Overproduction of IL-6 and Type-I IFN in a Lethal Case of Chikungunya Virus Infection in an Elderly Man During the 2017 Italian Outbreak.

Chikungunya fever is caused by Chikungunya virus (CHIKV) and is generally considered a self-limiting disease. However, severe clinical presentations with a high mortality rate have been reported in association with underlying medical conditions. This study reports the molecular characterization of the virus and an abnormal pattern of circulating cytokines in a unique lethal CHIKV case during the 2017 outbreak in Italy, which involved an elderly patient with underlying cardiac disease.

Long-Term Follow-Up of Acute Hepatitis B: New Insights in Its Natural History and Implications for Antiviral Treatment.

Acute hepatitis B infection (AHB) is still a common viral acute hepatitis worldwide. As vaccination, antiviral treatment, and immigration are bound to affect the epidemiological landscape of HBV infections, and some of its aspects need to be investigated: (1) the circulation of vaccine escape mutants and of primary drug resistant strains; (2) the change in HBV genotype prevalence; and (3) the clinical implications of AHB and the probability of chronification. The serological, virological, and clinical parameters of 75 patients, acutely infected by HBV, were gathered for a retrospective study.

Prolonged detection of dengue virus RNA in the semen of a man returning from Thailand to Italy, January 2018.

This study reports the presence of dengue virus RNA in longitudinally collected semen samples of a previously healthy Caucasian man, returning to Italy from Thailand with primary dengue fever, up to 37 days post-symptom onset, when viraemia and viruria were undetectable. This finding, coupled with the evidence of dengue virus negative-strand RNA, an indirect marker of ongoing viral replication, in the cellular fraction of semen, indicates a need to further investigate possible sexual transmission.

Evolutionary trends of resistance mutational patterns of HBV reverse transcriptase over years (2002-2012) of different treatment regimens: The legacy of lamivudine/adefovir combination treatment.

Antiviral therapy has revolutionized treatment of chronic HBV infections. First generation compounds, lamivudine and adefovir, displayed a high rate of treatment failures, and have been replaced by more potent compounds with high genetic barrier to resistance. However, the evolution of the virus towards resistance due the use of first generation compounds may still provide useful information for a better management of current antivirals.

a statistical model based on serological parameters for predicting occult HBV infection: implications for organ/ blood donations.

The transmission of hepatitis B virus by donors with occult HBV infection (OBI) is a threat for blood transfusion and organ/tissue transplantation. The risk of carrying HBV DNA is currently not predictable by simple serologic markers, while HBV DNA testing is not universally deployed. This study evaluated an integrated serologic approach for assessing this risk.

Coexistence of HBsAg and HBsAb in a difficult-to-treat chronic hepatitis B: loss of HBsAg with entecavir plus tenofovir combination.

Background: Some reports have documented the coexistence of Hepatitis B surfage Antigen (HBsAg) and anti-HBsAg antibodies (HBsAb) in patients with chronic hepatitis B (CHB), often in the absence of amino acid substitutions in the HBsAg sequences of the Hepatitis B Virus (HBV) genome able to explain an immunological escape variant.HBV genome has a very compact coding organization, with four partially overlapping open reading frames (ORFs). Because the reverse transcriptase region (rt) of HBV polymerase overlaps the HBsAg ORF, it is possible that some mutations in the HBsAg region correspond to mutations in the rt ORF, conferring resistance to current antiviral therapies.

Slow response to entecavir treatment in treatment-naive HBV patients is conditioned by immune response rather than by the presence or selection of refractory variants.

Background: Entecavir is the drug of choice as first-line treatment for treatment-naive HBV patients. As a result of the high genetic barrier to resistance, treatment failure remains rare, but occurs within 3 years of initiation, suggesting that viral genetic characteristics may provide a fast lane to resistance. One of the main concerns is the long time to viral suppression observed in some (even treatment-naive) patients.

Combinatorial analysis and algorithms for quasispecies reconstruction using next-generation sequencing.

Background: Next-generation sequencing (NGS) offers a unique opportunity for high-throughput genomics and has potential to replace Sanger sequencing in many fields, including de-novo sequencing, re-sequencing, meta-genomics, and characterisation of infectious pathogens, such as viral quasispecies. Although methodologies and software for whole genome assembly and genome variation analysis have been developed and refined for NGS data, reconstructing a viral quasispecies using NGS data remains a challenge. This application would be useful for analysing intra-host evolutionary pathways in relation to immune responses and antiretroviral therapy exposures.

