Torque teno virus (TTV) is prevalent in Brazilian non-human primates and chickens (Gallus gallus domesticus) / Torque teno virus (TTV) es prevalente en primates no humanos brasileños y pollos (Gallus gallus domesticus)

Torque Teno virus (TTV) is an infectious agent of worldwide distribution isolated by the first time as the agent of an acute post-transfusion hepatitis in a patient in Japan. It has been classified into a new floating genus called Anellovirus. Recent studies showed that TTV can also be identified in serum specimens obtained from domesticated farm animals and from non-human primates. To better understand the relationship between TTV and their hosts, a study to detect virus in the serum and whole blood of Brazilian non-human primates and in the plasm of chickens was performed by applying the PCR-UTR-A technique, followed by a genomic sequence and phylogenetic analysis. By nested-PCR-UTR, the DNA of TTV was detected in sera from 4 (5.3 percent) of 75 Cebus apella, 2 (40 percent) of 5 Alouatafusca, 1 (20 percent) of 5 Alouata caraya, 1 (5.2 percent) of 19 Callithrixpenicilata, 1 (4 percent) of 25 Callithrixjacchus, 1 (20 percent) of 5 Saimiri sciureus and 1 (25 percent) of 4 Leontopithecus chrysomelas. Phylogenetic analysis revealed that sequences detected in 8 samples clustered with TTV sequences So-TTV2 (Sagüínus oedipus) and At-TTV3 (Aotes Trivirgatus). Three sequences showed similarity with a human Torque Teno Minivirus (TLMV). TTV ORF2 DNA was detected in one sera sample and one whole blood sample of non-human primates and in one plasm sample of chicken. Phylogenetic analysis revealed that the sequences amplified by the ORF2 region show no difference between human, non-human primates and chicken. This is the first report of TTV in Brazilian new world non-human primates and chicken.

Torque Teno virus (TTV) es una agente infeccioso de distribución mundial, aislado por primera vez como el agente de una hepatitis aguda posterior a la transfusión de un paciente en Japón. Se ha clasificado en un nuevo género flotante llamado Anellovirus. Recientes estudios han demostrado que TTV también puede ser identificado en el suero de especímenes obtenidos desde granjas de animales domésticos y desde primates no humanos. Para entender mejor la relación entre la TTV y sus huéspedes, fue realizado un estudio para detectar el virus en el suero y la sangre de primates no humanos brasileños y en el plasma de pollos mediante la aplicación de la técnica PCR-UTR-A, seguida de una secuencia genómica y análisis filogenético. Por medio de PCR-UTR-anidado, el ADN de TTV fue detectado en sueros de 4 de 75 (5,3 por ciento)Cebus apella, 2 de 5 (40 por ciento) Alouata fusca, 1 de 5 (20 por ciento) de Alouata caraya, 1 de 19 (5,2 por ciento) de Callithrixpenicilata, 1 de 25 (4 por ciento) Callithrixjacchus, 1 de 5 (20 por ciento) de Saimiri sciureus y 1 de 4 (25 por ciento) de Leontopithecus chrysomelas. El análisis filogenético reveló secuencias detectadas en 8 muestras agrupadas con TTV secuencias So-TTV2 (Sagüínus oedipus) y At-TTV3 (Aotes Trivirgatus). Tres secuencias mostraron similitud con el Torque Teno Minivirus humano (TLMV). Fue detectado TTV ORF2 ADN en una muestra de suero y una muestra de sangre de primates no-humanos y en una muestra de plasma de pollo. El análisis filogenético reveló que las secuencias amplificadas por la región ORF2 no muestran ninguna diferencia entre humanos, primates no humanos y pollos. Este es el primer informe de nuevos TTV en primates-no humanos brasileños y en pollos.

