Comparative evaluation of molecular methods for the quantitative measure of torquetenovirus (TTV) viremia, the new surrogate marker of immune competence
Background Torquetenovirus (TTV) viremia is emerging as a promising tool to assess functional immune competence, to predict posttransplant immune-related complications, and eventually to customize immunosuppression. Methods In this study, 327 blood samples were tested using two real-time PCR (rtPCR) assays both targeted to the untranslated region of the TTV genome. The first assay was an in-house rtPCR developed by our group, the second one was the recently marketed TTV R-GENE assay. Results In the validation study, the TTV R-GENE showed good performances in precision and reproducibility, and sensitivity as low as 12 TTV DNA copies/mL, like previously reported for the in-house rtPCR. The Bl…
Assessment of prevalence and load of torquetenovirus viraemia in a large cohort of healthy blood donors.
OBJECTIVES: Torquetenovirus (TTV) is an emerging marker of functional immune competence with the potential to predict transplant-related adverse events. A large-scale epidemiological study was performed to understand how basal values vary in healthy individuals according to age and gender.; METHODS: We tested plasma from 1017 healthy blood donors aged 18-69years. The presence and load of TTV were determined by a real-time PCR assay. A sub-cohort of 384 donors was tested for anti-cytomegalovirus IgG antibodies, and 100 participants were also tested for TTV viraemia on a paired whole blood sample.; RESULTS: The overall prevalence of TTV was 65% (657/1017) with a mean (±SD) growth of 5±4% ever…
Evaluation of humoral and cellular response to four vaccines against COVID-19 in different age groups: A longitudinal study
To date there has been limited head-to-head evaluation of immune responses to different types of COVID-19 vaccines. A real-world population-based longitudinal study was designed with the aim to define the magnitude and duration of immunity induced by each of four different COVID-19 vaccines available in Italy at the time of this study. Overall, 2497 individuals were enrolled at time of their first vaccination (T0). Vaccine-specific antibody responses induced over time by Comirnaty, Spikevax, Vaxzevria, Janssen Ad26.COV2.S and heterologous vaccination were compared up to six months after immunization. On a subset of Comirnaty vaccinees, serology data were correlated with the ability to neutr…
Human OX40 tunes the function of regulatory T cells in tumor and nontumor areas of hepatitis C virus-infected liver tissue.
International audience; Regulatory T cells (Tregs) can be considered as a mixed population of distinct subsets, endowed with a diverse extent and quality of adaptation to microenvironmental signals. Here, we uncovered an opposite distribution of Treg expansion, phenotype, and plasticity in different microenvironments in the same organ (liver) derived from patients with chronic hepatitis C: On the one side, cirrhotic and tumor fragments were moderately and highly infiltrated by Tregs, respectively, expressing OX40 and a T-bet high IFN-c – " T-helper (Th)1-suppressing " phenotype; on the other side, noncirrhotic liver specimens contained low frequencies of Tregs that expressed low levels of O…
Candida blood stream infections observed between 2011 and 2016 in a large Italian University Hospital: A time-based retrospective analysis on epidemiology, biofilm production, antifungal agents consumption and drug-susceptibility
Candida bloodstream infection (BSI) represents a growing infective problem frequently associated to biofilm production due to the utilization of intravascular devices. Candida species distribution (n = 612 strains), their biofilm production and hospital antifungal drug consumption were evaluated in different wards of a tertiary care academic hospital in Italy during the years 2011–2016. In the considered time window, an increasing number of Candida BSI (p = 0.005) and of biofilm producing strains were observed (p<0.0001). Although C. albicans was the species more frequently isolated in BSI with a major biofilm production, an increased involvement of non-albicans species was reported, partic…
Early Post-Transplant Torquetenovirus Viremia Predicts Cytomegalovirus Reactivations In Solid Organ Transplant Recipients.
AbstractMonitoring the human virome has been recently suggested as a promising and novel area of research for identifying new biomarkers which would help physicians in the management of transplant patients. Imbalance of the immune system in transplant recipients has a significant impact on replication of Torquetenovirus (TTV), the most representative and abundant virus of human virome. TTV kinetic was studied by real-time PCR in 280 liver or kidney transplant recipients who underwent different drug regimens to maintain immunosuppression. During one-year post-transplant follow-up, TTV viremia fluctuated irrespective of transplanted organ type but consistent with the immunosuppression regimen…