Nicotinamide activates latent HIV-1 ex vivo in ART suppressed individuals, revealing higher potency than the association of two methyltransferase inhibitors, chaetocin and BIX01294

ABSTRACT Background: Latent HIV-1 is a major hurdle in obtaining HIV-1 sustained virological remission (SVR). Here we explored histone deacetylation inhibition property of nicotinamide (NAM; n = 17) for the first time in comparison to a combination of methyltransferase inhibitors (MTIs; Chaetocin and BIX01294; n = 25) to reactivate latent HIV ex vivo in CD8-depleted PBMCs from antiretroviral treated aviremic individuals. Results: NAM reactivated HIV-1 from 13/17 (76.4%) samples compared to 20/25 (80.0%) using MTIs with mean viral load (VLs) of 4.32 and 3.22 log10 RNA copies/mL, respectively (p = 0.004). Mean purging time after NAM and MTIs stimulation was 5.1 and 6.75 days, respectively (p = 0.73). Viral purging in autologous cultures exhibited blunted HIV recovery with fluctuating VLs followed by a complete viral extinction when expanded in allogenic system. Electron microscopy from five supernatants revealed anomalous viral particles, with lack of complete viral genomes when characterized by ultradeep sequencing through metagenomics approach (n = 4). Conclusion: NAM alone was more potent HIV-1 activator than combination of MTIs, with potential of clinical use.

Polyomaviruses BK and JC DNA infection in peripheral blood cells from blood donors

ABSTRACT Objectives: To investigate the prevalence of human polyomavirus (BK and JC viruses) infection in peripheral blood mononuclear cells of healthy blood donors. Methods: The study included 250 healthy blood donors. Five-milliliter blood was drawn into sterile EDTA tubes and PBMCs were isolated from whole blood. The isolated PBMCs were counted and stored at −70 °C for future investigation. DNA was extracted and subjected to simple, sensitive and specific semi-nested PCR as well as QPCR using both general and specific primers for different assays. Results: Of 250 blood samples, 66 (26.4%) were positive for BKV DNA (146-34,514 copies/106 cells). JC DNA was found in 45 (18%) blood samples (65-21,250 copies/106 cells). Co-infection with these viruses were found in 11 (4.4%) out of 250 blood samples. Discussion: Our study provides important data on polyomavirus infection in peripheral blood mononuclear leukocytes in immunocompetent individuals. These data indicate significant differences between the prevalence of BKV and JCV infection in healthy blood donors. The prevalence of BK and JC virus infection is higher in the age range 30-39 years compared to other age ranges.

Evaluation of the cervicovaginal environment in asymptomatic Human T-cell lymphotropic virus type 1 infected women

ABSTRACT Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1) is sexually transmitted and causes persistent infection. This virus induces activation of the immune system and production of inflammatory cytokines. This study aimed to assess the cytokine profile and cytopathological findings in the cervicovaginal fluid of asymptomatic HTLV-1-infected women. Methods: HTLV-1-infected and uninfected women were selected at the Centro de Atendimento ao Portador de HTLV in Salvador-Brazil. None of the included HTLV-1-infected women reported any HTLV-1-associated diseases. All volunteers underwent gynecological examination to collect cervicovaginal fluid. Cytokine quantification was performed using the Cytometric Bead Array (CBA) Human Th1/Th2/Th17 kit. Light microscopy was used to evaluate cervicovaginal cytopathology. In addition, proviral load in cervicovaginal fluid and peripheral blood was measured by real-time quantitative polymerase chain reaction. Results: 112 women (63 HTLV-1-infected and 49 uninfected) were evaluated. No differences were found with respect to cytopathological cervicovaginal findings between the groups. IL-2, TNF, IL-4, IL-10, and IL-17 levels were significantly higher in cervicovaginal fluid of the HTLV-1-infected women than in uninfected women (p < 0.05). Conversely, IFN-γ was found to be lower in the HTLV-1-infected women (p < 0.001) compared to uninfected individuals. Cervicovaginal proviral load was detectable in 53% of the HTLV-1-infected women and was found to be consistently lower than the proviral load in peripheral blood. Conclusions: HTLV-1 infection induces immune activation in cervicovaginal environment, characterized by elevated concentrations of Th1, Th2, and IL17 in the cervicovaginal fluid.

