*02 and HLA-Cw*08 alleles, SDF-1 +801, and TNF-alpha -863 polymorphisms, and viral subgroup. We describe frequencies for the four host genetic markers and demonstrate the presence of the HTLV-1 tax B subgroup in Peru. Using cross-validation, we show that the predictive ability of the prognostic model, as characterized by the area under the receiver-operating characteristic curve (AUC), does not differ from a model containing PVL only (both AUC = 0.74). We found some suggestive evidence of a protective effect of the HLA-A*02 allele but failed to replicate the associations with the other three genetic markers and with viral subgroup. A logistic model containing PVL, age, gender, and HLA-A*02 provided the best predictive ability in the Peruvian cohort (AUC = 0.79). J. Med. Virol. 82:460-466, 2010. (c) 2010 Wiley-Liss, Inc.

IFN-gamma production in response to Tax 161-233, and frequency of CD4+ Foxp3+ and Lin HLA-DRhigh CD123+ cells, discriminate HAM/TSP patients from asymptomatic HTLV-1-carriers in a Peruvian population.

Human T-lymphotropic virus 1 (HTLV-1) can cause HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The objective of this study was to gain insight into the pathogenesis of HAM/TSP by focusing on the CD8(+) T-cell response. Twenty-three HTLV-1-seronegative controls (SC), 29 asymptomatic HTLV-1 carriers (AC) and 48 patients with HAM/TSP were enrolled in the study. We evaluated the production of interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells stimulated with Tax overlapping peptides, the expression of genes related to the CD8(+) cytotoxic T-cell response, the frequency of CD4(+) Foxp3(+) cells and of dendritic cells, and the HTLV-1 provirus load (PVL). The frequency of cells producing IFN-gamma in response to Tax 161-233, but not to Tax 11-19, discriminated patients with HAM/TSP from AC. The increased pro-inflammatory response observed in patients with HAM/TSP was shared by AC with a high PVL, who also exhibited lower levels of granzyme H mRNA in unstimulated CD8(+) T cells than AC with a low PVL. Patients with HAM/TSP showed higher frequencies of CD4(+) Foxp3(+) cells and lower frequencies of plasmacytoid dendritic cells (pDC) than AC. Our findings are consistent with a model in which HTLV-1, along with the host genetic background, drives quantitative and qualitative changes in pDC and CD4(+) Foxp3(+) cells that lead to a predominance of inflammatory responses over lytic responses in the CD8(+) T-cell response of individuals predisposed to develop HAM/TSP.

Development and validation of a multiplex real-time PCR assay for simultaneous genotyping and human T-lymphotropic virus type 1, 2, and 3 proviral load determination.

The human T-lymphotropic virus (HTLV) proviral load remains the best surrogate marker for disease progression. Real-time PCR techniques have been developed for detection and quantification of cosmopolitan HTLV type 1a (HTLV-1a) and HTLV-2. Since a growing level of diversity in subtypes and genotypes is observed, we developed a multiplex quantitative PCR for simultaneous detection, genotyping, and quantification of proviral loads of HTLV-1, 2, and 3. Our assay uses tax type-specific primers and dually labeled probes and has a dynamic range of 10(5) to 10 HTLV copies. One hundred sixty-three samples were analyzed, among which all of the different subtypes within each HTLV genotype could be detected. The performance of proviral load determination of our multiplex assay was compared with that of a previously published HTLV-1 singleplex quantitative PCR based on SYBR green detection, developed at a different institute. Linear regression analysis showed a statistically significant (P < 0.0001) and strong (r(2) = 0.87) correlation between proviral load values measured with the two distinct real-time PCR assays. In conclusion, our novel assay offers an accurate molecular diagnosis and genotyping, together with the determination of the proviral load of HTLV-infected individuals, in a single amplification reaction. Moreover, our molecular assay could offer an alternative when current available serological assays are insufficient.

