Torquetenovirus viremia for early prediction of graft rejection after kidney transplantation.

OBJECTIVES: New biomarkers reflecting the degree of immunosuppression in transplant recipients are needed to provide an optimal personalized balance between rejection and infection risks. METHODS: For this purpose, we investigated TTV viremia dynamics in 66 kidney transplant recipients followed up for two years after transplantation, in relation to BK virus infection and graft rejection. RESULTS: After transplantation, TTV viremia rose by ≥2 log10 copies/mL from baseline to month 3, then declined by ≥1 log10 copies/mL thereafter. Higher TTV viremia was associated with recipients of a deceased donor, a lower count of CD8+ T cells and a higher BKV viremia. Importantly, TTV loads were significantly lower in KTR who would later display graft rejection; indeed, patients with TTV viremia lower than 3.4 log10 copies/mL at transplantation or lower than 4.2 log10 copies/mL at month 1 had a higher risk of developing graft rejection in the two following years (hazard ratio (HR) at D0 = 7.30, p = 0.0007 and HR at M1 = 6.16, p = 0.001). CONCLUSIONS: TTV viremia measurement at early times post transplantation predicts graft rejection and would represent a useful tool to improve kidney transplant monitoring.

[Study of hepatitis C virus leukotropism by characterization of viral quasispecies in the liver transplantation setting]. / Etude du leucotropisme du virus de l'hépatite C par analyse des quasi-espèces virales dans le contexte de la transplantation hépatique.

Besides hepatocytes, representing the main replication site of hepatitis C virus, peripheral blood mononuclear cells also represent a crucial target for viral infection. Hepatitis C virus compartmentalization (i.e., non-random distribution) of viral variants between plasma and peripheral blood mononuclear cells, more frequently observed in liver transplant patients compared to non-transplanted patients, makes liver transplantation an interesting model for the analysis of hepatitis C leukotropism. This article aims to present, firstly, in clinical and biological features arguing favour of hepatitis C virus infection leukotropism and, secondly, to review current knowledge about compartmentalization between plasma and peripheral blood mononuclear cells, especially in the liver transplantation setting.

[New lights on infectious mononucleosis]. / La mononucléose infectieuse (MNI) « revisitée ¼.

This review focuses on recent studies that shed new lights on infectious mononucleosis (IM). The major transmission of Epstein-Barr virus (EBV) via saliva is opposed to the possibility of sexual transmission of EBV in developed countries. Multiple infections with different LMP-1 EBV genotypes are frequently observed during IM but with unclear significance. The strict lymphotropism of the virus during primary EBV infection is questioned. Prolonged high EBV-load in saliva is clearly demonstrated during IM and could be explained by a different immune response in tonsil versus blood. Benign and severe IM are also explained by the variability of the immune response. Correlations between severity of IM and high viral load in blood are controversial. A relationship between IM and Hodgkin's disease is suggested by several epidemiological studies. Despite potential new antiviral targets and preliminary human vaccine trials, the lack of curative or preventive treatment against IM is pointed out.

[Recurrence of hepatitis C virus (HCV) infection after liver transplantation for HCV-related disease: host factors and viral factors implicated in the occurrence and the severity of HCV recurrence]. / Récurrence de l'infection par le virus de l'hépatite C (VHC) après transplantation du foie pour hépatopathie due au VHC: facteurs liés à l'hôte et facteurs viraux impliqués dans la survenue et la gravité de la récurrence de l'hépatite virale C.

Cirrhosis due to chronic infection by hepatitis C virus (HCV), associated or not to a primary hepatocarcinoma, has become the first indication of liver transplantation. Graft reinfection by HCV is considered to be systematic while its prognosis is variable from one patient to another. A better knowledge of factors implicated in the occurrence and severity of hepatitis C recurrence is crucial in order to make optimal patients' monitoring. This article aims to present available data in this field, clarifying the role of viral factors (viral load, genotype, evolution of viral quasispecies) and host-related factors (immune response) which could take part in the development of hepatitis C recurrence.

Comparison of serum hepatitis C virus (HCV) RNA and core antigen levels in patients coinfected with human immunodeficiency virus and HCV and treated with interferon plus ribavirin.

Trak-C (Ortho-Clinical Diagnostics) is an enzyme-linked immunosorbent assay-based method capable of quantifying hepatitis C virus (HCV) core antigen (CA) in serum and could be an alternative to molecular detection and quantification of HCV RNA. We have evaluated the Trak-C assay in comparison with an HCV RNA quantitative assay (Versant HCV v3.0; Bayer Diagnostics) in the follow-up of 348 treated, human immunodeficiency virus (HIV)/HCV-coinfected patients included in the ANRS HC02 RIBAVIC trial. ANRS HC02 RIBAVIC is a therapeutic, multicenter, randomized protocol comparing the efficacy of alpha interferon 2b (IFN-alpha2b) (3 million units three times a week)-ribavirin (800 mg/day) to that of pegylated IFN-alpha2b (1.5 mug/kg of body weight/week)-ribavirin (800 mg/day) during 48 weeks of treatment of HIV/HCV-coinfected patients naïve to HCV treatment. Patients were assessed for virological analysis at day 0 and weeks 4, 12, 24, 48, and 72. Correlation of HCV RNA and HCV CA at the initiation of treatment was excellent (r = 0.92). HCV RNA and CA kinetics were similar during follow-up of HCV treatment from day 0 to week 72 whatever the group of response and genotype. The positive and negative predictive values of response to the treatment at week 4 were 59 and 94%, respectively, for HCV RNA load reduction of >2 log and 54 and 94%, respectively, for HCV CA below the threshold value (4.18 log(10) pg/ml . 10(4)). Trak-C, a new assay able to quantify CA in HIV/HCV-coinfected patients, correlates well with quantitative HCV RNA assays and is cheaper and easier to perform than molecular technology. HCV CA could be a valuable alternative test for therapeutic follow-up of coinfected patients treated with IFN plus ribavirin in developing countries.