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Cell encapsulation into spherical microparticles is a promising bioengineering tool in many fields, including 3D cancer modelling and pre-clinical drug discovery. Cancer microencapsulation models can more accurately reflect the complex solid tumour microenvironment than 2D cell culture and therefore would improve drug discovery efforts. However, these microcapsules, typically in the range of 1 - 5000 µm in diameter, must be carefully designed and amenable to high-throughput production. This review therefore aims to outline important considerations in the design of cancer cell microencapsulation models for drug discovery applications and examine current techniques to produce these. Extrusion (dripping) droplet generation and emulsion-based techniques are highlighted and their suitability to high-throughput drug screening in terms of tumour physiology and ease of scale up is evaluated.

Competing Interests: Competing interests: For activities unrelated to the work reported here, Tasha Ramsey has received speaker’s honoraria from the Canadian Society of Hospital Pharmacists (CSHP) and has served in a volunteer capacity on the CSHP Education Committee and the Nova Scotia Emerging and Re-emerging Infections Therapeutics and Prophylactics Recommendation Group; Mackenzie d’Entremont-Harris received travel support from the Nova Scotia Health Pharmacy Department Education Fund and the Queen Elizabeth II Division of Vascular Surgery and has served in a volunteer capacity on the Awards Committee of the Nova Scotia Branch, CSHP; Lisa Nodwell has served in a volunteer capacity as the Nova Scotia Branch Advocacy Representative to CSHP Council; and Lisa Barrett has received grants, consulting fees, and speaker’s honoraria from Abbvie and Gilead and has served in a volunteer capacity on the Nova Scotia Emerging and Re-emerging Infections Therapeutics and Prophylactics Recommendation Group. No other competing interests were declared.

Background: Allogeneic haematopoietic stem-cell transplantation (allo-HSCT) markedly reduces HIV reservoirs, but the mechanisms by which this occurs are only partly understood. In this study, we aimed to describe the dynamics of virological and immunological markers of HIV persistence after allo-HSCT., Methods: In this prospective observational cohort study, we analysed the viral reservoir and serological dynamics in IciStem cohort participants with HIV who had undergone allo-HSCT and were receiving antiretroviral therapy, ten of whom had received cells from donors with the CCR5Δ32 mutation. Participants from Belgium, Canada, Germany, Italy, the Netherlands, Spain, Switzerland, and the UK were included in the cohort both prospectively and retrospectively between June 1, 2014 and April 30, 2019. In the first 6 months after allo-HSCT, participants had monthly assessments, with annual assessments thereafter, with the protocol tailored to accommodate for the individual health status of each participant. HIV reservoirs were measured in blood and tissues and HIV-specific antibodies were measured in plasma. We used the Wilcoxon signed-rank test to compare data collected before and after allo-HSCT in participants for whom longitudinal data were available. When the paired test was not possible, we used the Mann-Whitney U test. We developed a mathematical model to study the factors influencing HIV reservoir reduction in people with HIV after allo-HSCT., Findings: We included 30 people with HIV with haematological malignancies who received a transplant between Sept 1, 2009 and April 30, 2019 and were enrolled within the IciStem cohort and included in this analysis. HIV reservoirs in peripheral blood were reduced immediately after full donor chimerism was achieved, generally accompanied by undetectable HIV-DNA in bone marrow, ileum, lymph nodes, and cerebrospinal fluid, regardless of donor CCR5 genotype. HIV-specific antibody levels and functionality values declined more slowly than direct HIV reservoir values, decaying significantly only months after full donor chimerism. Mathematical modelling suggests that allogeneic immunity mediated by donor cells is the main viral reservoir depletion mechanism after massive reservoir reduction during conditioning chemotherapy before allo-HSCT (half-life of latently infected replication-competent cells decreased from 44 months to 1·5 months)., Interpretation: Our work provides, for the first time, data on the effects of allo-HSCT in the context of HIV infection. Additionally, we raise the question of which marker can serve as the last reporter of the residual viraemia, postulating that the absence of T-cell immune responses might be a more reliable marker than antibody decline after allo-HSCT., Funding: amfAR (American Foundation for AIDS Research; ARCHE Program), National Institutes of Health, National Institute of Allergy and Infectious Diseases, and Dutch Aidsfonds., Competing Interests: Declaration of interests AB reports grants from Gilead Sciences and participating on the advisory board of ViiV Healthcare. AW reports funding for this manuscript from the American Foundation for AIDS Research (amfAR) and Aidsfunds; grants from Gilead and NOW; consulting fees from ViiV Healthcare/GSK, MSD, and Gilead Sciences; participating on the board of the Dutch Federation of Medical Microbiology, the board of the European Society for Translational Antiviral Research, chair on the IAS-USA mutations work group, the Committee of ZonMW (Dutch research organization) Research, and the Committee of the Dutch Federation for Long Covid; and received funding from Ark. AS-C reports funding for this manuscript from amfAR; grants from ANRS, the National Institutes of Health (NIH), Institute Pasteur, and MSDAVENIR; honoraria from MSD, ViiV Healthcare, and Gilead Sciences; and is chair of the Scientific and Medical Committee of Sidaction. B-EOJ reports consulting fees from Gilead Sciences, ViiV Healthcare, and Merck Sharp & Dohme; honoraria from Gilead Sciences and ViiV Healthcare; travel expenses for attending meetings from Gilead; and is scientific secretary for the German AIDS Society. BR reports honoraria from Gilead Sciences, Janssen, and ViiV Healthcare; payment for advice from ViiV Healthcare; and travel expenses for attending meetings and travel from ViiV Healthcare and Gilead Sciences. GH reports travel expenses for attending the meeting and travel for the HIV Persistence Workshop 2022. JB reports receiving honoraria from AbbVie, Pfizer, and Gilead Sciences; and travel expenses for attending meetings from AbbVie, Pfizer, and Gilead Sciences. JK reports grants from Novartis and Miltenyi Biotech; royalties from GADETA and Miltenyi Biotech; a patent with GADETA; and holds stock interest in GADETA. JM-P reports funding for this manuscript from amfAR. JSZW reports funding for this manuscript from The German Center for Infection Research, EU H2020 Research and Innovation Programme, HW & J Hector Foundation, the German Research Foundation, The Hamburg Investment and Development Bank, and amfAR; and honoraria from Nobite, GSK, and Gilead Sciences. JTS reports funding for this manuscript from the NIH and National Institute of Allergy and Infectious Diseases. LB report grants from Abbvie and Gilead Sciences; consulting fees from Abbvie and Gilead Sciences; and honoraria from AbbVie and Gilead Sciences. LV reports receiving grants from ViiV Healthcare and Gilead Sciences; and consulting fees from ViiV Healthcare and Gilead Sciences. MJG and GA declare being an employee of Ragon Institute of Mass General, MIT, and Harvard during the study; and an employee of Moderna afterwards. MNi reports receiving consulting fees from Gilead Sciences; and honoraria for lectures from ViiV Healthcare. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Antigen-based rapid diagnostic tests (Ag-RDTs) were widely deployed to enhance SARS-CoV-2 testing capacity during the COVID-19 pandemic. Consistent with national guidance for low prevalence settings, positive Ag-RDTs were confirmed using nucleic acid amplification tests (NAATs) to avoid false positive results. However, increasing demands for positive Ag-RDT confirmation competed with other testing priorities in clinical laboratories. This work hypothesized that real-time RT-PCR without nucleic acid extraction (NAE) would be sufficiently sensitive to support positive Ag-RDT confirmation. Ag-RDT and NAAT results from community-based asymptomatic testing sites prior to the omicron variant wave were compared to calculate the weekly false positive rate (FPR) and false detection rate (FDR). Real-time RT-PCR was compared with and without NAE using 752 specimens previously tested positive for SARS-CoV-2 using commercial NAATs and 344 specimens from Ag-RDT-positive individuals. The impact of SARS-CoV-2 prevalence on laboratory resources required to sustain Ag-RDT confirmation was modeled for the RT-PCR with and without NAE. Overall, FPR was low [0.07% (222/330,763)] in asymptomatic testing sites, but FDR was high [30.7% (222/724)]. When RT-PCR was compared with and without NAE, 100% concordance was obtained with NAAT-positive specimens, including those from Ag-RDT-positive individuals. NAE-free RT-PCR significantly reduced time to results, human resources, and overall costs. A 30.7% FDR reaffirms the need for NAAT-based confirmation of positive Ag-RDT results during low SARS-CoV-2 prevalence. NAE-free RT-PCR was shown to be a simple and cost-sparing NAAT-based solution for positive Ag-RDT confirmation, and its implementation supported data-driven broader Ag-RDT deployment into communities, workplaces, and households., Importance: Rapid antigen testing for SARS-CoV-2 was widely deployed during the COVID-19 pandemic. In settings of low prevalence, national guidance recommends that positive antigen test results be confirmed with molecular testing. Given the high testing burden on clinical laboratories during the COVID-19 pandemic, the high volume of positive antigen tests submitted for confirmatory testing posed challenges for laboratory workflow. This study demonstrated that a simple PCR method without prior nucleic acid purification is an accurate and cost-effective solution for positive rapid antigen test confirmation. Implementing this method allowed molecular confirmatory testing for positive antigen tests to be sustained as antigen testing was expanded into large populations such as workplaces, schools, and households., Competing Interests: The authors declare no conflict of interest.