A Fashi Lymphoproliferative Phenotype Reveals Non-Apoptotic Fas Signaling in HTLV-1-Associated Neuroinflammation.

Human T-cell lymphotropic virus (HTLV)-1 was the first human retrovirus to be associated to cancer, namely adult T-cell leukemia (ATL), but its pathogenesis remains enigmatic, since only a minority of infected individuals develops either ATL or the neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A functional FAS -670 polymorphism in an interferon (IFN)-regulated STAT1-binding site has been associated to both ATL and HAM/TSP susceptibility. Fashi T stem cell memory (Tscm) cells have been identified as the hierarchical apex of ATL, but have not been investigated in HAM/TSP. In addition, both FAS and STAT1 have been identified in an IFN-inducible HAM/TSP gene signature, but its pathobiological significance remains unclear. We comprehensively explored Fas expression (protein/mRNA) and function in lymphocyte activation, apoptosis, proliferation, and transcriptome, in PBMC from a total of 47 HAM/TSP patients, 40 asymptomatic HTLV-1-infected individuals (AC), and 58 HTLV-1 -uninfected healthy controls. Fas surface expression followed a two-step increase from HC to AC and from AC to HAM/TSP. In HAM/TSP, Fas levels correlated positively to lymphocyte activation markers, but negatively to age of onset, linking Fashi cells to earlier, more aggressive disease. Surprisingly, increased lymphocyte Fas expression in HAM/TSP was linked to decreased apoptosis and increased lymphoproliferation upon in vitro culture, but not to proviral load. This Fashi phenotype is HAM/TSP-specific, since both ex vivo and in vitro Fas expression was increased as compared to multiple sclerosis (MS), another neuroinflammatory disorder. To elucidate the molecular mechanism underlying non-apoptotic Fas signaling in HAM/TSP, we combined transcriptome analysis with functional assays, i.e., blocking vs. triggering Fas receptor in vitro with antagonist and agonist-, anti-Fas mAb, respectively. Treatment with agonist anti-Fas mAb restored apoptosis, indicating biased, but not defective Fas signaling in HAM/TSP. In silico analysis revealed biased Fas signaling toward proliferation and inflammation, driven by RelA/NF-κB. Correlation of Fas transcript levels with proliferation (but not apoptosis) was confirmed in HAM/TSP ex vivo transcriptomes. In conclusion, we demonstrated a two-step increase in Fas expression, revealing a unique Fashi lymphocyte phenotype in HAM/TSP, distinguishable from MS. Non-apoptotic Fas signaling might fuel HAM/TSP pathogenesis, through increased lymphoproliferation, inflammation, and early age of onset.

Cryopreservation modulates the detection of regulatory T cell markers.

BACKGROUND: Regulatory T cells (Tregs) modulate the host response in infectious diseases and are key mediators of peripheral tolerance. Cryopreservation of peripheral blood mononuclear cells (PBMCs) is commonly used in immunological field studies where access to complex laboratory tests is not feasible. Our objective is to assess the effects of cryopreservation on the flow cytometric detection of surface and intracellular markers of Tregs. METHODS: Heparinized venous blood was obtained from 36 healthy individuals and 15 HIV-1 infected subjects. PBMCs were isolated and stained for surface and intracellular markers of Tregs. PBMCs from each subject were cryopreserved in liquid nitrogen with DMSO; these cells were thawed and stained at a later date. All samples were analyzed by flow cytometry. The proportion of Tregs was compared using Wilcoxon signed-rank test. RESULTS: Cryopreservation decreased the proportion of Tregs identified by surface and intracellular markers in healthy individuals and in HIV-1 patients. The proportion of CD4+CD25+FoxP3+ was decreased from 3.13 to 2.16% (P < 0.001) for non-HIV subjects and from 2.68 to 0.94% (P < 0.001) for HIV subjects, compared to fresh samples. Significant reduction was also observed for CD4+CD25+CD127lo-neg. However, the effect varied considerably between samples. The effect was similar among HIV and non-HIV patients (P = 0.38). CONCLUSIONS: Cryopreservation modulates the detection of surface and intracellular markers of Tregs. These results confirm that research on Tregs, including studies of HIV-1 infected patients, should be carried out prospectively on fresh samples in order to obtain unbiased conclusions. Results using cryopreserved cells should be regarded as only preliminary.

