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An increasing amount of evidence emphasizes the role of metabolic reprogramming in immune cells to fight infections. However, little is known about the regulation of metabolite transporters that facilitate and support metabolic demands. In this study, we found that the expression of equilibrative nucleoside transporter 3 (ENT3, encoded by solute carrier family 29 member 3, Slc29a3) is part of the innate immune response, which is rapidly upregulated upon pathogen invasion. The transcription of Slc29a3 is directly regulated by type I interferon‐induced signaling, demonstrating that this metabolite transporter is an interferon‐stimulated gene (ISG). Suprisingly, we unveil that several viruses, including SARS‐CoV‐2, require ENT3 to facilitate their entry into the cytoplasm. The removal or suppression of Slc29a3 expression is sufficient to significantly decrease viral replication in vitro and in vivo. Our study reveals that ENT3 is a pro‐viral ISG co‐opted by some viruses to gain a survival advantage. Synopsis: ENT3 is an IFN‐stimulated metabolite transporter in macrophages that facilitates viral genome release. Suppression of ENT3 expression is sufficient to decrease viral replication both in vitro and in vivo. ENT3 is a fast‐responding metabolite transporter upon pathogen insults.ENT3 is an interferon‐stimulated gene whose expression is regulated by the type I IFN‐IFNAR axis.Viruses have co‐evolved with the host and take advantage of ENT3 for their genome release and their replication. [ABSTRACT FROM AUTHOR]

To circumvent the devastating pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection, a humanized decoy antibody (ACE2‐Fc fusion protein) was designed to target the interaction between viral spike protein and its cellular receptor, angiotensin‐converting enzyme 2 (ACE2). First, we demonstrated that ACE2‐Fc could specifically abrogate virus replication by blocking the entry of SARS‐CoV‐2 spike‐expressing pseudotyped virus into both ACE2‐expressing lung cells and lung organoids. The impairment of viral entry was not affected by virus variants, since efficient inhibition was also observed in six SARS‐CoV‐2 clinical strains, including the D614G variants which have been shown to exhibit increased infectivity. The preservation of peptidase activity also enables ACE2‐Fc to reduce the angiotensin II‐mediated cytokine cascade. Furthermore, this Fc domain of ACE2‐Fc was shown to activate NK cell degranulation after co‐incubation with Spike‐expressing H1975 cells. These promising characteristics potentiate the therapeutic prospects of ACE2‐Fc as an effective treatment for COVID‐19. Synopsis: Currently, there is no effective strategy to fight against the COVID‐19 pandemic. We aim to design and develop a humanized decoy antibody to block SARS‐CoV‐2 infection. The ACE2‐Fc fusion protein can form a dimer that mimics a humanized antibody and specifically binds to the SARS‐CoV‐2 Spike protein.The ACE2‐Fc fusion protein abrogates virus replication by blocking SARS‐CoV‐2 entry in clinical isolates.The peptidase activity of ACE2‐Fc enables the decoy antibody to reduce angiotensin II‐mediated cytokine cascade.After binding to Spike‐expressing target cells, ACE2‐Fc activates degranulation of NK cells. [ABSTRACT FROM AUTHOR]

Background: Higher rates of hepatitis C virus (HCV) reinfection after viral clearance have been well described among HIV‐positive men who have sex with men (MSM) in Europe. The epidemiology of HCV reinfection, however, has rarely been investigated among HIV‐positive patients in Asia‐Pacific region. Methods: We retrospectively identified HIV‐positive patients with recent HCV infection who had cleared their primary infection, either spontaneously or via treatment, between January 2011 and May 2018. All included patients were observed until 31 March 2019. HCV reinfection was defined as recurrent HCV viraemia after achieving viral clearance with anti‐HCV treatment or after spontaneous clearance. Results: During the study period, 219 HIV‐positive patients (90.4% MSM) were diagnosed with recent HCV infection. Viral clearance with successful treatment was achieved in 108 patients (49.3%) and spontaneous clearance occurred in 20 (9.1%); of them, 18 (14.1%) acquired HCV reinfections, resulting in an incidence rate of 8.2 per 100 person‐years of follow‐up (95% CI 5.2‐13.1). With the adjusted Cox proportional hazards model, we found a higher reinfection risk in patients with syphilis (adjusted hazard ratio 10.3, 95% CI 1.4‐77.8, P = .023) compared to those without syphilis. HCV RNA testing, if performed only following syphilis and elevated aminotransferases, might miss 44.4% and 33.3% of HCV reinfections, respectively. Conclusions: Similar to the findings in Europe, we observed a high incidence of HCV reinfection among HIV‐positive Taiwanese with recent HCV infection, which was significantly associated with syphilis. To identify HCV reinfections, annual HCV RNA testing should be instituted instead of testing driven by symptoms, syphilis or elevated aminotransferases. [ABSTRACT FROM AUTHOR]