The COVID-19 pandemic has been hallmarked by several waves of variants of concern (VoCs), each with novel challenges. Currently, the highly transmissible Omicron VoC is predominant worldwide, and sore throat is common, among other cold-like symptoms. Anecdotes on social media have suggested that sampling one's throat can increase the sensitivity for Omicron detection by antigen-based rapid testing devices (Ag-RDTs). This work aimed to improve the local testing strategy and determine whether the sensitivity of Ag-RDTs designed for nasal sampling is altered with the use of self-administered throat swabs in self-perceived asymptomatic individuals. This investigation used a common Ag-RDT (i.e., Abbott Panbio COVID-19 Ag rapid test device) to compare three sampling sites: nasal swab, throat swab, and combined nasal/throat. All Ag-RDT results were confirmed with molecular testing from residual test buffer. Compared to reverse transcriptase PCR (RT-PCR), samples from nasal or throat swabs each detected 64.5% of SARS-CoV-2 cases; however, combining the contributions of each swab increased the positive percent agreement (PPA) with RT-PCR to 88.7%. This trend was also evident with the Rapid Response Ag-RDT (BTNX), which uses more flexible swabs than does the Panbio. When nasal swab collection was compared to paired sampling of the nose/throat using a single swab with the Panbio Ag-RDT, the PPAs were 68.4% and 81.6%, respectively. No false-positive results were observed with nasal, throat, or combined nasal/throat sampling. Self-administered throat and nasal/throat swabs both had >90% acceptability. These findings support the use of self-collected combined nasal/throat sampling for Ag-RDT-based SARS-CoV-2 detection in self-perceived asymptomatic individuals. IMPORTANCE This quality project demonstrates that combining the results of nasal and throat swabs or using a combined single swab of the throat and nares resulted in increased detection of SARS-CoV-2 using a rapid antigen test, in an asymptomatic population. Importantly, no false positives were detected, and over 90% of people were willing to perform the combination swab. These types of projects are instrumental in informing local practices to improve testing strategies. These data support the option of using a combined nasal/throat swab in our local setting to enhance the detection of Omicron.