Evaluating the use of fluorescence-based flow cytometry assay for dengue diagnosis using peripheral blood mononuclear cells

Abstract INTRODUCTION: Dengue virus (DENV) is the most important arthropod-borne viral disease worldwide with an estimated 50 million infections occurring each year. METHODS: In this study, we present a flow cytometry assay (FACS) for diagnosing DENV, and compare its results with those of the non-structural protein 1 (NS1) immunochromatographic assay and reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: All three assays identified 29.1% (39/134) of the patients as dengue-positive. The FACS approach and real-time RT-PCR detected the DENV in 39 and 44 samples, respectively. On the other hand, the immunochromatographic assay detected the NS1 protein in 40.1% (56/134) of the patients. The Cohen's kappa coefficient analysis revealed a substantial agreement among the three methods. CONCLUSIONS: The FACS approach may be a useful alternative for dengue diagnosis and can be implemented in public and private laboratories.

Hepatitis C virus in peripheral mononuclear cells in patients on regular hemodialysis

Background: Occult hepatitis C virus infection [OCI] was identified as Hepatitis C virus [HCV], characterized by undetectable HCV antibodies and HCV RNA in serum, while HCV RNA is detectable in liver and peripheral blood mononuclear cells [PBMCs] only. Nosocomial transmission in dialysis units maintains a higher prevalence of hepatitis C virus [HCV] infection in patients on maintenance dialysis than in the general population. HCV infection has a detrimental effect on survival in patients on maintenance dialysis and after renal transplantation. The excess risk for death in HCV-positive patients was partially attributed to chronic liver disease with its attendant complications, particularly hepatocellular carcinoma and liver cirrhosis

The aim of this study: was to evaluate the hidden infection of hepatitis C virus among regular hemodialysis patients in Bab Al Sharia University Hospital with negative ELISA and PCR by using PCR in mononuclear cells as a marker in the serum of these patients

Patients and methods:in this prospective study, 60 patients with end-stage renal disease on regular hemodialysis [for at least 6 months duration] were included. For all patients thorough medical history, clinical examination, kidney function tests, liver function tests, complete blood count, pelvi-abdominal ultrasound, HCVantibodies, hepatitis C viral RNA, quantitative, HbsAg,. HCV PCR done for all patients in serum and mononuclear cells.. Patients with acute or chronic HCV infection as marked by positive hepatitis C antibody,acute or chronic HBV infections marked by hepatitis B surface antigen,other causes of liver dysfunction [e.g., primary biliary cirrhosis, autoimmune hepatitis, HIV infection] and patient on anti HCV treatment.were excluded

Results: showed detection of HCV-PCR in PBMCs in the absence of HCV-PCR in plasma; was found in three of the 60 patients [3.3%]. All patients had negative HIV, HBsAg, HCV Ab and serum HCV PCR

Conclusion: it could be concluded that testing for HCV-RNA in PBMCs is more reliable than hepatitis serological markers in identifying patients with an OCI when a liver biopsy is not available

Epstein-Barr virus load in transplant patients: Early detection of post-transplant lymphoproliferative disorders / Carga de virus Epstein-Barr en pacientes trasplantados: detección temprana de desórdenes linfoproliferativos postrasplante