Background: Acute hepatitis C virus (HCV) infections have been increasingly reported among human immunodeficiency virus (HIV)‐positive men who have sex with men (MSM) in the Asia‐Pacific region. It remains unknown whether international network of HCV transmission has occurred in this region. Methods: HIV‐positive patients with acute HCV infection, defined as HCV seroconversion within a year or documented acute hepatitis with seroconversion, diagnosed in Hong Kong, Taipei and Tokyo during 2010‐2016 were included in this molecular epidemiology study. The NS5B region of the HCV genome (365 bp) was amplified using nested polymerase chain reaction and sequenced. Results: Of 234 HIV‐positive patients with acute HCV infection, all were male with 94% being MSM. At the diagnosis of acute HCV infection, 73.5% had concurrent sexually transmitted diseases and 88.0% were receiving combination antiretroviral therapy. The most prevalent HCV genotype was 3a, 2a and 1b in Hong Kong, Taipei and Tokyo respectively. Nine independent clusters belonging to five genotypes (1b, 2a, 2c, 3a and 6a) were identified, each of which occurred in one city without overlapping except for one 3a sequence from Taipei that was closely related genetically to the Hong Kong cluster. Conclusions: No international network of HCV transmission was identified among HIV–positive patients in the three Asia‐Pacific cities. The transmission dynamics of sexually acquired HCV differed by city, but the risk of intercity clustering should not be ignored. [ABSTRACT FROM AUTHOR]

Introduction: HIV infection impairs maintenance of immunological memory, yet few studies of HIV-positive adults receiving 7-valent pneumococcal conjugate vaccine (PCV7) have followed them beyond the first year. We determined and compared the durability of serological responses and the clinical outcomes of HIV-positive adults annually for five years following vaccination with one or two doses of PCV7. Methods: In this non-randomized clinical trial, 221 pneumococcal vaccine-naïve HIV-positive adults receiving one (n=109) or two doses four weeks apart (n=112) of PCV7 between 2008 and 2010 were longitudinally followed for evaluation of significant serological response and for episodes of pneumonia and invasive pneumococcal disease. Results: At the time of vaccination, the two groups were well matched for age, risk factors, combination antiretroviral therapy (cART) coverage, CD4 count and plasma HIV RNA load (PVL). At the end of five years, the CD4 counts for the one- and two-dose groups had increased from 407 and 406 to 550 and 592 cells/mL, respectively, and 82.4 and 81.6% of the participants had fully suppressed PVL. Significant immune responses to ≥2 serotypes persisted for 67.9 vs 78.6%, 64.2 vs 71.4%, 66.1 vs 71.4%, 57.8 vs 69.6% in the second, third, fourth and fifth years after one and two doses of PCV7 in the intention-to-treat analysis, respectively. In multivariate analysis, immunization with two doses of PCV7 (odds ratio (OR) 1.71, 95% confidence interval (CI) 1.10 to 2.65, p=0.016), concurrent cART (OR 2.16, 95% CI 1.16 to 4.00, p=0.015) and CD4 proliferation (OR 1.12, 95% CI 1.01 to 1.27, p=0.031) were predictive of persistent serological responses in the fifth year. Only one patient in the one-dose group had documented pneumococcal pneumonia (non-bacteraemic) and none had invasive pneumococcal disease in the 6.5 years of follow-up. Conclusions: One or two doses of PCV7 achieve durable seroprotective responses in HIV-treated participants; however, two doses may be more robust than one dose in a larger study population or in real-world populations with less cART coverage. [ABSTRACT FROM AUTHOR]

Background Allergic asthma is a globally respiratory inflammatory disease. Influenza virus is a respiratory pathogen that causes yearly epidemics and results in high rates of morbidity and mortality. Patients with allergic asthma had a more severe symptom and a higher mortality when they were infected with influenza virus. Hence, influenza vaccination is recommended for patients with asthma. Objectives We evaluated the efficacy and effects of influenza vaccination on allergic asthma in a mouse model. Methods Ovalbumin-immunized mice were inoculated with inactivated influenza virus A/Puerto Rico/8/34 (PR8) as vaccines and morbidity or mortality and allergic asthma features of these mice were analyzed. Results Mice inoculated with inactivated PR8 induced high levels of anti-PR8 IgG2a and upregulation of Toll-like receptor (TLR) 7. Vaccinated allergic mice were healthy when they were challenged with live influenza virus while none of non-vaccinated allergic mice survived. Furthermore, inactivated influenza virus vaccine induced neither extra airway inflammation nor asthma features such as IgE, airway hyper-reactivity, and eosinophilia in allergic mice. Particularly, decreased frequency of immune cell infiltrated airways and Th2 cytokines IL-4 and IL-6 production in the bronchoalveolar lavage fluid were noted in vaccinated allergic mice. These results suggested that inactivated influenza virus vaccine is efficient to protect allergic mice from further influenza infection, and it does not exacerbate but reduces IL-4 and IL-6 of allergic asthma. Conclusion Influenza vaccination is essential and efficient for allergic subjects to protect influenza virus infection. [ABSTRACT FROM AUTHOR]