Antigen-based rapid diagnostic tests (Ag-RDTs) have been widely used for the detection of SARS-CoV-2 during the coronavirus disease 2019 (COVID-19) pandemic. In settings of low disease prevalence, such as asymptomatic community testing, national guidelines recommend confirmation of positive Ag-RDT results with a nucleic acid amplification test (NAAT). This often requires patients to be recalled for repeat specimen recollection and subsequent testing in reference laboratories. This project assessed the use of a point-of-care molecular NAAT for SARS-CoV-2 detection (i.e., ID NOW), which was performed on-site at a volunteer-led asymptomatic community testing site on the residual test buffer (RTB) from positive Ag-RDTs. The ID NOW NAAT assay was performed on RTB from two Ag-RDTs: the Abbott Panbio and BTNX Rapid Response assays. Results of ID NOW were compared to real-time RT-PCR at a reference laboratory. Along with investigations into the clinical performance of ID NOW on RTB, analytical specificity was assessed with a panel of various respiratory organisms. Of the Ag-RDTs results evaluated, all 354 Ag-RDTs results characterized as true positives by RT-PCR were accurately identified with ID NOW testing of RTB. No SARS-CoV-2 detections by ID NOW were observed from 10 specimens characterized as false-positive Ag-RDTs, or from contrived specimens with various respiratory organisms. The use of on-site molecular testing on RTB provides a suitable option for rapid confirmatory testing of positive Ag-RDTs, thereby obviating the need for specimen recollection for molecular testing at local reference laboratories. IMPORTANCE During the COVID-19 pandemic, rapid antigen tests have been widely used for the detection of SARS-CoV-2. These simple devices allow rapid test results. However, false-positive results may occur. As such, individuals with positive rapid tests often must return to testing centers to have a second swab collected, which is then transported to a specialized laboratory for confirmation using molecular tests. As an alternative to requiring a repeat visit and a prolonged turn-around time for result confirmation, this project evaluated whether the leftover material from rapid antigen tests could be confirmed directly on a portable point-of-care molecular instrument. Using this approach, molecular confirmation of positive antigen tests could be performed in less than 15 min, and the results were equivalent to laboratory-based confirmation. This procedure eliminates the need for individuals to return to testing centers following a positive rapid antigen test and ensures accurate antigen test results through on-site confirmation.

Background: Hepatitis B virus (HBV) nucleos(t)ide analog (NA) therapy reduces liver disease but requires prolonged therapy to achieve hepatitis B surface antigen (HBsAg) loss. There is limited North American real-world data using non-invasive tools for fibrosis assessment and few have compared 1 st generation NA or lamivudine (LAM) to tenofovir disoproxil fumarate (TDF)., Aim: To assess impact of NA on virological response and fibrosis regression using liver stiffness measurement (LSM) ( i.e. , FibroScan ® )., Methods: Retrospective, observational cohort study from the Canadian HBV Network. Data collected included demographics, NA, HBV DNA, alanine aminotransferase (ALT), and LSM. Patients were HBV monoinfected patients, treatment naïve, and received 1 NA with minimum 1 year follow-up., Results: In 465 (median 49 years, 37% female, 35% hepatitis B e antigen + at baseline, 84% Asian, 6% White, and 9% Black). Percentage of 64 ( n = 299) received TDF and 166 were LAM-treated with similar median duration of 3.9 and 3.7 years, respectively. The mean baseline LSM was 11.2 kPa (TDF) vs 8.3 kPa (LAM) ( P = 0.003). At 5-year follow-up, the mean LSM was 7.0 kPa in TDF vs 6.7 kPa in LAM ( P = 0.83). There was a significant difference in fibrosis regression between groups ( i.e. , mean -4.2 kPa change in TDF and -1.6 kPa in LAM, P < 0.05). The last available data on treatment showed that all had normal ALT, but more TDF patients were virologically suppressed (< 10 IU/mL) ( n = 170/190, 89%) vs LAM-treated ( n = 35/58, 60%) ( P < 0.05). None cleared HBsAg., Conclusion: In this real-world North American study, approximately 5 years of NA achieves liver fibrosis regression rarely leads to HBsAg loss., Competing Interests: Conflict-of-interest statement: Dr. Alnoor Ramji and Dr. Carla S Coffin didn’t receive at any time payment from a third party for any aspect for the submitted work; there are no relevant conflict of interest; there are no patents related to this work; Dr. Alnoor Ramji and Dr. Carla S Coffin have nothing to disclosure., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Containment measures employed during the COVID-19 pandemic included prompt recognition of cases, isolation, and contact tracing. Bilateral nasal (NA) swabs applied to a commercial antigen-based rapid diagnostic test (Ag-RDT) offer a simpler and more comfortable alternative to nasopharyngeal (NP) collection; however, little is known about the sensitivity of this method in an asymptomatic population. Participants in community-based asymptomatic testing sites were screened for SARS-CoV-2 using an Ag-RDT with NP sampling. Positive individuals returned for confirmatory molecular testing and consented to repeating the Ag-RDT using a bilateral NA swab for comparison. Residual test buffer (RTB) from Ag-RDTs was subjected to real-time reverse transcription-PCR (RT-PCR). Of 123,617 asymptomatic individuals, 197 NP Ag-RDT-positive participants were included, with 175 confirmed positive by RT-PCR. Of these cases, 154 were identified from the NA swab collection with Ag-RDT, with a sensitivity of 88.0% compared to the NP swab collection. Stratifying results by RT-PCR cycle threshold demonstrated that sensitivity of the nasal collection method varied based on the cycle threshold ( C T ) value of the paired RT-PCR sample. RT-PCR testing on the RTB from the Ag-RDT using NP and NA swab collections resulted in 100.0% and 98.7% sensitivity, respectively. NA swabs provide an adequate alternative to NP swab collection for use with Ag-RDT, with the recognition that the test is most sensitive in specimens with high viral loads. With the high sensitivity of RT-PCR testing on RTB from Ag-RDT, a more streamlined approach to confirmatory testing is possible without recollection or use of paired collections strategies. IMPORTANCE Nasal swabbing for SARS-CoV-2 (COVID-19) comes with many benefits but is slightly less sensitive than traditional nasopharyngeal swabbing; however, confirmatory lab-based testing could be performed directly from the residual buffer from either sample type.