High levels of circulating EBV load are used as a marker of post-transplant lymphoproliferative disorders (PTLD). There is no consensus regarding the threshold level indicative of an increase in peripheral EBV DNA. The aim of the study was to clinically validate a developed EBV quantification assay for early PTLD detection. Transversal study: paired peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal lymphoid tissue (OLT) from children undergoing a solid organ transplant with (n = 58) and without (n = 47) PTLD. Retrospective follow-up: 71 paired PBMC and plasma from recipients with (n = 6) and without (n = 6) PTLD history. EBV load was determined by real-time PCR. The diagnostic ability to detect all PTLD (categories 1-4), advanced PTLD (categories 2-4) or neoplastic PTLD (categories 3 and 4) was estimated by analyzing the test performance at different cut-off values or with a load variation greater than 0.5 log units. The higher diagnostic performance for identifying all, advanced or neoplastic PTLD, was achieved with cut-off values of 1.08; 1.60 and 2.47 log EBV gEq/10(5) PBMC or 2.30; 2.60; 4.47 log gEq/10(5) OLT cells, respectively. EBV DNA detection in plasma showed high specificity but low (all categories) or high (advanced/neoplastic categories) sensitivity for PTLD identification. Diagnostic performance was greater when: (1) a load variation in PBMC or plasma was identified; (2) combining the measure of EBV load in PBMC and plasma. The best diagnostic ability to identify early PTLD stages was achieved by monitoring EBV load in PBMC and plasma simultaneously; an algorithm was proposed.

La carga alta del virus Epstein-Barr se utiliza como un marcador de desórdenes linfoproliferativos postrasplante (post-transplant lymphoproliferative disorders [PTLD]). El objetivo de este estudio fue validar clínicamente un ensayo de cuantificación del virus Epstein-Barr para la detección temprana de PTLD. Se efectuó un estudio transversal en el que se analizaron muestras pareadas de células mononucleares periféricas (CMP), de plasma y de tejido linfoide orofaríngeo de niños con trasplante de órgano sólido, con PTLD (n = 58) y sin PTLD (n = 47). En el seguimiento retrospectivo se incluyeron 71 muestras pareadas de CMP y de plasma de trasplantados, con PTLD (n = 6) y sin PTLD (n = 6). La carga viral se determinó por PCR en tiempo real. Se estimó la capacidad diagnóstica para detectar PTLD (categorías: todas vs. avanzadas vs. neoplásicas) analizando diferentes valores de corte o una variación de carga mayor de 0,5 logaritmos. El mayor desempeño diagnóstico para identificar todos los PTLD, los avanzados y los neoplásicos, se obtuvo con valores de corte de 1,08; 1,60 y 2,47 log copias/10(5) en CMP y de 2,30; 2,60 y 4,48 log copias/10(5) en células de tejido linfoide orofaríngeo, respectivamente. La detección del ADN del virus Epstein-Barr en el plasma mostró una especificidad alta, pero una sensibilidad baja (todas las categorías) o alta (categorías avanzadas o neoplásicas) para identificar PTLD. Se observó el desempeño diagnóstico más alto en las siguientes condiciones: 1) al identificar una variación de carga en CMP o en plasma; 2) combinando la medición de la carga viral en CMP y en plasma. La mejor capacidad diagnóstica para identificar las etapas tempranas de los PTLD se logró mediante el seguimiento simultáneo de la carga viral en CMP y en plasma; se propone un algoritmo.

Percepción parental de la salud psicofísica, estado nutricional y salud bucal, en relación con características sociodemográficas en niños de Bariloche, Argentina: estudio epidemiológico / Parental perception of psychophysical health, nutritional status and oral health in relation to sociodemographic characteristics in children in Bariloche, Argentina: an epidemiological study

