The French national prospective cohort of patients co-infected with HIV and HCV (ANRS CO13 HEPAVIH): early findings, 2006-2010.

BACKGROUND: In France, it is estimated that 24% of HIV-infected patients are also infected with HCV. Longitudinal studies addressing clinical and public health questions related to HIV-HCV co-infection (HIV-HCV clinical progression and its determinants including genetic dimension, patients' experience with these two diseases and their treatments) are limited. The ANRS CO 13 HEPAVIH cohort was set up to explore these critical questions.To describe the cohort aims and organization, monitoring and data collection procedures, baseline characteristics, as well as follow-up findings to date. METHODS: Inclusion criteria in the cohort were: age > 18 years, HIV-1 infection, chronic hepatitis C virus (HCV) infection or sustained response to HCV treatment. A standardized medical questionnaire collecting socio-demographic, clinical, biological, therapeutic, histological, ultrasound and endoscopic data is administered at enrollment, then every six months for cirrhotic patients or yearly for non-cirrhotic patients. Also, a self-administered questionnaire documenting socio-behavioral data and adherence to HIV and/or HCV treatments is administered at enrollment and yearly thereafter. RESULTS: A total of 1,175 patients were included from January 2006 to December 2008. Their median age at enrollment was 45 years and 70.2% were male. The median CD4 cell count was 442 (IQR: 304-633) cells/µl and HIV RNA plasma viral load was undetectable in 68.8%. Most participants (71.6%) were on HAART. Among the 1,048 HIV-HCV chronically co-infected patients, HCV genotype 1 was predominant (56%) and cirrhosis was present in 25%. As of January, 2010, after a median follow-up of 16.7 months (IQR: 11.3-25.3), 13 new cases of decompensated cirrhosis, nine hepatocellular carcinomas and 20 HCV-related deaths were reported, resulting in a cumulative HCV-related severe event rate of 1.9/100 person-years (95% CI: 1.3-2.5). The rate of HCV-related severe events was higher in cirrhotic patients and those with a low CD4 cells count, but did not differ according to sex, age, alcohol consumption, CDC clinical stage or HCV status. CONCLUSION: The ANRS CO 13 HEPAVIH is a nation-wide cohort using a large network of HIV treatment, infectious diseases and internal medicine clinics in France, and thus is highly representative of the French population living with these two viruses and in care.

Prototype protein assembly as scaffold for time-resolved fluoroimmuno assays.

Turnip yellow mosaic virus (TYMV) is an icosahedral plant virus with an average diameter of 28 nm and can be isolated in gram quantities from turnip or Chinese cabbage inexpensively. In this study, it was selected as a prototype bionanoparticle for time-resolved fluoroimmuno assay (TRFIA). Two types of reactive amino acid residues were employed to anchor luminescent terbium complexes and biotin groups based on orthogonal chemical reactions. While terbium complexes were used as luminescent signaling groups, biotin motifs acted as a model ligand for protein binding. The bioconjugation results were confirmed by MS and Western blot analysis. Steady-state and time-resolved luminescence study of the dual-modified viruses demonstrated that the spectroscopic properties of the Tb complex are unperturbed by the labeling procedure. The dual-modified particle was probed by fluorescence resonance energy transfer (FRET) experiments using avidin labeled with an Alexa488 fluorophore, which bound to the biotin on the surface of the particle, as an energy acceptor, and terbium complexes as an energy donor. The emission and excitation spectra of the dual-labeled TYMV particle displayed residual virus fluorescence and Tb luminescence upon ligand-centered excitation. The Tb luminescence lifetime was 1.62 ms and could be effectively fitted with a single-exponential behavior. In the TRFIA, an efficient transfer of 66% was observed, and the calculation using the Förster radius of 41 A allowed for an estimation of the average donor-acceptor distance of 36 A. Our studies show that the two reactive sites can communicate with each other on the surface of a nanoscale biological assembly. In particular, the ligand-receptor binding (biotin and avidin in this paper) was not interfered with when anchored to the surface of TYMV. Therefore, as a prototype of polyvalent bionanoparticles, TYMV can be used as scaffold for sensor development with TRFIA.