Background: Addiction treatment and harm reduction services reduce risks of death and re-infection among patients with injection drug use-associated infective endocarditis (IDU-IE), but these are not offered at many hospitals. Among hospitalized patients with IDU-IE at the two tertiary-care hospitals in the Canadian Maritimes, we aimed to identify (1) the availability of opioid agonist treatment (OAT) and sterile drug injecting equipment, and (2) indicators of potential unmet addiction care needs., Methods: Retrospective review of IDU-IE hospitalizations at Queen Elizabeth II Health Sciences Centre (Halifax, Nova Scotia) and the Saint John Regional Hospital (Saint John, New Brunswick), October 2015 -March 2017. In Halifax, there are no addiction medicine providers on staff; in Saint John, infectious diseases physicians also practice addiction medicine. Inclusion criteria were: (1) probable or definite IE as defined by the modified Duke criteria; and (2) injection drug use within the prior 3 months., Results: We identified 38 hospitalizations (21 in Halifax and 17 in Saint John), for 30 unique patients. Among patients with IDU-IE and untreated opioid use disorder, OAT was offered to 36% (5/14) of patients in Halifax and 100% (6/6) of patients in Saint John. Once it was offered, most patients at both sites initiated OAT and planned to continue it after discharge. In Halifax, no patients were offered sterile injecting equipment, and during five hospitalizations staff confiscated patients' own equipment. In Saint John, four patients were offered (and one was provided) injecting equipment in hospital, and during two hospitalizations staff confiscated patients' own equipment. Concerns regarding undertreated pain or opioid withdrawal were documented during 66% (25/38) of hospitalizations, and in-hospital illicit or non-medical drug use during 32% (12/38). Two patients at each site (11%; 4/38) had self-directed discharges against medical advice., Conclusions: Patients with IDU-IE in the Canadian Maritimes have unequal access to evidence-based addiction care depending on where they are hospitalized, which differs from the community-based standard of care. Indicators of potential unmet addiction care needs in hospital were common., Competing Interests: The authors have declared that no competing interests exist.

The prevalence of inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis, in Canada, is over 0.75% in 2021. Many individuals with IBD are immunocompromised. Consequently, the World Health Organization's declaration of a global pandemic uniquely impacted those with IBD. Crohn's and Colitis Canada (CCC) formed the COVID-19 and IBD Taskforce to provide evidence-based guidance during the pandemic to individuals with IBD and their families. The Taskforce met regularly through the course of the pandemic, synthesizing available information on the impact of COVID-19 on IBD. At first, the information was extrapolated from expert consensus guidelines, but eventually, recommendations were adapted for an international registry of worldwide cases of COVID-19 in people with IBD. The task force launched a knowledge translation initiative consisting of a webinar series and online resources to communicate information directly to the IBD community. Taskforce recommendations were posted to CCC's website and included guidance such as risk stratification, management of immunosuppressant medications, physical distancing, and mental health. A weekly webinar series communicated critical information directly to the IBD community. During the pandemic, traffic to CCC's website increased with 484,755 unique views of the COVID-19 webpages and 126,187 views of the 23 webinars, including their video clips. CCC's COVID-19 and IBD Taskforce provided critical guidance to the IBD community as the pandemic emerged, the nation underwent a lockdown, the economy reopened, and the second wave ensued. By integrating public health guidance through the unique prism of a vulnerable population, CCC's knowledge translation platform informed and protected the IBD community., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Canadian Association of Gastroenterology.)

Persons with inflammatory bowel disease (IBD) make up more than 0.75% of the Canadian population in 2021. Early in the COVID-19 pandemic, individuals with IBD, particularly those on immunosuppressive therapies, were concerned that their health status may place them at higher risk of contracting COVID-19 or experiencing more severe disease course if infected with SARS-CoV-2. In response, Crohn's and Colitis Canada developed the COVID-19 and IBD Taskforce in March 2020 to rapidly synthesize the evolving knowledge of COVID-19 as relevant to Canadians with IBD. The Taskforce communicated expert information directly to the Canadian IBD community through online tools and a webinar series. In order to understand the full impact of COVID-19 on the IBD community, Crohn's and Colitis Canada commissioned a policy report that was informed through a systematic literature review and synthesized across working groups along the following domains: Epidemiology, Children and Expectant Mothers with IBD, Seniors with IBD, Mental Health, Risk Factors and Medications, Vaccines, and Healthcare Delivery during the Pandemic and the Future Model of IBD Care. This report from Canadian physicians, researchers, and IBD community representatives highlights the physical, mental, and health systems impact of COVID-19 on the entire spectrum of the IBD community, including children, adolescents, adults, seniors, and pregnant people with IBD. This executive summary provides an overview of the crucial information from each of the chapters of the policy report, supplemented with additional information made available through Crohn's and Colitis Canada's webinar-based knowledge translation platform., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Canadian Association of Gastroenterology.)