Introducción. Existen evidencias de la asociación de determinantes sociales con la salud infantil. Objetivo. Identificar características sociodemográficas asociadas a desigualdades en la salud infantil y evaluar el efecto acumulado sobre la salud de factores de riesgo basados en estas características. Población y métodos. Evaluamos niños de 4-13 años, de Bariloche, entre junio de 2008 y mayo de 2009. Características sociodemográficas consideradas: nivel socioeconómico, educación materna, embarazo adolescente, cobertura médica, inseguridad y hábitos familiares. Valoramos la percepción parental de la salud física y socioemocional, el estado nutricional y la salud bucal en relación con dichas características y con la acumulación de factores de riesgo. Utilizamos encuesta, antropometría y examen bucal. Resultados. Participaron 180 escolares. El nivel educativo materno se asoció con la salud física, socioemocional y bucal del niño. El porcentaje de niños con piezas faltantes o caries fue 77% entre aquellos cuyas madres, como máximo, habían completado el primario, comparado con 13% entre aquellos cuyas madres habían completado estudios terciarios/universitarios. La posibilidad de percepción de salud física y socioemocional no óptima aumentó con cada factor de riesgo 1,8 y 1,4 veces, respectivamente, y la posibilidad de caries o piezas faltantes se duplicó con cada factor de riesgo adicional. El 27,3% de los escolares presentó sobrepeso y el 8,7%, obesidad, y no se encontró asociación con características sociodemográficas. Conclusiones. El bajo nivel socioeconómico familiar y educativo materno se asoció con una mayor prevalencia de resultados de salud desfavorables. Múltiples factores de riesgo tienen un efecto acumulado sobre la percepción parental de la salud física y socioemocional y la salud bucal.

Introduction. There is evidence of an association between social determinants and child health. Objective. To identify sociodemographic characteristics related to child health inequalities and to analize the cumulative effect on health of risk factors based on these characteristics. Population and Methods. We evaluated 4-13 year-old children in Bariloche between June 2008 and May 2009. The following sociodemographic characteristics were taken into account: socioeconomic level, maternal education, adolescent pregnancy, medical coverage, unsafeness, and family habits. We assessed parental perception of physical, and social and emotional health, nutritional status and oral health in relation to these characteristics and the accumulation of risk factors. We used survey, anthropometry and oral examination. Results. One hundred and eighty students participated. The level of maternal education was associated with the child's physical, social and emotional, and oral health. The percentage of children with missing teeth or cavities reached 77% among those whose mothers had, at most, completed primary school, compared to 13% among those whose mothers had completed tertiary school or university. The possibility of perceiving a non-optimal physical, and social and emotional health increased 1.8 and 1.4 times with each risk factor, respectively, and the possibility of having missing teeth or cavities was twice as much with each additional risk factor. Overweight and obesity was observed in 27.3% and 8.7% of students, respectively, and no relationship was found with sociodemographic characteristics. Conclusions. A low family socioeconomic level and a low maternal education level were associated with a higher prevalence of unfavorable health outcomes. Multiple risk factors have an cumulative effect on parental perception of physical, social and emotional, and oral health.

Receptor expression and responsiveness of human peripheral blood mononuclear cells to a human cytomegalovirus encoded CC chemokine

Human cytomegalovirus is a ubiquitous pathogen that infects the majority of the world's population. After long period of time co-evolving with human being, this pathogen has developed several strategies to evade host immune surveillance. One of the major trick is encoding homologous to those of the host organism or stealing host cellular genes that have significant functions in immune system. To date, we have found several viral immune analogous which include G protein coupled receptor, class I major histocompatibility complex and chemokine. Chemokine is a small group of molecules which is defined by the presence of four cysteines in highly conserved region. The four kinds of chemokines (C, CC, CXC, and CX3C) are classified based on the arrangement of 1 or 2 N-terminal cysteine residues. UL128 protein is one of the analogous that encoded by human cytomegalovirus that has similar amino acid sequences to the human CC chemokine. It has been proved to be one of the essential particles that involved in human cytomegalovirus entry into epithelial/endothelial cells as well as macrophages. It is also the target of potent neutralizing antibodies in human cytomegalovirus-seropositive individuals. We had demonstrated the chemotactic trait of UL128 protein in our previous study. Recombinant UL128 in vitrohas the ability to attract monocytes to the infection region and enhances peripheral blood mononuclear cell proliferation by activating the MAPK/ERK signaling pathway. However, the way that this viral encoded chemokine interacting with peripheral blood mononuclear cells and the detailed mechanism that involving the virus entry into host cells keeps unknown. Here we performed in vitroinvestigation into the effects of UL128 protein on peripheral blood mononuclear cell's activation and receptor binding, which may help us further understand the immunomodulatory function of UL128 protein as well as human cytomegalovirus diffusion mechanism.

