LUCY SANTOS VILAS BOAS
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
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- Microbial Translocation Is Associated with Extensive Immune Activation in Dengue Virus Infected Patients with Severe Disease(2013) WEG, Cornelia A. M. van de; PANNUTI, Claudio S.; ARAUJO, Evaldo S. A. de; HAM, Henk-Jan van den; ANDEWEG, Arno C.; BOAS, Lucy S. V.; FELIX, Alvina C.; CARVALHO, Karina I.; MATOS, Andreia M. de; LEVI, Jose E.; ROMANO, Camila M.; CENTRONE, Cristiane C.; RODRIGUES, Celia L. de Lima; LUNA, Expedito; GORP, Eric C. M. van; OSTERHAUS, Albert D. M. E.; MARTINA, Byron E. E.; KALLAS, Esper G.Background: Severe dengue virus (DENV) disease is associated with extensive immune activation, characterized by a cytokine storm. Previously, elevated lipopolysaccharide (LPS) levels in dengue were found to correlate with clinical disease severity. In the present cross-sectional study we identified markers of microbial translocation and immune activation, which are associated with severe manifestations of DENV infection. Methods: Serum samples from DENV-infected patients were collected during the outbreak in 2010 in the State of Sao Paulo, Brazil. Levels of LPS, lipopolysaccharide binding protein (LBP), soluble CD14 (sCD14) and IgM and IgG endotoxin core antibodies were determined by ELISA. Thirty cytokines were quantified using a multiplex luminex system. Patients were classified according to the 2009 WHO classification and the occurrence of plasma leakage/shock and hemorrhage. Moreover, a (non-supervised) cluster analysis based on the expression of the quantified cytokines was applied to identify groups of patients with similar cytokine profiles. Markers of microbial translocation were linked to groups with similar clinical disease severity and clusters with similar cytokine profiles. Results: Cluster analysis indicated that LPS levels were significantly increased in patients with a profound pro-inflammatory cytokine profile. LBP and sCD14 showed significantly increased levels in patients with severe disease in the clinical classification and in patients with severe inflammation in the cluster analysis. With both the clinical classification and the cluster analysis, levels of IL-6, IL-8, sIL-2R, MCP-1, RANTES, HGF, G-CSF and EGF were associated with severe disease. Conclusions: The present study provides evidence that both microbial translocation and extensive immune activation occur during severe DENV infection and may play an important role in the pathogenesis.
- Inter- and Intra-Host Viral Diversity in a Large Seasonal DENV2 Outbreak(2013) ROMANO, Camila Malta; LAUCK, Michael; SALVADOR, Felipe S.; LIMA, Celia Rodrigues; VILLAS-BOAS, Lucy S.; ARAUJO, Evaldo Stanislau A.; LEVI, Jose Eduardo; PANNUTI, Claudio Sergio; O'CONNOR, David; KALLAS, Esper GeorgesBackground: High genetic diversity at both inter-and intra-host level are hallmarks of RNA viruses due to the error-prone nature of their genome replication. Several groups have evaluated the extent of viral variability using different RNA virus deep sequencing methods. Although much of this effort has been dedicated to pathogens that cause chronic infections in humans, few studies investigated arthropod-borne, acute viral infections. Methods and Principal Findings: We deep sequenced the complete genome of ten DENV2 isolates from representative classical and severe cases sampled in a large outbreak in Brazil using two different approaches. Analysis of the consensus genomes confirmed the larger extent of the 2010 epidemic in comparison to a previous epidemic caused by the same viruses in another city two years before (genetic distance = 0.002 and 0.0008 respectively). Analysis of viral populations within the host revealed a high level of conservation. After excluding homopolymer regions of 454/Roche generated sequences, we found 10 to 44 variable sites per genome population at a frequency of >1%, resulting in very low intra-host genetic diversity. While up to 60% of all variable sites at intra-host level were non-synonymous changes, only 10% of inter-host variability resulted from non-synonymous mutations, indicative of purifying selection at the population level. Conclusions and Significance: Despite the error-prone nature of RNA-dependent RNA-polymerase, dengue viruses maintain low levels of intra-host variability.