Ascorbic acid has superior ex vivo antiproliferative, cell death-inducing and immunomodulatory effects over IFN-α in HTLV-1-associated myelopathy.

BACKGROUND: Clear therapeutic guidelines for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) are missing due to the lack of randomized double-blind controlled clinical trials. Moderate yet similar clinical benefit has been demonstrated for IFN-α and high-dose ascorbic acid (AA) monotherapy in a large open clinical trial. However, there is a lack of in vivo and in vitro studies exploring and comparing the effects of high-dose AA and IFN-α treatment in the context of HAM/TSP. Therefore, we performed the first comparative analysis of the ex vivo and in vitro molecular and cellular mechanisms of action of IFN-α and high-dose AA in HAM/TSP. PRINCIPAL FINDINGS: Through thymidine incorporation and quantification of Th1/Th2/Th17 cytokines, we demonstrate that high-dose AA displays differential and superior antiproliferative and immunomodulatory effects over IFN-α in HAM/TSP PBMCs ex vivo. In addition, high-dose AA, but not IFN-α, induced cell death in both HAM/TSP PBMCs and HTLV-1-infected T-cell lines MT-2 and MT-4. Microarray data combined with pathway analysis of MT-2 cells revealed AA-induced regulation of genes associated with cell death, including miR-155. Since miR-155 has recently been demonstrated to up-regulate IFN-γ, this microRNA might represent a novel therapeutic target in HAM/TSP, as recently demonstrated in multiple sclerosis, another neuroinflammatory disease. On the other hand, IFN-α selectively up-regulated antiviral and immune-related genes. CONCLUSIONS: In comparison to IFN-α, high-dose AA treatment has superior ex vivo and in vitro cell death-inducing, antiproliferative and immunomodulatory anti-HTLV-1 effects. Differential pathway activation by both drugs opens up avenues for targeted treatment in specific patient subsets.

Short communication an interferon-γ ELISPOT assay with two cytotoxic T cell epitopes derived from HTLV-1 tax region 161-233 discriminates HTLV-1-associated myelopathy/tropical spastic paraparesis patients from asymptomatic HTLV-1 carriers in a Peruvian population.

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic and progressive disorder caused by the human T-lymphotropic virus type 1 (HTLV-1). In HTLV-1 infection, a strong cytotoxic T cell (CTL) response is mounted against the immunodominant protein Tax. Previous studies carried out by our group reported that increased IFN-γ enzyme-linked immunospot (ELISPOT) responses against the region spanning amino acids 161 to 233 of the Tax protein were associated with HAM/TSP and increased HTLV-1 proviral load (PVL). An exploratory study was conducted on 16 subjects with HAM/TSP, 13 asymptomatic carriers (AC), and 10 HTLV-1-seronegative controls (SC) to map the HAM/TSP-associated CTL epitopes within Tax region 161-233. The PVL of the infected subjects was determined and the specific CTL response was evaluated with a 6-h incubation IFN-γ ELISPOT assay using peripheral blood mononuclear cells (PBMCs) stimulated with 16 individual overlapping peptides covering the Tax region 161-233. Other proinflammatory and Th1/Th2 cytokines were also quantified in the supernatants by a flow cytometry multiplex assay. In addition, a set of human leukocyte antigen (HLA) class I alleles that bind with high affinity to the CTL epitopes of interest was determined using computational tools. Univariate analyses identified an association between ELISPOT responses to two new CTL epitopes, Tax 173-185 and Tax 181-193, and the presence of HAM/TSP as well as an increased PVL. The HLA-A*6801 allele, which is predicted to bind to the Tax 181-193 peptide, was overpresented in the HAM/TSP patients tested.