High degree of concordance between flow cytometry and geno2pheno methods for HIV-1 tropism determination in proviral DNA

Use of CCR5 antagonists requires previous viral tropism determination. The available methods have high cost, are time-consuming, or require highly trained personnel, and sophisticated equipment. We compared a flow cytometry-based tropism assay with geno2pheno method to determine HIV-1 tropism in AIDS patients, in Bahia, Brazil. We tested peripheral blood mononuclear cells of 102 AIDS patients under antiretroviral therapy by using a cytometry-based tropism assay and geno2pheno assay. Cellular membrane receptors were identified by using CXCR4, CCR5 and CD4 monoclonal antibodies, while detection of cytoplasmic mRNAs for gag and pol HIV regions was achieved by using a labeled probe. Genotypic identification of X4 and R5 tropic viruses was attempted by geno2pheno algorithm. There was a high degree of concordance between cytometry-based tropism assay and geno2pheno algorithm in determination of HIV-1 tropism. Cytometry-based tropism assay demonstrated higher sensitivity and specificity in comparison to geno2pheno, which was used as a gold-standard. One sample could not be amplified by geno2pheno method, but was classified as duotropic by cytometry-based tropism assay. We did not find any association between CD4+ count or plasma HIV-1 RNA viral load and tropism results. The overall performances of cytometry-based tropism assay and geno2pheno assay were almost identical in determination of HIV-1 tropism.

[Investigating the presence of different hepatitis C virus genotypes in serum, peripheral blood mononuclear cells, and liver biopsy specimens of patients with hepatitis C virus infection]

Hepatitis C virus [HCV] is essentially considered as hepatotropic, but virus sequences have also been found in other important extrahepatic sites, including peripheral blood mononuclear cells [PBMCs]. This study was done to investigate the presence of mixed infection and the differences between hepatitis C virus genotypes in plasma, peripheral blood mononuclear cells, and liver biopsy specimens in patients with hepatitis C virus infection. One hundred and fifty two patients with established chronic hepatitis C infection attending Firouzgar Hospital, affiliated to Tehran University of Medical Sciences, from September 2008 to April 2010 were enrolled in the present study. After collecting plasma, peripheral blood mononuclear cell, and liver biopsy specimens, RNA was extracted from the samples and hepatitis C virus genotyping was performed using INNO-LiPATM HCV II kit. The hepatitis C virus genotyping was confirmed by sequencing the RT-nested PCR product of 5'-UTR fragments. The mean age of the participants was 31.2 +/- 16.9 years. Multiple hepatitis C virus genotypes were detected in 4 [2.6%] out of 152 plasma samples, 10 [6.6%] out of 152 peripheral blood mononuclear cell samples, and 9 [18.8%] out of 48 liver biopsy specimens. Hepatitis C virus genotypes were different in the plasma, PBMC, and liver biopsy specimens of 21 [13.8%] patients. The present study shows that a significant proportion of patients with chronic hepatitis C infection are infected by multiple hepatitis C virus genotypes which may not be detectable in their plasma specimens

HIV-1 drug resistance genotypic profiles in children with undetectable plasma viremia during antiretroviral therapy