Effect of HIV co-infection on mutation patterns of HBV in patients with lamivudine-resistant chronic hepatitis B.

A retrospective review was performed comparing lamivudine-resistance mutation patterns between patients infected with hepatitis B virus (HBV) with or without human immunodeficiency virus (HIV) co-infection. Medical records that included a genotypic test of patients infected with HBV and treated with lamivudine as the only anti-HBV drug were reviewed. Pol gene mutations were assessed by direct sequencing of the reverse transcriptase fragment 125-213 aa.

A sensitive direct sequencing assay based on nested PCR for the detection of HBV polymerase and surface glycoprotein mutations.

Drug resistance is a crucial problem emerging frequently during treatment of hepatitis B, resulting in treatment failure and progression of liver damage. A direct sequencing method based on a nested PCR was established to detect mutations in samples with low viral load. Primers were designed to obtain an amplicon encompassing the A, B, C, D and E functional domains of HBV polymerase.

Use of massively parallel ultradeep pyrosequencing to characterize the genetic diversity of hepatitis B virus in drug-resistant and drug-naive patients and to detect minor variants in reverse transcriptase and hepatitis B S antigen.

Direct population sequencing and reverse hybridization (line probe assay [LiPA])-based methods are the most common methods for detecting hepatitis B virus (HBV) drug resistance mutations, although only mutations present in viral quasispecies with a prevalence of > or =20% can be detected by sequencing, and only known mutations are detected by LiPA. Massively parallel ultradeep pyrosequencing (UDPS; GS FLX platform) was used to analyze HBV quasispecies in reverse transcriptase (RT) and hepatitis B S antigen (HBsAg) from five drug-naive patients and eight drug-resistant patients. Eight primer pairs were used to obtain partially overlapping amplicons, covering the RT gene from codons 1 to 288 and the complete overlapping HBsAg sequence.

Selected RD1 peptides for active tuberculosis diagnosis: comparison of a gamma interferon whole-blood enzyme-linked immunosorbent assay and an enzyme-linked immunospot assay.

We recently set up a gamma interferon (IFN-gamma) enzyme-linked immunospot assay (ELISPOT), using selected early secreted antigenic target 6 (ESAT-6) peptides, that appears specific for active tuberculosis (A-TB). However, ELISPOT is difficult to automate. Thus, the objective of this study was to determine if the same selected peptides may be used in a technique more suitable for routine work in clinical laboratories, such as whole-blood enzyme-linked immunosorbent assay (WBE).

Use of a T cell-based assay for monitoring efficacy of antituberculosis therapy.

Monitoring the efficacy of antituberculosis therapy is crucial both for the individual patient and for better control of the spread of tuberculosis. We studied 18 patients with microbiologically confirmed tuberculosis, both at the time of diagnosis and 3 months after they started therapy, using an in vitro assay that detects T cell-mediated interferon- gamma response to selected peptides of Mycobacterium tuberculosis-specific early secretory antigenic target 6 (ESAT-6) protein. All patients had positive results at diagnosis; however, 3 months later, the response to ESAT-6 peptides was still detectable only in the 5 patients with microbiological isolation and/or absence of clinical improvement after treatment.

Inhibition of HIV-1 replication in monocyte-derived macrophages by Mycobacterium tuberculosis.

Controversial results have been obtained in studies of the effect of Mycobacterium tuberculosis on human immunodeficiency virus type 1 (HIV-1) replication in cells of the macrophage lineage. In the present study, monocyte-derived macrophages (MDMs), previously incubated for 2 days with heat-inactivated M. tuberculosis, were infected with HIV-1.

Identification of early secretory antigen target-6 epitopes for the immunodiagnosis of active tuberculosis.

The early secretory antigenic target (ESAT)-6 purified protein and peptides from Mycobacterium tuberculosis were evaluated as antigens for the immunodiagnosis of tuberculosis (TB). Because the control of TB requires improved diagnostic procedures, efforts have increased to identify Mycobacterium tuberculosis-specific epitopes for the immunodiagnosis of active TB and to discriminate between active and latent states of infection. Two multiepitopic peptides from ESAT-6 protein were selected by computational analysis.