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Background. Torquetenovirus (TTV) is a small DNA virus constituting the human virome. High levels of TTV-DNA have been shown to be associated with immunosuppression and inflammatory chronic disorders. Aim. To assess the possible association between the salivary viral load of TTV-DNA in patients hospitalised due to COVID-19 and disease severity. Methods. Saliva samples collected from 176 patients infected with SARS-CoV-2 were used to investigate the presence of SARS-CoV-2 and TTV-DNA by use of real-time RT-PCR. Results. The majority of patients were male with severe COVID-19. Presence of SARS-CoV-2 was observed in the saliva of 64.77% of patients, showing TTV-DNA in 55.68% of them. Patients with impaired clinical conditions (p < 0.001), which evolved to death (p = 0.003), showed a higher prevalence of TTV-DNA. The median viral load in patients with severe condition was 4.99 log10 copies/mL, in which those who were discharged and those evolving to death had values of 3.96 log10 copies/mL and 6.27 log10 copies/mL, respectively. A statistically significant association was found between the distribution of TTV-DNA viral load in saliva samples and severity of COVID-19 (p = 0.004) and disease outcomes (p < 0.001). Conclusions. These results indicate that TTV-DNA in saliva could be a useful biomarker of COVID-19 severity and prognosis. [ABSTRACT FROM AUTHOR]

Several reports have proposed that the viral load of torque teno virus (TTV) in plasma is a biomarker of immune function in solid organ transplantation (SOT) and in allogeneic hematopoietic stem cell transplantation. Additionally, for the latter one, TTV-DNA quantification in saliva has also been suggested. to investigate the correlation between the TTV viral load and immune function in paired saliva and plasma samples in patients on kidney transplantation. TTV-DNA viral load was quantified in paired samples of saliva and plasma from 71 patients before and a short-time after renal-transplantation by real-time PCR. The data obtained from 213 paired samples showed a slight consistency in the comparison between saliva and plasma, with prevalence of TTV-DNA being 58%, 52% and 60% in saliva samples and 60%, 73% and 90% in plasma samples before and at 15–20 and 45–60 days after transplantation, respectively. Additionally, a high TTV viral load was observed in plasma at 15–20 and 45–60 days after transplantation compared to that observed in saliva at the same time. Overall, monitoring TTV-DNA in saliva samples could be an additional fast non-invasive option to assess the immune functionality in SOT populations. [ABSTRACT FROM AUTHOR]

Cirrhosis-associated immune dysfunction is a complication of liver failure, and torque teno virus (TTV) has been pointed out as an endogenous marker of immune function. to investigate the TTV viral load in the plasma and saliva of cirrhotic individuals and correlate it with clinical characteristics. clinical data, plasma, and saliva were collected from 72 cirrhotic patients. they were predominantly male (n=51; 70.8%), with a median age of 57 years old and the median value of MELD was 15. 59,7% of the patients presented decompensated cirrhosis and 47.2% had alterations in the white blood series. TTV was identified in 28 specimens of plasma (38.8%) and 67 specimens of saliva (93.0%), with median values of TTV copies/mL of 90.6 in plasma and 245.14 in saliva. All the patients were positive for TTV in plasma and saliva, both fluids having a moderately positive correlation for the presence of TTV (Spearman's correlation coefficient = 0.576; P = 0.001). There was no correlation between TTV viral load, either in plasma or in saliva, and any of the variables studied (P > 0.05). There was no correlation between TTV viral load and clinical parameters. [ABSTRACT FROM AUTHOR]

Introduction: In Brazil, various isolates of rabies virus (RABV) show antigenic profiles distinct from those established by the reduced panel of eight monoclonal antibodies (MAbs) determined by the Centers for Disease Control and Prevention (CDC), utilized for the antigenic characterization of RABV in the Americas. The objective of this study was to produce MAbs from RABV isolates from insectivorous bats with an antigenic profile incompatible with the pre-established one. Methodology: An isolate of RABV from the species Eptesicus furinalis that showed an antigenic profile incompatible with the panel utilized was selected. Hybridomas were produced utilizing the popliteal lymph nodes of mice immunized with ribonucleoproteins purified from the isolate. Results: Two MAbs-producing clones were obtained, BR/IP1-3A7 and BR/IP2-4E10. Fifty-seven isolates of RABV from different species of animals and different regions of Brazil were analyzed utilizing the MAbs obtained. In the analysis of 23 RABV isolates from nonhematophagous bats, the MAbs cross-reacted with ten isolates, of which four were of the species Nyctinomops laticaudatus, one of the species Eptesicus furinalis, and five of the genus Artibeus. Of the nine isolates of non-hematophagous isolates that displayed an incompatible profile analyzed, characteristic of insectivorous bats, BR/IP1-3A7 reacted with five (55.55%) and BR/IP2-4E10 with four (44.44%). Conclusions: The MAbs obtained were able to recognize epitopes common between the three genera, Artibeus, Eptesicus, and Nyctinomops, thereby allowing the antigenic characterization of RABV isolates in Brazil. [ABSTRACT FROM AUTHOR]

