T-cell-based gamma interferon (IFN-␥) release assays (IGRAs) using Mycobacterium tuberculosis-specific antigens have shown higher sensitivity and specificity than the routine tuberculin skin test (TST). However, the effects of Mycobacterium bovis BCG vaccination and anti-tuberculosis (TB) treatment on dynamic T-cell responses to M. tuberculosis-specific antigens in active TB cases have rarely been investigated in regions where TB is endemic. Eighty-nine patients with active pulmonary TB (ATB) and 57 healthy controls (HC) from China were recruited and tested by sputum smear and culture, TSTs, and IGRAs with M. tuberculosis-specific antigens ESAT-6 and CFP-10 (T-SPOT.TB) as well as purified protein derivative (PPD) stimulation. All 146 participants were screened by the T-SPOT.TB assay at recruitment. T-SPOT.TB-positive rates in ATB and HC groups were 87.6% (78/89) and 21.1% (12/57), respectively. Of 38 ATB patients who were both TST and T-SPOT.TB tested, the positive rates were 73.7% (28/38) and 94.7% (36/38), respectively (P ‫؍‬ 0.0215), and those in the HC group were 62.3% (33/53) and 18.9% (10/53), respectively (P < 0.0001). The T-SPOT.TB-positive rates declined during TB treatment and were 94.4% (51/54), 86.4% (19/22), and 61.5% (8/13) for ATB patients receiving 0-to 1-month, 1-to 3-month, and 3-to 6-month anti-TB treatment, respectively. The IGRA is a most promising test for both active TB and latent TB infection (LTBI) diagnosis due to the improvement of its specificity and convenience, especially in the Mycobacterium bovis BCG-vaccinated population. Furthermore, the T-SPOT.TB assay using ESAT-6 and CFP-10 in ATB patients during anti-TB treatment could serve as a potential predictor of therapeutic efficacy.

Objective. The rheumatoid synovium displays characteristics of Toll-like receptor (TLR) activation and antiviral gene expression, including production of RANTES and interferon-␤ (IFN␤). The mechanism of this activation in rheumatoid synovial tissue is unknown. This study was designed to investigate the role of the IKK-related kinase IKK and IFN regulatory factor 3 (IRF-3) in the activation of antiviral genes in rheumatoid arthritis (RA). Methods. Kinase assay and immunostaining were performed on synovial tissue. Dominant-negative (DN) IKK adenoviral infection of human fibroblast-like synoviocytes (FLS) was followed by poly(I-C

Background/Aims: Circular RNAs (circRNAs), a new class of regulators of gene expression, are involved in diverse physiological and pathogenic processes. However, their role in cellular responses to virus infection is yet unclear. Methods: A human lung fibroblast cell line was infected or mock infected by herpes simplex virus 1 (HSV-1). Deep RNA sequencing was used to profile the global changes in circRNAs, genes, and miRNAs following HSV-1 infection. Altered circRNAs, genes, and miRNAs were validated using quantitative reverse transcription polymerase chain reaction (RT-qPCR). An integration analysis of circRNAs, genes, and miRNAs was applied to investigate the putative function of the dysregulated circRNAs. Results: A total of 536 circRNAs, 3,885 genes, and 207 miRNAs were significantly dysregulated after HSV-1 infection. An integration analysis of circRNAs, genes, and miRNAs revealed the alleged involvement of dysregulated circRNAs in cellular responses to HSV-1 infection via the circRNA-miRNA-gene regulatory axis. These genes regulated by circRNAs were enriched to NOD-like receptor/JAK-STAT signaling pathway, and pathways of apoptosis, cell cycle progression, and cell death, all of which may be implicated in the viral pathogenesis and cellular immunity. Conclusions: These data present a comprehensive view for circRNAs induced by HSV-1 and their interplay with miRNAs and genes during HSV-1 infection, thus offering new insights into the mechanisms of interactions between HSV-1 and the host.

Background and Aim: Daclatasvir plus asunaprevir has demonstrated efficacy and safety in patients with chronic hepatitis C virus genotype 1b infection. This study focused on evaluating daclatasvir plus asunaprevir in interferon (±ribavirin)-ineligible or -intolerant Asian patients with genotype 1b infection from mainland China, Korea, and Taiwan. Methods: Interferon (±ribavirin)-ineligible and -intolerant patients with genotype 1b infection received daclatasvir 60 mg tablets once daily plus asunaprevir 100 mg soft capsules twice daily for 24 weeks. The primary endpoint was sustained virologic response at posttreatment week 24 (SVR24). Results: Of the 159 patients treated, 89.3% were Chinese, 65.4% were female, and 73.6% were interferon-intolerant. Cirrhosis was present in 32.7% of patients, and 40.3% had IL28B non-CC genotypes. SVR24 was achieved by 145/159 (91.2%) patients (100% concordance with SVR12) and was similarly high in cirrhotic patients (47/52, 90.4%). SVR24 was higher in patients without baseline NS5A (L31M or Y93H) resistance-associated variants (RAVs) (137/139, 98.6%), including those with cirrhosis (43/44, 97.7%). Prevalence of baseline NS5A RAVs was low (19/159, 11.9%), particularly in mainland China (10/127, 7.9%). One death (0.6%), five serious adverse events (3.1%), and three grade 4 laboratory abnormalities (1.9%) occurred on treatment; none were considered related to study drugs. Two patients (1.3%) discontinued because of adverse events. Treatment was generally well tolerated regardless of cirrhosis status. Conclusions: Daclatasvir plus asunaprevir achieved a SVR24 rate of 91.2%, rising to 98.6% in patients without baseline NS5A RAVs, and was generally well tolerated in interferon (±ribavirin)-ineligible or -intolerant patients with genotype 1b infection from mainland China, Korea, and Taiwan.