- An outbreak of respiratory syncytial virus infection in hematopoietic stem cell transplantation outpatients: good outcome without specific antiviral treatment(2013) MENDES, E. T.; RAMOS, J.; PEIXOTO, D.; DULLEY, F.; ALVES, T.; BOAS, L. S. Vilas; BATISTA, M. V.; SILVA, D. P. da; LEVIN, A. S.; SHIKANAI-YASUDA, M. A.; COSTA, S. F.Background. Respiratory syncytial virus (RSV) is a common cause of seasonal respiratory viral infection in hematopoietic stem cell transplantations (HSCT) patients. The efficacy of treatment, however, remains controversial. We describe an outbreak of 31 cases of RSV that occurred in an HSCT outpatient care unit in the fall season from March through May 2010, with a good outcome without any specific antiviral treatment. Methods. During these 3 months, 222 nasal wash samples were tested and, of these, 31 outpatients were positive for RSV. In 2009, 99 samples had been tested and only 10 outpatients were positive for RSV in the same period. Results. Seven (22.5%) patients had severe neutropenia (<500 cells/mu L); severe lymphopenia (<200 cells/mu L) was present in 13 (41.9%) patients, and 14 (45%) had received intravenous broad-spectrum antibiotics. Hospitalization was necessary only for 8 patients (25.8%); 20 had lower respiratory tract infection (64.5%). Only 1 patient died as a result of proven invasive aspergillosis. Conclusion. This report suggests that HSCT outpatients with no risk factors may not always require specific treatment for RSV.
conferenceObject DEFINING PP65ENEMIA AND QPCR CUT-OFFS FOR PRE-EMPTIVE THERAPY OF CMV DISEASE IN LOW-RISK RENAL TRANSPLANTED RECIPIENTS(2013) DAVID-NETO, Elias; LEMOS, Angelica Dias; BOAS, Lucy Santos Vilas; LATIF, Acram Zahredine Abdul; AGENA, Fabiana; PAULA, Flavio Jota de; PIERROTI, Ligia; LEMOS, Francine; NAHAS, William Carlos; CAIAFFA FILHO, Helio; PANNUTI, Claudio SergioconferenceObject Defining pp65 Enemia and qPCR Cut-Offs for Pre-Emptive Therapy of CMV Disease in Low-Risk, Seropositive Renal Transplanted Recipients(2013) DAVID-NETO, E.; LEMOS, A.; BOAS, L. Vilas; LATIF, A.; AGENA, F.; PAULA, F. Jota de; PIERROTI, L.; LEMOS, F.; NAHAS, W.; CAIAFFA FILHO, H.; PANUTTI, C.CMV disease mostly invasive gastro-intestinal with low viremia occurs in approximately 16% of CMV seropositive renal transplant recipients not receiving Thymoglobuline (ATG). Pre-emptive therapy (PETh) to avoid disease in this group should cover the majority of patients at risk (high Negative Predictive Value – NPV). To define cut-offs for whole blood real-time quantitative PCR (qPCR) and antigenemia (pp65) assays and use PETh for CMV disease we collected blood samples weekly from day 7 to 120 after TX in pts CMV IgG+/ IgG+ donors who did not receive ATG. Results remained blinded. A suspicion of CMV disease required new qPCR/pp65 or biopsy. The highest value of pp65 and qPCR in pts without CMV disease one week before disease were used in ROC curves. As for Nov 2012, 92 pts had completed the collections or developed disease. They were males (54%), caucasians (69%), mean age 45±14y, 61% deceased donors, all under TAC/MPA/ Prednisone. Overall 12 pts (13%) had CMV disease (11 invasive gastro-intestinal/ 1 syndrome), at 64±21 days (31-98), and 80 did not. Of these 80 pts, 45 (56%) presented at least one episode of asymptomatic viremia and cleared it spontaneously (8 (18%) had PCR+/pp65+; 26 (56%) Pp65+/qPCR- and 11 (24%) qPCR+/Pp65-). Among pts with viremia or disease there was a trend for a higher pp65+ cells for disease than for viremia (152±352vs31±131/10 6 cells, p=0.073,) detected earlier for disease than viremia (64±21vs80±25 days, p=0.049). ROC curves (area 0.902±0.036, p=0.0001) revealed that pp65 of 4 cells had 83% sensitivity and 83% specificity to predict CMV disease. Using this cut-off, the NPV was 97%. The CMV copies detected by qPCR was higher for disease than for viremia (46657±50671 vs 5438±16681 copies, p=0.001) but time for detection was similar for both (74±25 vs 59±18 days, p=NS). ROC curve (area 0.903±0.056,p=0.0001) revealed that qPCR=844 copies had 83% sensitivity and 86% specificity to predict disease with the same NPV of 97%. These data indicate that both methods are adequate to detect CMV disease prior to its development in this low-risk population. Blood samples collection should start at day 30 and then weekly until day 120. When these cut-offs are reached, starting pre-emptive therapy would lead untreated only 3% of patients who would develop CMV disease.