Research of torque teno virus (TTV) in serum and total blood of Brazilian non-human primates and in chicken plasma (Gallus gallus domesticus) by the PCR N22 region / Investigación de Torque teno virus (TTV) en suero y sangre de primates no humanos brasileños y en plasma de pollo (Gallus gallus domesticus) por PCR en la region N22

Torque teno virus (TTV) is a recently discovered DNA virus that was originally isolated from a Japanese patient (initials, TT) with post-transfusion hepatitis of unknown aetiology. TTV is an circular DNA virus classified recently together with related Torque teño minivirus, into a new genus called Anellovirus. Infection TTV has been detected in a range of non-human primates as well as domestic animals. The purpose of this study was to search TTV in the serum and total blood of Brazilian monkeys and in plasma of domestic chickens by seminested PCR of coding region (N22), followed by a genomic sequence and phylogenetic analysis. No serum sample was amplified. TTV DNA was detected in total blood from 3 (4 percent) out of 75 brown-capuchin (Cebus apella) and from 1 (25 percent) out of 4 golden-headed lion-tamarin (Leontopithecus chrysomelas). Phylogenetic analysis revealed that one sample showed similarity with one sequence of the cotton top tamarin (Saguinus oedipus) (So-TTV2) and with one of the douroucoulis (ão tes trivirgatus) (At-TTV3). Two samples showed similarity with a human Torque Teño Mini Virus (TLMV). The other sample clustered with one sequence of the chimpanzee (Pt-TTV6) and with the human TTV strain TA278. The plasma chicken samples tested were all negative. The amino acid sequences reported in this study are the first obtained in Brazil from total blood of non-human primates naturally infected by TTV.

Torque teno virus (TTV) es un virus de ADN recientemente descubierto que fue inicialmente aislado de un paciente japonés (iniciales TT) después de la transfusión de hepatitis de etiología desconocida. TTV es un virus de ADN circular recientemente clasificado junto con los torque teno minivirus, en un nuevo género llamado Anellovirus. La infección de TTV se ha detectado en una serie de primates no humanos, así como animales domésticos. El objetivo de este estudio fue buscar TTV en el suero y sangre total de monos de Brasil y en el plasma de pollos domésticos, por seminested PCR de la región de codificación (N22), seguido de una secuencia genómica y el análisis filogenético. Las muestras que no eran suero fueron amplificadas. TTV DNA se detectó en sangre total de 3 (4 por ciento) de un total de 75 capuchinos de cabeza dura (Cebus apella) y de 1 (25 por ciento) de un total de 4 tití- león de cabeza dorada (Leontopithecus chrysomelas). El análisis filogenético demostró que una muestra presentaba similitud con una secuencia de Saguinus Edipo (So-TTV2) y con una de Aotes trivirgatus (A-TTV3). Dos muestras mostraron similitud con un torque teno mini virus (TLMV) humano. La otra muestra agrupada con una secuencia de los chimpancés (PT-TTV6) y con el TTV humanos cepa TA278. El análisis de las muestras de plasma de pollo fueron negativas Las secuencias de aminoácidos que se reportan en este estudio son las primeras obtenidas en Brasil de sangre de primates no humanos infectados naturalmente por TTV.

HIV-1 viremia during the first 28 weeks of pregnancy is not associated with mother-to-child transmission

It is currently recommended that antiretroviral prophylaxis to prevent mother-to-child transmission (MTCT) of HIV be initiated at 14 weeks of gestation. However, the relevance of early-gestation HIV viral load level for intrauterine MTCT is unknown. The objective of this study was to determine the relationship between prenatal maternal viral load and intrauterine MTCT. Records of HIV-infected pregnant women in two centers in Brazil, from 1999 to 2004 were analyzed. Three pregnancy periods were considered: earlier than 14 weeks, 14 to 27 6/7 weeks, and 28 weeks of gestation or more. Peripartum HIV exposure was also computed. Maximum viral load in each period was the measure of HIV exposure. Four hundred fifty-seven HIV-infected pregnant women were evaluated, but 53 were excluded. The MTCT rate was 0.49 percent (2/404-95 percent confidence interval (CI95) = 0.14-1.79 percent). Newborns were not breast-fed. Median viral load for the earlier-than-14-week period was 9,900 copies/mL (P25-75 1,000-50,775 copies/mL), 8,350 copies/mL (P25-75 707-42,000 copies/mL) for the 14 to 27 6/7-week period, and 435 copies/mL (P25-75 90-7,775 copies/mL) after the 28-week period. The peripartum median viral load was 400 copies/mL (P25-75 80-500 copies/mL). MTCT in mothers with VL > 1,000 copies/mL during the first 14 weeks (0.67 percent, 2/298) was not different from those with VL =1,000 copies/mL (0.0 percent, 0/96, P=1). Analogously, in the 14 to 27 6/7-week period, MTCT was similar in groups with VL higher (0.68 percent, 2/292) or lower (0 percent, 0/106) than 1,000 copies/mL (P=1). Regarding VL >1,000 copies/mL at 28-weeks-or-later and at peripartum periods, MTCT rates were 1.15 percent (2/173, P = 0.18) and 2.8 percent (2/71, P = 0.03), respectively. Intrauterine transmission does not seem to be influenced by HIV viremia during the first 28 weeks of pregnancy.