Treatment of HIV-1 infection with highly active antiretroviral therapy has led to sustained viral suppression in the plasma in a large number of children. However, studies have suggested that the integrated provirus in resting CD4+ T lymphocytes could be a source of reactivatable virus and maintain drug-resistant virus. We evaluated the resistance-related mutations in children receiving antiretroviral therapy with prolonged viral suppression. Thirty-two peripheral blood mononuclear cell samples from 16 children with viral loads that had been below detection limits for at least 12 months were obtained at two different time points and the DNAs sequenced. The median CD4 cell count was 1,016 cells/mm³ (347-2,588) and 938 cells/mm³ (440-3,038) at the first and second time points, respectively. The median follow-up time was 15 months (9-27). Six (37.5 percent) and seven (43.75 percent) of the 16 patients showed at least one NRTI-associated mutation in the first and second samples, respectively. Two out of 16 (12.5 percent) had an NNRTI-associated mutation at the first time point and three out of 16 (18.75 percent) at the second. In addition, 14 out of 16 (87.5 percent) had at least one PI-associated mutation at both time points. Despite plasma HIV-1 RNA suppression for at least 12 months, resistance-related mutations from previous antiretroviral failures could still be detected in archival virus. Furthermore, viral evolution occurred at the reverse transcriptase region in spite of viral suppression to levels below 400 copies/mL. Persistence of archival resistant virus may be relevant when considering future treatment options.

Detection of human herpesvirus-7 by qualitative nested-PCR: comparison between healthy individuals and liver transplant recipients / Detecção de herpesvirus humano-7 por nested-PCR qualitativo: comparação entre indivíduos sadios e receptores de transplante hepático

Diagnosis of human herpesvirus-7 active infection in transplant patients has proved difficult, because this virus is ubiquitous and can cause persistent infections in the host. The significance of viral DNA detected in leukocytes by PCR is unclear and cross-reaction in serological tests may occur. This study aimed to evaluate nested-PCR to detect human herpesvirus-7 active infection in liver transplant recipients compared to healthy individuals. human herpesvirus-7 nested-PCR was performed on leukocytes and sera of 53 healthy volunteers and sera of 29 liver transplant recipients. In healthy volunteers, human herpesvirus-7 was detected in 28.3 percent of leukocytes and 0 percent of serum. human herpesvirus-7 was detected in sera of 48.2 percent of the liver transplant recipients. Nested-PCR on DNA extracted from leukocytes detected latent infection and the study suggests that nested-PCR performed on serum could be useful to detect human herpesvirus-7 active infection in liver transplant recipients.

Diagnóstico da infecção ativa pelo herpesvirus humano-7 é difícil devido ao fato deste vírus ser ubíquo e poder causar infecção persistente no hospedeiro. O significado da detecção do DNA viral por reação em cadeia da polimerase não é claro e, reações cruzadas podem ocorrer em testes sorológicos. O objetivo deste estudo foi avaliar a nested-PCR para detectar infecção ativa pelo herpesvirus-7 em receptores hepáticos comparando com indivíduos sadios. Nested-PCR para herpesvirus-7 foi realizado em leucócitos e soro de 53 voluntários sadios e em soro de 29 receptores hepáticos. Nos voluntários sadios, herpesvirus-7 foi detectado em 28,3 por cento de leucócitos e 0 por cento de soro. herpesvirus-7 foi detectado em soro de 48,2 por cento de receptores hepáticos. Nested-PCR em DNA extraído de leucócitos detectou infecção latente e o estudo sugere que nested-PCR realizada em soro poderia ser útil para detectar infecção ativa por herpesvirus-7 em receptores de fígado.