Circular RNAs (circRNAs), identified as a class of widely expressed endogenous regulatory RNAs, are involved in diverse physiological and pathological processes. However, their role in viral pathogenesis and cellular antiviral response remains unexplored. In this study, a potent DNA tumor virus, simian virus 40 (SV40), was used as a model to investigate the viral influences on cellular circRNA transcriptome.Using RNA-seq, 15,241 putative circRNAs were identified de novo from 5,057 parental genes in monkey kidney–derived Vero cells. The expression of selected circRNAs was confirmed by reverse transcription-polymerase chain reaction and Sanger sequencing. Further analysis showed that most circRNAs comprised multiple exons, and most parental genes produced multiple circRNA isoforms. A total of 134 significantly dysregulated circRNAs, including 103 upregulated and 31 downregulated circRNAs, were found after SV40 infection. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that various cancer-related pathways, including p53 and Wnt pathway, could be affected by SV40 infection via the alteration of the circRNA hosting genes. Moreover, diverse cellular immune pathways, including Toll-like receptor pathway and Janus kinase–signal transducer and activator of transcription pathway, could also be affected by SV40 infection. An integrated circRNA-miRNA-gene analysis suggested the putative function of circRNAs as cellular and viral miRNA decoys to indirectly regulate the gene expression during SV40 infection. This study presented the first comprehensive expression and functional profile of circRNAs in response to SV40 infection, thus providing new insights into the mechanisms of viral pathogenesis and cellular immune response.

Mycobacterium tuberculosis KatG enzyme functions both as catalase for removing hydrogen peroxide (H 2 O 2 ) and as peroxidase for oxidating isoniazid (INH) to active form of anti-tuberculosis drug. Although mutations in M. tuberculosis KatG confer INH resistance in tuberculous patients, structural bases for INH-resistant mutations in the KatG gene remains poorly understood. Here, three M. tuberculosis KatG mutants bearing Arg418→ Gln, Ser315 → Thr, or Trp321 → Gly replacement were assessed for changes in catalase-peroxidase activities and possible structure bases relevant to such changes. These three M. tuberculosis KatG mutants exhibited a marked impairment or loss of catalase-peroxidase activities. The possible structural bases for the mutant-induced loss of enzyme activities were then analyzed using a three-dimensional model of M. tuberculosis KatG protein constructed on the basis of the crystal structure of the catalase-peroxidase from Burkholderia pseudomallei. The model suggests that three M. tuberculosis KatG mutants bearing Arg418 → Gln, Ser315 → Thr, or Trp321 → Gly replacement affect enzyme activities by different mechanisms, although each of them impacts consequently on a heme-associated structure, the putative oxidative site. Moreover, in addition to the widely accepted substrate-binding site, M. tuberculosis KatG may bear another H 2 O 2 binding site. This H 2 O 2 binding site appears to interact with the catalytic site by a possible electron-transfer chain, a Met255-Tyr229-Trp107 triad conserved in many catalaseperoxidases. The Ser315 → Thr mutant may have direct effect on the catalytic site by interfering with electron transfer in addition to the previously proposed mechanism of steric constraint.

BackgroundDengue is the most common mosquito-borne infection worldwide and a serious threat to global public health. Sporadic dengue virus serotype 2 (DENV-2) imported cases from Myanmar have been documented almost every year in Yunnan Province of China since 2005. However, the complete genome sequences of DENV-2 isolates imported from Myanmar are not available.MethodsThe full-length genome of the DENV-2 strain (YNPE2), isolated from an imported case from Myanmar in 2013, was identified by the next-generation sequencing. The extreme ends of the viral genome were validated by 5′/3′ RACE and Sanger sequencing. Furthermore, phylogenetic, recombination and selection pressure analyses were conducted for the molecular characterization of YNPE2 strain.ResultsWhole-genome sequencing revealed that the full-length sequence of YNPE2 strain was 10,724 bases, with an open reading frame encoding for 3391 amino acids. The YNPE2 strain had 99.0% nucleotide identity and 99.8% amino acid identity with two closely related strains, ThD2_0078_01 strain (DQ181797) and DENV-2/TH/BID-V2157/200 strain (FJ639832). The phylogenetic analysis suggested that the YNPE2 strain belonged to Asian I genotype and was likely derived from Thailand strain (DQ181797). Moreover, selection pressure analysis revealed two amino acid sites of the NS4B and NS5 proteins, with important evidence of positive selection.ConclusionThis study revealed the first complete genome sequence and molecular characterization of a DENV-2 strain (YNPE2) isolated from an imported case from Myanmar, thus providing a valuable reference genome source for future surveillance, epidemiology and vaccine development of DENV-2 virus in Yunnan, China.Electronic supplementary materialThe online version of this article (10.1186/s12985-018-1043-2) contains supplementary material, which is available to authorized users.

No abstract