Introduction: Torque teno virus (TTV) has been pointed as an endogenous marker of immune function, the objective of this study was to investigate the TTV viral load in plasma and saliva of cirrhotic individuals and correlate it with clinical characteristics., Methods: Blood, saliva, clinical data from records and laboratory tests were collected from 72 cirrhotic patients. Plasma and saliva were submitted to real-time polymerase chain reaction for quantification of TTV viral load., Results: The majority of the patients presented decompensated cirrhosis (59.7%) and 47.2% had alterations in the white blood series. TTV was identified in 28 specimens of plasma (38.8%) and in 67 specimens of saliva (93.0%), with median values of TTV copies/mL of 90.6 in plasma and 245.14 in saliva. All the patients who were positive for TTV in plasma were also positive in saliva, with both fluids having a moderately positive correlation for the presence of TTV. There was no correlation between TTV viral load, either in plasma or in saliva, and any of the variables studied., Conclusion: TTV is more frequently found and in greater amount in the saliva than in the plasma of cirrhotic patients. There was no correlation between TTV viral load and clinical parameters., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Falabello de Luca, Marinho, Franco, Tenório, Andrade, Batista, Mamana, Tozetto-Mendoza, Pérez Sayáns, Braz-Silva and Ortega.)

Background: Several reports have proposed that the viral load of torque teno virus (TTV) in plasma is a biomarker of immune function in solid organ transplantation (SOT) and in allogeneic hematopoietic stem cell transplantation. Additionally, for the latter one, TTV-DNA quantification in saliva has also been suggested., Aim: to investigate the correlation between the TTV viral load and immune function in paired saliva and plasma samples in patients on kidney transplantation., Materials and Methods: TTV-DNA viral load was quantified in paired samples of saliva and plasma from 71 patients before and a short-time after renal-transplantation by real-time PCR., Results: The data obtained from 213 paired samples showed a slight consistency in the comparison between saliva and plasma, with prevalence of TTV-DNA being 58%, 52% and 60% in saliva samples and 60%, 73% and 90% in plasma samples before and at 15-20 and 45-60 days after transplantation, respectively. Additionally, a high TTV viral load was observed in plasma at 15-20 and 45-60 days after transplantation compared to that observed in saliva at the same time., Conclusions: Overall, monitoring TTV-DNA in saliva samples could be an additional fast non-invasive option to assess the immune functionality in SOT populations., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Objective: To evaluate the humoral immune response to the pre-exposure schedule of human rabies vaccination through intradermal and intramuscular routes, as well as the need for serological monitoring., Methods: A randomized and controlled intervention study was carried out in São Paulo, Southeastern Brazil, from 2004-2005. There were 149 volunteers, of which 127 completed the vaccination schedule (65 intradermal and 62 intramuscular) and underwent humoral immune response evaluation at ten, 90 and 180 days post-vaccination. Two outcomes were considered for comparing the two routes of administration: the geometric average of neutralizing antibody titers and the proportion of individuals with satisfactory titers (> 0.5 IU/mL) at each evaluation point. The association of the humoral immune response with anthropometric and demographic data was analyzed through a normal distribution test and a chi-square test with a Yates correction. After completion of the vaccination schedule, the proportion of seropositive results was compared by the Kruskall Wallis test, and the average titers were compared by variance analysis., Results: the average antibody titers were higher in patients who were vaccinated intramuscularly. The percentage of volunteers with satisfactory titers (> 0.5% IU/mL) decreased over time in both groups. However, in the group vaccinated intradermally the rate of satisfactory titers on day 180 ranged from 20% to 25%, while the intramuscular route varied from 63% to 65%. An association between the humoral immune response and the demographic and anthropometric variables was not observed., Conclusions: Serology after the third dose can be considered unnecessary in unexposed patients, since 97% and 100% of volunteers respectively vaccinated by the intradermal and intramuscular route presented satisfactory antibody levels (> 0.5% IU/mL).