Detection of HCV by PCR in serum and PBMC of patients with hepatitis C after treatment

Although hepatitis C is mainly hepatotropic, some studies suggest that hepatitis C virus (HCV) infects peripheral blood mononuclear cells (PBMC), using them as a reservoir, which might contribute to the development of resistance to treatment. Fifty-four hepatitis-C patients, who had been submitted to treatment, were selected. Blood samples were collected on the same day for the detection of HCV RNA in serum and PBMC by PCR, using the Amplicor HCV 2.0 assay (Roche Diagnostics). HCV genotyping was performed using the INNO-LiPA HCV kit (Versant, Bayer Diagnostics). HCV RNA was detected in both serum and PBMC in 35 (64 percent) patients and no RNA in 16 (29.6 percent). Disagreement between the serum and PBMC results was observed for three patients (5.6 percent), with HCV RNA being detected in PBMC but not in serum. Four months later, new serum and PBMC samples were collected from one of these patients and HCV RNA was detected in both samples, showing that PBMC can reveal signs of a lack of response to treatment. We conclude that the absence of HCV in the serum of patients with chronic hepatitis C by the end of treatment does not mean that there is no circulating virus. HCV in mononuclear cells may be an indicator of the persisting infection.

Techniques used to identify the Brazilian variant of HIV-1 subtype B

The purpose of the present study was to compare the sensitivity and specificity of V3 enzyme immunoassay (solid phase EIA and EIA inhibition) and restriction fragment length polymorphism (RFLP) with the DNA sequencing "gold standard" to identify the Brazilian HIV-1 variants of subtype B and B"-GWGR. Peripheral blood mononuclear cells were collected from 61 HIV-1-infected individuals attending a clinic in São Paulo. Proviral DNA was amplified and sequentially cleaved with the Fok I restriction enzyme. Plasma samples were submitted to a V3-loop biotinylated synthetic peptide EIA. Direct partial DNA sequencing of the env gene was performed on all samples. Based on EIA results, the sensitivity for detecting B-GPGR was 70 percent, compared to 64 percent for the Brazilian variant B"-GWGR while, the specificity of B-GPGR detection was 85 percent, compared to 88 percent for GWGR. The assessment of RFLP revealed 68 percent sensitivity and 94 percent specificity for the B-GPGR strain compared to 84 and 90 percent for the B"-GWGR variant. Moreover, direct DNA sequencing was able to detect different base sequences corresponding to amino acid sequences at the tip of the V3 loop in 22 patients. These results show a similar performance of V3 serology and RLFP in identifying the Brazilian variant GWGR. However, V3 peptide serology may give indeterminate results. Therefore, we suggest that V3 serology be used instead of DNA sequencing where resources are limited. Samples giving indeterminate results by V3 peptide serology should be analyzed by direct DNA sequencing to distinguish between B-GPGR and the Brazilian variant B"-GWGR.

Comparison of dengue infection in human mononuclear leukocytes with mosquito C6/36 and mammalian Vero cells using flow cytometry to detect virus antigen

Fluorescent activated cell sorter (FACS) analysis is useful for the detection of cellular surface antigens and intracellular proteins. We used this methodology in order to detect and quantify dengue antigens in highly susceptible cells such as clone C6/36 (Aedes albopictus) and Vero cells (green monkey kidney). Additionally, we analyzed the infection in vitro of human peripheral blood mononuclear leukocytes (PBML). FACS analysis turned out to be a reliable technique to quantify virus growth in traditional cell cultures of C6/36 as well as Vero cells. High rates of infection were achieved with a good statistical correlation between the virus amount used in infection and the percentage of dengue antigen containing cells detected in infected cultures. We also showed that human monocytes (CD14+) are preferred target cells for in vitro dengue infection among PBML. Monocytes were much less susceptible to virus infection than cell lines but they displayed dengue antigens detected by FACS five days after infection. In contrast, lymphocytes showed no differences in their profile for dengue specific immunofluorescence. Without an animal model to reproduce dengue disease, alternative assays have been sought to correlate viral virulence with clinical manifestations and disease severity. Study of in vitro interaction of virus and host cells may highlight this relationship.