Role of killer cell immunoglobulin-like receptor gene content and human leukocyte antigen-C group in susceptibility to human T-lymphotropic virus 1-associated myelopathy/tropical spastic paraparesis in Peru.

Human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) affects approximately 5% of HTLV-1-infected individuals. It is poorly understood why only some infected subjects develop this disease, but host genetic factors may determine susceptibility. The innate immune system may influence disease outcome in HTLV-1-infected individuals because of its role in early immune responses to viral infections. Variation in genes encoding killer cell immunoglobulin-like receptors (KIR) and their human leukocyte antigen (HLA) molecule ligands may affect the risk of HAM/TSP. We performed a two-stage case-control study to examine the distribution of KIR genes and HLA-Cw groups in Peruvian HTLV-1-infected HAM/TSP individuals and asymptomatic carriers. We also tested for epistatic effects between specific KIR genes and HLA-Cw groups. In the first stage, we found several trends toward association with HAM/TSP or proviral load (PVL). However, these results were not replicated in the second stage. In conclusion, this is the first report on KIR gene frequencies in the Peruvian population and may be of significance in hematopoietic stem-cell transplants. Our study did not reveal significant associations between KIR genes and HLA-Cw groups and HAM/TSP or PVL. However, because our study was powered to detect only larger effects, additional studies using larger cohorts are needed.

Regulatory T cell expansion in HTLV-1 and strongyloidiasis co-infection is associated with reduced IL-5 responses to Strongyloides stercoralis antigen.

BACKGROUND: Human strongyloidiasis varies from a chronic but limited infection in normal hosts to hyperinfection in patients treated with corticosteroids or with HTLV-1 co-infection. Regulatory T cells dampen immune responses to infections. How human strongyloidiasis is controlled and how HTLV-1 infection affects this control are not clear. We hypothesize that HTLV-1 leads to dissemination of Strongyloides stercoralis infection by augmenting regulatory T cell numbers, which in turn down regulate the immune response to the parasite. OBJECTIVE: To measure peripheral blood T regulatory cells and Strongyloides stercoralis larval antigen-specific cytokine responses in strongyloidiasis patients with or without HTLV-1 co-infection. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from newly diagnosed strongyloidiasis patients with or without HTLV-1 co-infection. Regulatory T cells were characterized by flow cytometry using intracellular staining for CD4, CD25 and FoxP3. PBMCs were also cultured with and without Strongyloides larval antigens. Supernatants were analyzed for IL-5 production. RESULTS: Patients with HTLV-1 and Strongyloides co-infection had higher parasite burdens. Eosinophil counts were decreased in the HTLV-1 and Strongyloides co-infected subjects compared to strongyloidiasis-only patients (70.0 vs. 502.5 cells/mm(3), p = 0.09, Mann-Whitney test). The proportion of regulatory T cells was increased in HTLV-1 positive subjects co-infected with strongyloidiasis compared to patients with only strongyloidiasis or asymptomatic HTLV-1 carriers (median = 17.9% vs. 4.3% vs. 5.9 p<0.05, One-way ANOVA). Strongyloides antigen-specific IL-5 responses were reduced in strongyloidiasis/HTLV-1 co-infected patients (5.0 vs. 187.5 pg/ml, p = 0.03, Mann-Whitney test). Reduced IL-5 responses and eosinophil counts were inversely correlated to the number of CD4+CD25+FoxP3+ cells. CONCLUSIONS: Regulatory T cell counts are increased in patients with HTLV-1 and Strongyloides stercoralis co-infection and correlate with both low circulating eosinophil counts and reduced antigen-driven IL-5 production. These findings suggest a role for regulatory T cells in susceptibility to Strongyloides hyperinfection.