Colonic ischemia most often presents with abdominal pain and rectal bleeding. Presentation of colonic ischemia as a prominent mass is exceptionally unique and is not often reported. Concern for neoplasm prompted a repeat scope, which revealed the mass had vanished. We present a case of colonic ischemia, which produced a transient colonic mass formed by inflammatory tissue and clots., (© 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)

Background: Alcohol use and hepatitis C virus (HCV) are two leading causes of liver disease. Alcohol use is prevalent among the HCV-infected population and accelerates the progression of HCV-related liver disease. Despite barriers to care faced by HCV-infected patients who use alcohol, few studies have analyzed uptake of direct-acting antiviral (DAA) treatment., Objective: We compared rates of treatment uptake and sustained virological response (SVR) between patients with and without alcohol use., Methods: Prospective data were obtained from the Canadian Network Undertaking against Hepatitis C (CANUHC) cohort. Consenting patients assessed for DAA treatment between January 2016 and December 2019 were included. Demographic and clinical characteristics were compared between patients with and without alcohol use by means of t -tests, χ 2 tests, and Fisher's Exact Tests. Univariate and multivariate analyses were used to determine predictors of SVR and treatment initiation., Results: Current alcohol use was reported for 217 of 725 (30%) patients. The proportion of patients initiating DAA treatment did not vary by alcohol use status (82% versus 83%; p  = 0.99). SVR rate was similar between patients with alcohol use and patients without alcohol use (92% versus 94%; p  = 0.45). Univariate and multivariate analysis found no association between alcohol use and SVR or treatment initiation., Conclusion: Patients engaged in HCV treatment have highly favourable treatment uptake and outcomes regardless of alcohol use. Public health interventions should be directed toward facilitating access to care for all patients irrespective of alcohol use. Research into high-level alcohol use and DAA outcomes is needed., Competing Interests: CC is an advisor and speaker with Merck, Gilead, and AbbVie., (Copyright © 2021 Canadian Association for the Study of the Liver.)

Competing Interests: MKA reports grants from the Canadian Frailty Network, Canadian Institutes of Health Research, Public Health Agency of Canada, Sanofi, Pfizer, and GlaxoSmithKline, and personal fees from Pfizer, Sanofi, and Seqirus, outside the submitted work. LB reports grants from CIHR, the Canadian COVID Immunity Task Force, Gilead, ViiV, Abbvie, Merck, and honoraria for advisory activities from Gilead, ViiV, Abbvie, and Merck outside the submitted work.

Histamine receptor 2 (H2R) blockade is commonly used in patients with gastric, duodenal ulcers or gastroesophageal reflux disease. Beyond the gastrointestinal tract, H2R is expressed by multiple immune cells, yet little is known about the immunomodulatory effects of such treatment. Clinical reports have associated H2R blockade with leukopenia, neutropenia, and myelosuppression, and has been shown to provide clinical benefit in certain cancer settings. To systematically assess effects of H2R blockade on key immune parameters, a single-center, single-arm clinical study was conducted in 29 healthy subjects. Subjects received daily high dose ranitidine for 6 weeks. Peripheral blood immunophenotyping and mediator analysis were performed at baseline, 3 and 6 weeks into treatment, and 12 weeks after treatment cessation. Ranitidine was well-tolerated, and no drug related adverse events were observed. Ranitidine had no effect on number of neutrophils, basophils or eosinophils. However, ranitidine decreased numbers of B cells and IL-2Rα (CD25) expressing T cells that remained lower even after treatment cessation. Reduced serum levels of IL-2 were also observed and remained low after treatment. These observations highlight a previously unrecognised immunomodulatory sustained impact of H2R blockade. Therefore, the immune impacts of H2R blockade may require greater consideration in the context of vaccination and immunotherapy.

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care., (© 2020 John Wiley & Sons Ltd.)

Background: There are multiple obstacles encountered by immigrants attempting to engage hepatitis C virus (HCV) care and treatment. We evaluated the diversity and treatment outcomes of HCV-infected immigrants evaluated for Direct Acting Antiviral (DAA) therapy in Canada., Methods: The Canadian Network Undertaking against Hepatitis C (CANUHC) Cohort contains demographic information and DAA treatment information prospectively collected at 10 Canadian sites. Information on country of origin and race are collected. Characteristics and outcomes (sustained virological response; SVR) were compared by immigration status and race., Results: Between January 2016 and May 2018, 725 HCV-infected patients assessed for DAA therapy were enrolled in CANUHC (mean age: 52.66 ± 12.68 years); 65.66% male; 82.08% White, 5.28% Indigenous, 4.64% South East Asian, 4.64% East Indian, 3.36% Black). 18.48% were born outside of Canada. Mean age was similar [immigrants: 54.36 ± 13.95 years), Canadian-born: 52.27 ± 12.35 years); (p = 0.085)]. The overall baseline fibrosis score (in kPa measured by transient elastography) was similar among Canadian and foreign-born patients. Fibrosis score was not predicted by race or genotype. The proportion initiating DAA therapy was similar by immigrant status (56.72% vs 49.92%). SVR rates by intent-to-treat analysis were similar (immigrants-89.47%, Canadian-born-92.52%; p = 0.575)., Conclusion: A diverse immigrant population is engaging care in Canada, initiating HCV antiviral therapy in an equitable fashion and achieving SVR proportions similar to Canada-born patients. Our Canadian experience may be of value in informing HCV elimination efforts in economically developed regions.

