Risk of transmission of human immunodeficiency virus (HIV) by heat-treated factor VIII concentrates in patients with severe hemophilia A

Deconvoluting the composition of low-frequency hepatitis C viral quasispecies: comparison of genotypes and NS3 resistance-associated variants between HCV/HIV coinfected hemophiliacs and HCV monoinfected patients in Japan

Pre-existing low-frequency resistance-associated variants (RAVs) may jeopardize successful sustained virological responses (SVR) to HCV treatment with direct-acting antivirals (DAAs). However, the potential impact of low-frequency (∼0.1%) mutations, concatenated mutations (haplotypes), and their association with genotypes (Gts) on the treatment outcome has not yet been elucidated, most probably owing to the difficulty in detecting pre-existing minor haplotypes with sufficient length and accuracy. Herein, we characterize a methodological framework based on Illumina MiSeq next-generation sequencing (NGS) coupled with bioinformatics of quasispecies reconstruction (QSR) to realize highly accurate variant calling and genotype-haplotype detection. The core-to-NS3 protease coding sequences in 10 HCV monoinfected patients, 5 of whom had a history of blood transfusion, and 11 HCV/HIV coinfected patients with hemophilia, were studied. Simulation experiments showed that, for minor variants constituting more than 1%, our framework achieved a positive predictive value (PPV) of 100% and sensitivities of 91.7–100% for genotyping and 80.6% for RAV screening. Genotyping analysis indicated the prevalence of dominant Gt1a infection in coinfected patients (6/11 vs 0/10, p = 0.01). For clinical samples, minor genotype overlapping infection was prevalent in HCV/HIV coinfected hemophiliacs (10/11) and patients who experienced whole-blood transfusion (4/5) but none in patients without exposure to blood (0/5). As for RAV screening, the Q80K/R and S122K/R variants were particularly prevalent among minor RAVs observed, detected in 12/21 and 6/21 cases, respectively. Q80K was detected only in coinfected patients, whereas Q80R was predominantly detected in monoinfected patients (1/11 vs 7/10, p < 0.01). Multivariate interdependence analysis revealed the previously unrecognized prevalence of Gt1b-Q80K, in HCV/HIV coinfected hemophiliacs [Odds ratio = 13.4 (3.48–51.9), p < 0.01]. Our study revealed the distinct characteristics of viral quasispecies between the subgroups specified above and the feasibility of NGS and QSR-based genetic deconvolution of pre-existing minor Gts, RAVs, and their interrelationships.

Sindbis virus as a tool for quality control of viral inactivation of heated and chemically treated plasma-derived products

Regulatory guidelines for production of plasma-derived products emphasize the need to document methods of viral inactivation and demonstrate the effectiveness of screening methods. Therefore, it is important to evaluate the kinetics of such processes. Togaviridae family virions may be considered as good tools for quality control of haemoderivatives, if they possess large amounts of cholesterol and saturated lipids and high structural lipid/protein ratio in their envelope composition, which give more resistance to classical treatments. The purpose of this study was to evaluate the efficiency of solvent-detergent and heat treatments adopted during the human haemoderivatives processment. Sindbis virus was used as a model for inactivation of enveloped viruses. Semi-processed human factor VIII (FVIII) product experimentally contaminated with Sindbis virus was used to test a solvent-detergent treatment with tri-N-butyl-phosphate (TNBP) and Tween 80. To evaluate thermal inactivation kinetics, lyophilized, and reconstituted samples of Sindbis virus-containing FVIII were incubated up to 30 h at 60 degrees C. The results showed that treatment with TNBP and Tween 80 reduced the infectivity of virus-contaminated FVIII in > or =5.5 log(10) and heat treatment was effective in all samples, although FVIII concentrate had reduced the rate of viral inactivation during a brief period of time.