RESUMEN
HTLV-1-Associated Myelopathy (HAM/TSP) is a progressive neuroinflammatory disorder for which no disease-modifying treatment exists. Modest clinical benefit from type I interferons (IFN-α/ß) in HAM/TSP contrasts with its recently identified IFN-inducible gene signature. In addition, IFN-α treatment in vivo decreases proviral load and immune activation in HAM/TSP, whereas IFN-ß therapy decreases tax mRNA and lymphoproliferation. We hypothesize this "IFN paradox" in HAM/TSP might be explained by both cell type- and gene-specific effects of type I IFN in HTLV-1-associated pathogenesis. Therefore, we analyzed ex vivo transcriptomes of CD4+ T cells, PBMCs and whole blood in healthy controls, HTLV-1-infected individuals, and HAM/TSP patients. First, we used a targeted approach, simultaneously quantifying HTLV-1 mRNA (HBZ, Tax), proviral load and 42 host genes with known antiretroviral (anti-HIV) activity in purified CD4+ T cells. This revealed two major clusters ("antiviral/protective" vs. "proviral/deleterious"), as evidenced by significant negative (TRIM5/TRIM22/BST2) vs. positive correlation (ISG15/PAF1/CDKN1A) with HTLV-1 viral markers and clinical status. Surprisingly, we found a significant inversion of antiretroviral activity of host restriction factors, as evidenced by opposite correlation to in vivo HIV-1 vs. HTLV-1 RNA levels. The anti-HTLV-1 effect of antiviral cluster genes was significantly correlated to their adaptive chimp/human evolution score, for both Tax mRNA and PVL. Six genes of the proposed antiviral cluster underwent lentivirus-driven purifying selection during primate evolution (TRIM5/TRIM22/BST2/APOBEC3F-G-H), underscoring the cross-retroviral evolutionary imprint. Secondly, we examined the genome-wide type I IFN response in HAM/TSP patients, following short-term ex vivo culture of PBMCs with either IFN-α or IFN-ß. Microarray analysis evidenced 12 antiretroviral genes (including TRIM5α/TRIM22/BST2) were significantly up-regulated by IFN-ß, but not IFN-α, in HAM/TSP. This was paralleled by a significant decrease in lymphoproliferation by IFN-ß, but not IFN-α treatment. Finally, using published ex vivo whole blood transcriptomic data of independent cohorts, we validated the significant positive correlation between TRIM5, TRIM22, and BST2 in HTLV-1-infected individuals and HAM/TSP patients, which was independent of the HAM/TSP disease signature. In conclusion, our results provide ex vivo mechanistic evidence for the observed immunovirological effect of in vivo IFN-ß treatment in HAM/TSP, reconcile an apparent IFN paradox in HTLV-1 research and identify biomarkers/targets for a precision medicine approach.
RESUMEN
We report changes in the molecular epidemiology of vanA-containing Enterococcus during the intra and interhospital spread of high-risk clones, in Southeastern Brazil. While VRE faecalis predominated during 1998 to 2006, a reversal has been observed in the last years, where VRE faecium belonging to ST114, ST203, ST412, ST478 and ST858 have become endemic.
Asunto(s)
Infección Hospitalaria/epidemiología , Infecciones por Bacterias Grampositivas/epidemiología , Antibacterianos/uso terapéutico , Proteínas Bacterianas/genética , Brasil/epidemiología , Infección Hospitalaria/microbiología , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/genética , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Grampositivas/microbiología , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Epidemiología Molecular/métodos , Resistencia a la Vancomicina/efectos de los fármacosRESUMEN
HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb) infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT) cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have been associated with decreased frequency and functionality of MAIT cells. We hypothesized that HTLV-1 infection is associated with similar perturbations in MAIT cells. We investigated MAIT cell frequency, phenotype, and function by flow cytometry in a cohort of 10 asymptomatic and 10 HAM/TSP HTLV-1 infected patients. We found that MAIT cells from HTLV-1-infected subjects were reduced and showed high co-expression of the activation markers CD38 and HLA-DR but normal levels of CCR6 and CD127. MAIT cells had a lower expression of the transcription factor PLZF in HAM/TSP patients. Unlike Tax-specific CD8+T cells, which are hyperfunctional, MAIT cells from HTLV-1-infected subjects had a poor IFNγ response following antigen stimulation. MAIT cell perturbations in HTLV-1 infection were not associated with HTLV-1 proviral load and MAIT cells were not infected by HTLV-1 in vivo. Rather, MAIT cells loss was associated with immune activation. Overall, our results do not support a role for MAIT cells in HAM/TSP pathogenesis but reduced numbers of MAIT cells, together with their poor functionality, could contribute to the increased susceptibility of HTLV-1-infected individuals to other infectious agents.