An outbreak of respiratory adenovirus infection in children was observed in northern Taiwan between November 2004 and February 2005. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to determine the serotype(s) of 172 adenovirus isolates in the outbreak period, we found that adenovirus type 3 (Ad3) was the predominant type (87.2%), followed by Ad2 (6.4%), Ad1 (4.1%), Ad7 (1.2%), Ad4 (0.6%), and Ad5 (0.6%). The genotype of Ad3 was analyzed for 15 isolates from the outbreak period by RFLP of the full-length genome. All these isolates belonged to genotype Ad3a2. Compared with the Ad3-infected patients in the baseline period, a significantly higher proportion of Ad3-infected patients in the outbreak period had severe infections (58.0% vs. 40.2%, P = 0.01), which included bronchopneumonia (28.7%), exudative tonsillitis (24.1%), and tonsillitis (16.1%). Moreover, patients with severe infections were significantly younger than those without (4.10 vs. 8.15 years, P < 0.001). In summary, our study demonstrated that Ad3 was the predominant serotype responsible for the respiratory adenovirus outbreak in northern Taiwan during 2004-2005 and was associated with severe infections in the outbreak period. J. Med. Virol. 80:102-112, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Introduction The incidence of recent hepatitis C virus infection (HCV) infection has been noted to be increasing among men who have sex with men (MSM), especially those with HIV infection, in several resource-rich settings. In Taiwan, the incidence of recent HCV infection increased from 0 in 1994-2000, 2.29 in 2001-2005 to 10.13 per 1000 person-years of follow-up (PYFU) in 2006-2010. In this study, we aimed to estimate the incidence rate of recent HCV infection among those individuals who sought voluntary counselling and testing (VCT) service at a University Hospital. Methods Between May 2006 and December 2013, 18,246 tests for HIV antibody were performed among 12,143 individuals at the VCT services. A total of 2157 clients without HIV or HCV infection at baseline were included for estimation of incidence rate of recent HCV infection. Antibodies to HCV were determined with a third-generation enzyme immunoassay. A nested case-control study with four matched controls without HCV seroconversion for one HCV seroconverter was conducted to investigate the factors associated with recent HCV infection. Phylogenetic analysis was performed among the HCV strains obtained from VCT clients and patients coinfected with HIV and HCV between 2006 and 2013. Results During the study period, 2157 clients received a total of 8260 tests. The HCV seroprevalence at baseline was 0.3%. Of the 2150 HCV-negative clients who contributed 5074.99 PYFU, 17 developed HCV seroconversion (incidence rate, 3.35 per 1000 PYFU; 95% CI, 1.76-4.94); the rate increased from 2.28 per 1000 PYFU (95% CI, 0.05-4.51) in 2006-2009, to 3.33 per 1000 PYFU (95% CI, 0.86-5.80) in 2010-2011, to 4.94 per 1000 PYFU (95% CI, 0.99-8.99) in 2012-2013. In case-control study, HCV seroconverters were more likely to have HIV-infected partners, recent syphilis and a Rapid Plasma Reagin (RPR) titre of 4 or greater. In multivariate analysis, having HIV-infected partners remained as the only independent associated factors with HCV seroconversion (AOR, 6.931; 95% CI, 1.064-45.163). Phylogenetic analysis revealed transmission pairs and clusters, with most clustered sequences derived from MSM. Conclusions Similar to the observation among HIV-infected patients who are not IDUs, increasing trends of recent HCV infection also occur among the individuals who sought VCT services in Taiwan. Having HIV-infected partners is independently associated with recent HCV seroconversion. [ABSTRACT FROM AUTHOR]