Estudo da infecçäo pelo HIV-1 na Bahia: determinaçäo da carga viral, características genotípicas e associaçäo com HTLV-I/II / Study of HIV-1 infection in state of Bahia: determination of viral load, genitipic characteristics and association with HTLV-I/II

O conhecimento sobre os mecanismos patogênicos e sobre a cinética da infecçäo pelo virus da imunodeficiência humana levou à rápida expansäo do conjunto de informaçöes acumuladas sobre HIV-1, no curto espaço de tempo que separou a eclosäo dos primeiros casos registrados do momento atual, quando milhöes de indivíduos encontram-se infectados por aquele agente, em todo mundo. A realizaçäo de culturas quantitativas e a detecçäo do genoma viral em plasma ou células do sangue periférico foram fundamentais para ampliaçäo da compreensäo da biologia do HIV-1, levando ao desenvolvimento de estratégias de tratamento e de monitoraçäo da doença cada vez mais eficazes. Entretanto, muitos pontos ainda permanecem obscuros na patogenia da infecçäo pelo HIV-1. No Brasil, as informaçöes sobre o comportamento da infecçäo pelo HIV-1, do ponto de vista de sua interaçäo com o hospedeiro e dos mecanismos determinantes da doença säo escassos. O presente estudo tem como objetivo avaliar a carga viral em células mononucleares do sangue periférico (CMSP) de pacientes infectados pelo HIV-1, em nosso meio, analisando as eventuais associaçöes a fatores ligados ao hospedeiro e ao próprio vírus. Foram realizadas 96 culturas quantitativas de CMSP de 74 pacientes infectados pelo HIV-1, utilizando-se o método de co-cultivo. A caga viral foi expressa em doses infectantes para culturas de tecidos (DICT), e as variaçöes incontradas foram avaliadas de acordo com sexo e idade dos pacientes, estágio clínico da doença, tempo de uso de antivirais, presença de antigenemia p24, para contagem de células CD4+/CD8+, presença de co-infecçäo pelo HTLV-I/II, e subtipo viral. Foi detectada uma associaçäo estatisticamente significante entre co-infecçäo pelo HTLV-I/II e maior carga viral (DICT>50). A contagem de células CD4+ foi significativamente mais elevada entre os pacientes com culturas negativas que entre aqueles com culturas positivas, mas näo foi detectada associaçäo entre elevaçäo da carga viral e níveis mais reduzidos de células CD4+. Houve um predomínio absoluto de subtipos virais B nas amostras estudadas, impossibilitando uma avaliaçäo desta variável como fator potencial de alteraçäo na carga viral. Observou-se um associaçäo estatisticamente significante entre carga viral > 50DICT e co-infecçäo pelos HTLV-I/II. Em conclusäo, a co-infecçäo pelo HTLV-I/II, em nosso estudo, esteve significativamente associada a carga viral mais elevada, levantando a possibilidade de uma possível participaçäo...

Secuencias del genoma del papiloma virus humano, fueron detectadas en células monoclonales de sangre periférica: nuestra experiencia / HPV-DNA sequences detection in peripheral blood mononuclear cells: our experience

El factor inmunológico además del tipo viral, ha sido involucrado en la cronicidad y evolución de las lesiones del TGI por HPV. En este trabajo hemos investigado la presencia de secuencias de DNA de HPV en células mononucleares de sangre periférica (CMSP) de mujeres sanas y con lesiones del TGI atribuídas a infecciones por HPV. Para este estudio se procesaron 84 muestras por técnica de PCR con primers genéricos MY 9 y 11 y posterior hibridación en dot para tipificación con sondas específicas. Los resultados demostraron presencia de DNA de HPV en el 16,4 por ciento de las muestras de CMSP de las cuales el 90 por ciento (9/10) correspondió a lesiones de alto grado y cáncer invasor de cérvix uterino. La presencia de DNA de HPV en CMSP podría alterar las funciones de linfocitos y macrófagos involucrados en la respuesta inmune y jugaría un rol en la epidemiología y patogénesis de las lesiones inducidas por HPV