Asunto(s)
Infecciones por HTLV-I/patología , Células T Invariantes Asociadas a Mucosa/patología , Adulto , Anciano , Escherichia coli/fisiología , Femenino , Citometría de Flujo , Infecciones por HTLV-I/inmunología , Humanos , Masculino , Persona de Mediana Edad , Células T Invariantes Asociadas a Mucosa/inmunología , Carga ViralAsunto(s)
Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Pollos/microbiología , Enterococcus faecalis/clasificación , Enterococcus faecium/clasificación , Carne/microbiología , Animales , Antibacterianos , Brasil , Contaminación de Alimentos , Microbiología de Alimentos , Pruebas de Sensibilidad MicrobianaAsunto(s)
Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Enterococcus faecium/clasificación , Enterococcus faecium/aislamiento & purificación , Genotipo , Ríos/microbiología , Enterococos Resistentes a la Vancomicina/clasificación , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Antibacterianos/farmacología , Brasil , Enterococcus faecium/genética , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Enterococos Resistentes a la Vancomicina/genéticaRESUMEN
The ability to confirm the diagnosis of human T-lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2) in at-risk individuals in São Paulo, Brazil by Western blotting (WB), conventional polymerase chain reaction (tax and pol PCR) and real-time PCR (pol) is compared. Seventy-three blood samples that were reactive in HTLV-1/2 serological screening enzyme immunoassays (EIAs) were evaluated. HTLV-1/2 was confirmed in 53 blood samples: 48 were positive by WB, 41 were positive by PCR and 42 scored positive by real-time PCR assays (37 of 48 WB-positive samples plus five WB-indeterminate samples that were further confirmed by sequencing). Although WB was able to detect more cases of HTLV-1/2 infection, the real-time PCR assay was able to discriminate between these two viruses and confirm an individual HTLV-1/HTLV-2 diagnosis in two HTLV WB-untyped samples and five WB-indeterminate samples. Because of the large number of WB-indeterminate samples and the cost of the WB assay in Brazil, it is proposed an algorithm that employs two EIAs for screening and then real-time PCR to confirm the infection, followed by testing any PCR-negative samples with the WB assay. This strategy reduces costs and improves the accuracy of the diagnosis of HTLV-1/2.
Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Infecciones por HTLV-I/diagnóstico , Infecciones por HTLV-II/diagnóstico , Virus Linfotrópico T Tipo 1 Humano/aislamiento & purificación , Virus Linfotrópico T Tipo 2 Humano/aislamiento & purificación , Virología/métodos , Adolescente , Adulto , Anciano , Sangre/virología , Western Blotting/métodos , Brasil , Niño , Preescolar , Femenino , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/inmunología , Virus Linfotrópico T Tipo 2 Humano/genética , Virus Linfotrópico T Tipo 2 Humano/inmunología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Adulto JovenRESUMEN
Data obtained during routine diagnosis of human T-cell lymphotropic virus type 1 (HTLV-1) and 2 (HTLV-2) in "at-risk" individuals from São Paulo, Brazil using signal-to-cutoff (S/C) values obtained by first, second, and third generation enzyme immunoassay (EIA) kits, were compared. The highest S/C values were obtained with third generation EIA kits, but no correlation was detected between these values and specific antibody reactivity to HTLV-1, HTLV-2, or untyped HTLV (p=0.302). In addition, use of these third generation kits resulted in HTLV-1/2 false-positive samples. In contrast, first and second generation EIA kits showed high specificity, and the second generation EIA kits showed the highest efficiency, despite lower S/C values. Using first and second generation EIA kits, significant differences in specific antibody detection of HTLV-1, relative to HTLV-2 (p=0.019 for first generation and p<0.001 for second generation EIA kits) and relative to untyped HTLV (p=0.025 for first generation EIA kits), were observed. These results were explained by the composition and format of the assays. In addition, using receiver operating characteristics (ROC) analysis, a slight adjustment in cutoff values for third generation EIA kits improved their specificities and should be used when HTLV "at-risk" populations from this geographic area are to be evaluated.