Background: Pancreatic ductal adenocarcinoma (PDAC) has poor survival and treatment options. PDAC cells shift their metabolism towards glycolysis, which fuels the plasma membrane calcium pump (PMCA), thereby preventing Ca 2+ -dependent cell death. The ATP-generating pyruvate kinase-M2 (PKM2) is oncogenic and overexpressed in PDAC. This study investigated the PKM2-derived ATP supply to the PMCA as a potential therapeutic locus., Methods: PDAC cell growth, migration and death were assessed by using sulforhodamine-B/tetrazolium-based assays, gap closure assay and poly-ADP ribose polymerase (PARP1) cleavage, respectively. Cellular ATP and metabolism were assessed using luciferase/fluorescent-based assays and the Seahorse XFe96 analyzer, respectively. Cell surface biotinylation identified membrane-associated proteins. Fura-2 imaging was used to assess cytosolic Ca 2+ overload and in situ Ca 2+ clearance. PKM2 knockdown was achieved using siRNA., Results: The PKM2 inhibitor (shikonin) reduced PDAC cell proliferation, cell migration and induced cell death. This was due to inhibition of glycolysis, ATP depletion, inhibition of PMCA and cytotoxic Ca 2+ overload. PKM2 associates with plasma membrane proteins providing a privileged ATP supply to the PMCA. PKM2 knockdown reduced PMCA activity and reduced the sensitivity of shikonin-induced cell death., Conclusions: Cutting off the PKM2-derived ATP supply to the PMCA represents a novel therapeutic strategy for the treatment of PDAC.

Background: Published Canadian epidemiologic data on hepatitis B virus (HBV) infection include single-centre studies or are focused on Indigenous populations. We performed a study to characterize the demographic and clinical features, liver disease status and treatment of people with chronic hepatitis B in Canada., Methods: In this descriptive, opportunistic, cross-sectional study, available data for people known to be monoinfected with HBV were collected by the Canadian HBV Network from existing clinical databases, with support from the National Microbiology Laboratory, Public Health Agency of Canada. Data were collected in all provinces with the exception of New Brunswick and Newfoundland and Labrador. We analyzed the data using parametric and nonparametric statistical methods, with a significance level of p < 0.05., Results: In the 9380 unique patient records reviewed, the median age was 48 years, and 5193 patients (55.4%) were male. Ethnicity information was available for 7858 patients, of whom 5803 (73.8%) were Asian, 916 (11.6%) were black and 914 (11.6%) were white. Most of those tested (5556/6796 [81.8%]) were negative for HBV e-antigen, and most of those with fibrosis data (3481/4260 [81.7%]) had minimal liver fibrosis, with more advanced fibrosis noted in older people (> 40 yr). Of the 980 patients with genotype data, 521 (53.2%) had genotype B or C infection. Most of the 9241 patients with known confirmed treatment status received tenofovir disoproxil fumarate (1655 [17.9%]), lamivudine (1434 [15.5%]) or entecavir (548 [5.9%])., Interpretation: Based on available data, Canadian patients with chronic hepatitis B are predominantly Asian and negative for HBV e-antigen, and have genotype B or C infection. Interprovincial variations were noted in antiviral treatment regimen. This multicentre nationwide study provides data regarding patients with chronic hepatitis B and may inform future studies on the epidemiologic features of HBV infection in Canada., Competing Interests: Competing interests: Carla Coffin reports investigator-initiated research grants/research materials from GlaxoSmithKline, Gilead Sciences, Arbutus Biopharma and Bristol-Myers Squibb, and educational grants from Merck, Gilead Sciences and Janssen Pharmaceutica. She is on the advisory board for Merck, Gilead Sciences and GlaxoSmithKline, and the Trial Guidance and Publication Committee for Spring Bank Pharmaceuticals, and has participated as a local site principal investigator in clinical trials for Gilead Sciences, Spring Bank Pharmaceuticals, Transgene and Janssen Pharmaceutica. Alnoor Ramji reports clinical investigator grants from Allergan, Arbutus Biopharma, Gilead Sciences, Janssen Pharmaceutica, Intercept Pharmaceuticals, Norvartis, Merck, Spring Bank Pharmaceuticals and Assembly Biosciences; personal fees from AbbVie, Gilead Sciences, Intercept Pharmaceuticals, Lupin and Merck; and grants from AbbVie, Celgene Corporation, Gilead Sciences, Janssen Pharmaceutica, Intercept Pharmaceuticals and Merck. Karen Doucette reports a grant from Gilead Sciences. Keith Tsoi reports personal fees from Gilead Sciences, Merck, AbbVie and Intercept Pharmaceuticals, and nonfinancial support from Gilead Sciences. Brian Conway reports grants and honoraria from AbbVie, Gilead Sciences, Indivior, Merck and Viiv Healthcare. He has acted as a consultant for these companies. Lisa Barrett reports grants from AbbVie and personal fees from AbbVie, Bristol-Myers Squibb, Gilead Sciences and ViiV Healthcare. Stephen Congly reports grants from Allergan, Gilead Sciences, Genfit, Boehringer Ingelheim and Bristol-Myers Squibb, and personal fees from Allergan. Edward Tam reports grants from AbbVie, Gilead Sciences, Merck, Intercept Pharmaceuticals and Janssen Pharmaceutica, and personal fees from AbbVie, Bristol-Myers Squibb, Gilead Sciences, Merck, Intercept Pharmaceuticals and Janssen Pharmaceutica. David Wong reports other funding from AbbVie, Merck and Gilead Sciences. Alex Wong reports grants and personal fees from Gilead Sciences. Harry Janssen reports grants from AbbVie, Bristol-Myers Squibb, Gilead Sciences, Janssen Pharmaceutica, MedImmune, Merck and Roche, and personal fees from AbbVie, Benitec Biopharma, Bristol-Myers Squibb, Gilead Sciences, Janssen Pharmaceutica, MedImmune, Roche, Arbutus Biopharma and Vir Biotechnology. Scott Fung reports speaking and teaching fees from Gilead Sciences and Bristol-Myers Squibb, and consulting fees from Gilead Sciences. No other competing interests were reported., (Copyright 2019, Joule Inc. or its licensors.)