Induction of interleukin-10 by HIV antigens in peripheral mononuclear cells of health care workers after occupational exposure to HIV-1-positive blood

Evaluation of HIV-induced IL-2 production by peripheral blood mononuclear cells (PBMC) and HIV-specific T helper and cytotoxic T lymphocyte (CTL) responses in health care workers (HCW) occupationally exposed to HIV reveals a high rate of response to HIV among non-seroconverters. IL-10 is also known to interfere with HIV infection in vitro. To evaluate the induction of IL-10 by HIV antigens in HCW occupationally exposed to HIV, 18 HCW with percutaneous injury were enrolled in this study, 9 of them exposed to HIV-contaminated blood, and 9 exposed to HIV-negative blood. PBMC were incubated on plates coated with HIV-1 antigens, and IL-10 was measured in supernatants by ELISA. Five of nine HCW exposed to HIV-contaminated blood presented HIV-induced IL-10. Two of nine HCW exposed to HIV-negative source patients also had detectable levels of HIV-induced IL-10, one of them in the sample obtained on the day of accidental exposure. There was a relationship between the type of device involved in injury and IL-10 production. Individuals exposed to hollow needles or scalpels presented HIV-induced IL-10, whereas those exposed to solid needles and to digital puncture did not, suggesting a relationship between infectious load and IL-10. Although occupational exposure to HIV leads to a low rate of seroconversion, these individuals can develop an antigen-specific immune response characterized in our study by induction of IL-10 in PBMC in vitro

HIV-1 subtypes among intravenous drug users from two neighboring cities in São Paulo State, Brazil

In order to assess the molecular epidemiology of HIV-1 in two neighboring cities located near the epicenter of the HIV-1 epidemics in Brazil (Santos and São Paulo), we investigated 83 HIV-1 strains obtained from samples collected in 1995 from intravenous drug users. The V3 through V5 region of the envelope of gp 120 was analyzed by heteroduplex mobility analysis. Of the 95 samples, 12 (12.6 percent) were PCR negative (6 samples from each group); low DNA concentration was the reason for non-amplification in half of these cases. Of the 42 typed cases from São Paulo, 34 (81 percent, 95 percent confidence limits 74.9 to 87.0 percent) were B and 8 (19 percent, 95 percent confidence limits 12.9 to 25.0 percent) were F, whereas of the 41 typed cases from Santos, 39 (95 percent, 95 percent confidence limits 91.6 to 98.4 percent) were B and 2 (5 percent, 95 percent confidence limits 1.6 to 8.4 percent) were C. We therefore confirm the relationship between clade F and intravenous drug use in São Paulo, and the presence of clade C in Santos. The fact that different genetic subtypes of HIV-1 are co-circulating indicates a need for continuous surveillance for these subtypes as well as for recombinant viruses in Brazil

Accuracy of replication in the polymerase chain reaction. Comparison between Thermotoga maritima DNA polymerase and Thermus aquaticus DNA polymerase

For certain applications of the polymerase chain reaction (PCR), it may be necessary to consider the accuracy of replication. The breakthrough that made PCR user friendly was the commercialization of Thermus aquaticus (Taq) DNA polymerase, an enzyme that would survive the high temperatures needed for DNA denaturation. The development of enzymes with an inherent 3' to 5' exonuclease proofreading activity, lacking in Taq polymerase, would be an improvement when higher fidelity is needed. We used the forward mutation assay to compare the fidelity of Taq polymerase and Thermotoga maritima (ULTMATM) DNA polymerase, an enzyme that does have proofreading activity. We did not find significant differences in the fidelity of either enzyme, even when using optimal buffer conditions, thermal cycling parameters, and number of cycles (0.2 per cent and 0.13 per cent error rates for ULTMATM and Taq, respectively, after reading about 3,000 bases each). We conclude that for sequencing purposes there is no difference in using a DNA polymerase that contains an inherent 3' to 5' exonuclease activity for DNA amplification. Perhaps the specificity and fidelity of PCR are complex issues influenced by the nature of the target sequence, as well as by each PCR component.