Introduction Wide inter-patient variation of plasma efavirenz (EFV) concentrations has been observed, and a substantial proportion of HIV-positive patients may have unnecessarily higher plasma EFV concentrations than recommended while receiving EFV-containing combination antiretroviral therapy (cART) at the currently recommended daily dose of 600 mg. A lower daily dose (400 mg) of EFV has recently been demonstrated to be as efficacious as the recommended 600 mg when combined with tenofovir/mtricitabine in a multinational clinical trial, with a lower incidence of adverse effects. We aimed to use a therapeutic drug monitoring (TDM)-guided strategy to optimize the EFV dose in HIV-positive Taiwanese patients. Materials and Methods The plasma EFV concentrations at 12 hours (C12) after taking the previous dose were determined among HIV-positive adults who had received EFV-containing cART with viral suppression (plasma HIV RNA load (PVL) <200 copies/mL). For those with EFV C12 >2.0 mg/L, EFV (Stocrit, MSD) was reduced to half a tablet daily. Determinations of EFV C12 were repeated 4-12 weeks after switch using high-performance liquid chromatography. CYP2B6 G516T polymorphisms were determined using polymerase-chain-reaction restriction fragment-length polymorphism. Results Between April 2013 and June 2014, 111 patients (95.5% male; mean age, 39 years; 96.4% with PVL <40 copies/ml; 26.4% HBsAg-positive and 7.5% anti-HCV-positive) with plasma C12 efavirenz >2.0 mg/L were switched to a reduced dose (1/2# hs) of EFV; 45.5% of them had CYP2B6 G516T or TT genotypes; and 32.4% weighed 60 kg or less. The mean baseline EFV C12 before switch was 3.65 mg/L (interquartile range (IQR), 2.62-4.17) for 111 patients, which decreased to 1.96 mg/L (IQR, 1.53-2.33) for 64 patients who had completed follow-up of C12 EFV 4 weeks after switch, with a reduction of 49.4% (IQR, 38.9-57.0%). As of 10 July, 2014, all of the 38 patients (100%) who had completed at least one follow-up of PVL achieved undetectable PVL (<40 copies/ml) following switch to a reduced dose of EFV after a mean observation of 13 weeks (IQR, 7-15 weeks). Conclusions Switch to cART containing a half tablet of EFV (1/2#) in HIV-positive Taiwanese patients with higher plasma EFV concentrations who had achieved viral suppression could maintain successful viral suppression with the guidance of TDM. [ABSTRACT FROM AUTHOR]

Introduction The total case number of persons who are newly diagnosed with HIV continues to increase in Taiwan and men who have sex with men (MSM) have re-emerged as the leading risk group for HIV transmission. In this study, we aimed to estimate the incidence rate of HIV infection among those individuals who sought voluntary counselling and testing (VCT) service at a university hospital. Methods Between 1 April, 2006 and 31 December, 2013, 18,246 tests for HIV antibody were performed among 12143 individuals at the VCT service. A total of 2157 individuals who tested negative for anti-HIV antibody had subsequent follow-up tests at the same VCT service, which composed the study population for estimation of incidence rate of recent HIV infection. The BED assays were used to identify recent HIV infections that occurred within the previous six months before seeking VCT service. Results During the 6.5-year study period, 647 individuals were diagnosed as being HIV-positive, with an overall HIV seroprevalence of 3.55% (95% CI 3.27-3.82). The overall incidence rate of HIV infection was estimated 4.13 per 100 person-years of follow-up (95% CI 3.67-4.69 per 100 person-years of follow-up). MSM had an estimated 10-fold higher seroprevalence and seroincidence of HIV than heterosexuals. Of 647 clients testing positive for HIV, 603 clients were MSM (93.2%) and 477 patients (70.8%) subsequently sought HIV care at the hospital; 226 (47.4%) were diagnosed as having recent HIV infections by the BED assay, while 244 (51.2%) long-term infection and 7 without data by the BED assay. Of those patients, 173 (75.6%) and 178 patients (73.0%) with recent HIV infection and long-term infection had data of transmitted drug resistance mutations, respectively. The prevalence of transmitted drug resistance mutations to any class of antiretroviral therapy was 9.0% and 10.6% (p=0.68), respectively, of the HIV-1 strains from the patients with recent HIV infection and long-term infection, respectively. Conclusions The seroincidence rate of HIV among persons seeking VCT was estimated 4.13 per 100 person-years of follow-up. The prevalence of transmitted drug resistance to any class of antiretroviral agents was similar between those who were recently infected with HIV and those who had long-term infection in Taiwan. [ABSTRACT FROM AUTHOR]

The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants has altered the trajectory of the COVID-19 pandemic and raised some uncertainty on the long-term efficiency of vaccine strategy. The development of new therapeutics against a wide range of SARS-CoV-2 variants is imperative. We, here, have designed an inhalable siRNA, C6G25S, which covers 99.8% of current SARS-CoV-2 variants and is capable of inhibiting dominant strains, including Alpha, Delta, Gamma, and Epsilon, at picomolar ranges of IC 50 in vitro. Moreover, C6G25S could completely inhibit the production of infectious virions in lungs by prophylactic treatment, and decrease 96.2% of virions by cotreatment in K18-hACE2-transgenic mice, accompanied by a significant prevention of virus-associated extensive pulmonary alveolar damage, vascular thrombi, and immune cell infiltrations. Our data suggest that C6G25S provides an alternative and effective approach to combating the COVID-19 pandemic., (© 2022 The Authors. Published under the terms of the CC BY 4.0 license.)