Introduction: The availability of curative hepatitis C therapies has created an opportunity to improve treatment delivery and access. Local providers, government, industry, and community groups in Prince Edward Island developed an innovative province-wide care model. Our goal was to describe the first year of program implementation., Material and Methods: Using a communitybased prospective observational study design, all chronic hepatitis C referrals received from April 2015 to April 2016 were recorded in a database. Primary analysis assessed the time from referral to assessment/treatment, as well as the number of referrals, assessments, and treatment initiations. Secondary objectives included: (1) treatment effectiveness using intention-to-treat analysis; and (2) patient treatment experience assessed using demographics, adverse events, and medication adherence., Results: During the study period 242 referrals were received, 123 patients were seen for intake assessments, and 93 initiated direct-acting antiviral therapy based on medical need. This is compared to 4 treatment initiations in the previous 2 years. The median time from assessment to treatment initiation was 3 weeks. Eighty-two of 84 (97.6%, 95% CI 91.7 - 99.7%) patients for whom outcome data were available achieved sustained virologic response at 12 weeks post-treatment; 1 was lost to follow-up and 1 died from an unrelated event. In the voluntary registry, 39.7% of patients reported missed treatment doses., Conclusion: In conclusion, results from the first 12 months of this multi-phase hepatitis C elimination strategy demonstrate improved access to treatment, and high rates of safe engagement and cure for patients living with chronic hepatitis C genotype 1 infections., (Copyright © 2018 Fundación Clínica Médica Sur, A.C. Published by Elsevier España, S.L.U. All rights reserved.)

Competing Interests: Competing interests: Darrell Tan reports grants from the Canadian Institutes of Health Research and Ontario HIV Treatment Network, during the conduct of the study, and personal fees from Merck and GSK and grants and personal fees from Gilead and ViiV Healthcare, outside the submitted work. Mark Hull reports receiving honoraria for advisory board representation and speaking engagements regarding HIV and the hepatitis C virus from BMS, Gilead, Merck and ViiV Healthcare, paid to his institution. Deborah Yoong reports personal fees from Merck and Gilead Science, outside the submitted work. Cécile Tremblay reports grants and personal fees from Gilead, Merck, ViiV Healthcare, the Canadian Institutes of Health Research and Fonds de recherche santé Québec, both during the conduct of the study and outside the submitted work. Réjean Thomas reports personal fees from Gilead, outside the submitted work. Jean-Guy Baril reports grants from Gilead, Merck and Glaxo, and personal fees from Gilead, Merck and ViiV Healthcare, outside the submitted work. Joseph Cox reports grants and personal fees from ViiV Healthcare, and grants from Merck and Gilead, outside the submitted work. Pierre Giguere reports grants and personal fees from Gilead Sciences, ViiV Healthcare and Merck outside the submitted work. Marianne Harris reports grants and personal fees from Gilead Sciences Canada and personal fees from Merck Canada and ViiV Healthcare, outside the submitted work. Christine Hughes reports grants and personal fees from ViiV Healthcare, and personal fees from Merck Canada and Gilead Sciences Canada, outside the submitted work. Stephen Shafran reports grants from AbbVie, Gilead and Janssen; grants and personal fees from Merck and BMS; and personal fees from Pfizer, outside the submitted work. No other competing interests were declared.

Introduction: The availability of curative hepatitis C therapies has created an opportunity to improve delivery and access. Local providers, government, industry, and community groups in Prince Edward Island developed an innovative province-wide care model. Our goal was to describe the first year of program implementation., Material and Methods: Using a community based prospective observational study design, all chronic hepatitis C referrals received from April 2015 to April 2016 were recorded in a database. Primary analysis assessed the time from referral to assessment/treatment, as well as the number of referrals, assessments, and treatment initiations. Secondary objectives included: 1) Treatment effectiveness using intention-to-treat analysis; and 2) Patient treatment experience assessed using demographics, adverse events, and medication adherence., Results: During the study period 242 referrals were received, 123 patients were seen for intake assessments, and 93 initiated direct-acting antiviral therapy based on medical need. This is compared to 4 treatment initiations in the previous 2 years. The median time from assessment to treatment initiation was 3 weeks. Eighty-two of 84 (97.6%, 95% CI 91.7 - 99.7%) patients for whom outcome data were available achieved sustained virologic response at 12 weeks post-treatment; 1 was lost to follow-up and 1 died from an unrelated event. In the voluntary registry, 39.7% of patients reported missed treatment doses., Conclusion: In conclusion, results from the first 12 months of this multi-phase hepatitis C elimination strategy demonstrate improved access to treatment, and high rates of safe engagement and cure for patients living with chronic hepatitis C genotype 1 infections.

Background: In Canada, interferon-free, direct-acting antiviral hepatitis C virus (HCV) regimens are costly. This presents challenges for universal drug coverage of the estimated 220 000 people with chronic HCV infection nationwide. The study objective was to appraise criteria for reimbursement of 4 HCV direct-acting antivirals in Canada., Methods: We reviewed the reimbursement criteria for simeprevir, sofosbuvir, ledipasvir - sofosbuvir and paritaprevir - ritonavir - ombitasvir plus dasabuvir in the 10 provinces and 3 territories. Data were extracted from April 2015 to June 2016. The primary outcomes extracted from health ministerial websites were: 1) minimum fibrosis stage required, 2) drug and alcohol use restrictions, 3) HIV coinfection restrictions and 4) prescriber type restrictions., Results: Overall, 85%-92% of provinces/territories limited access to patients with moderate fibrosis (Meta-Analysis of Histologic Data in Viral Hepatitis stage F2 or greater, or equivalent). There were no drug and alcohol use restrictions; however, several criteria (e.g., active injection drug use) were left to the discretion of the physician. Quebec did not reimburse simeprevir and sofosbuvir for people coinfected with HIV; no restrictions were found in the remaining jurisdictions. Prescriber type was restricted to specialists in up to 42% of provinces/territories., Interpretation: This review of criteria of reimbursement of HCV direct-acting antivirals in Canada showed substantial interjurisdictional heterogeneity. The findings could inform health policy and support the development and adoption of a national HCV strategy., Competing Interests: See the end of the article.

Background. Hepatitis C virus (HCV) coinfection occurs in 20-30% of Canadians living with HIV and is responsible for a heavy burden of morbidity and mortality. Purpose. To update national standards for management of HCV-HIV coinfected adults in the Canadian context with evolving evidence for and accessibility of effective and tolerable DAA therapies. The document addresses patient workup and treatment preparation, antiviral recommendations overall and in specific populations, and drug-drug interactions. Methods. A standing working group with HIV-HCV expertise was convened by The Canadian Institute of Health Research HIV Trials Network to review recently published HCV antiviral data and update Canadian HIV-HCV Coinfection Guidelines. Results. The gap in sustained virologic response between HCV monoinfection and HIV-HCV coinfection has been eliminated with newer HCV antiviral regimens. All coinfected individuals should be assessed for interferon-free, Direct Acting Antiviral HCV therapy. Regimens vary in content, duration, and success based largely on genotype. Reimbursement restrictions forcing the use of pegylated interferon is not acceptable if optimal patient care is to be provided. Discussion. Recommendations may not supersede individual clinical judgement. Treatment advances published since December 2015 are not considered in this document.

Hepatitis C (HCV) treatment for patients coinfected with human immunodeficiency virus (HIV) and HCV is associated with modest rates of sustained virologic response (SVR) and an increased rate of relapse when compared to HCV monoinfected patients. As patients who attain SVR and patients who relapse are clinically indistinguishable during treatment, where both groups have fully suppressed HCV viral load, it has not been possible to identify in advance those who will relapse. Biomarkers that may distinguish patients with differential treatment response may be clinically useful and provide insight into mechanisms of relapse. In this retrospective study, serum and PBMCs were obtained from 41 HIV/HCV co-infected patients and 17 healthy volunteers. Changes in antibody titers to various regions of the HCV proteome during treatment for HCV were determined using a novel luciferase immunoprecipitation assay. Changes in B-cell subtypes in patients with differential treatment response as well as healthy volunteers were compared. This study demonstrates that elevated anti-HCV core antibody titers persisted during HCV treatment in patients who relapsed when compared to those who attained SVR. Furthermore, characterization of B cells in patients who relapsed demonstrated an abnormal B-cell phenotype distribution characterized by elevated frequencies of exhausted B cells among relapsers at baseline, which persisted despite suppression of HCV viremia at 24 weeks, along with increased frequencies of plasmablasts. These data suggest that anti-HCV specific B cells may be responding to ongoing subclinical HCV replication in patients who will relapse., (© 2015 Wiley Periodicals, Inc.)

Certain human class I histocompatibility-linked leukocyte antigen (HLA)/killer cell immunoglobulin-like receptor (KIR) genotypic combinations confer more favourable prognoses upon exposure to human immunodeficiency virus (HIV). These combinations influence natural killer (NK) cell function, thereby implicating NK cells in protection from HIV infection or disease progression. Because CD8(+) T cells restrict HIV replication, depend upon HLA class I antigen presentation and can also express KIR molecules, we investigated how these HLA/KIR combinations relate to the phenotype and function of CD8(+) T cells from uninfected controls and individuals with chronic HIV infection. CD8(+) T cells from KIR3DL1 and KIR3DS1 homozygous individuals, and expressing the corresponding KIR, were enumerated and phenotyped for CD127, CD57 and CD45RA expression. Ex vivo and in vitro responsiveness to antigen-specific and polyclonal stimulation was compared between KIR-expressing and non-expressing CD8(+) T cells by interferon-γ production. There were higher numbers and fractions of KIR3DL1-expressing CD8(+) T cells in HIV-infected individuals independent of HLA-Bw4 co-expression, whereas expansion of KIR3DS1-expressing CD8(+) T cells reflected HLA-Bw4*80I co-expression. KIR3DL1(+) and S1(+) CD8(+) T cells were predominantly CD127(-)CD57(+)CD45RA(+). KIR3DL1-expressing CD8(+) T cells were insensitive to ex vivo stimulation with peptides from HIV or common viruses, but responded to anti-CD3 and recovered responsiveness to common viruses in vitro. Ex vivo non-responsiveness of KIR3DL1-expressing CD8(+) T cells was also independent of HLA-Bw4. KIR3DS1-expressing T cells responded normally to ex vivo antigenic stimulation, illustrating functional superiority over KIR3DL1(+) CD8(+) T cells.

Chronic hepatitis C virus (HCV) infection increases all-cause mortality, rates of cirrhosis, hepatocellular carcinoma, liver transplantation and overall health care utilization. Morbidity and mortality disproportionately affect individuals born between 1945 and 1975. The recent development of well-tolerated and highly effective therapies for chronic HCV infection represents a unique opportunity to dramatically reduce rates of HCV-related complications and their costs. Critical to the introduction of such therapies will be well-designed provincial programming to ensure immediate treatment access to individuals at highest risk for complication, and well-defined strategies to address the global treatment needs of traditionally high-risk and marginalized populations. HCV practitioners in New Brunswick created a provincial strategy that stratifies treatment according to those at highest need, measures clinical impact, and creates evaluation strategies to demonstrate the significant direct and indirect cost savings anticipated with curative treatments.

Objective: Low CD4/CD8 T-cell ratios occur in conditions associated with reduced immune resilience, including older age and HIV infection. Effective antiretroviral therapy increases CD4/CD8 T-cell ratios, but often not to preinfection levels. The reasons for this deficit remain unclear. As cytomegalovirus (CMV) infection exacerbates falling CD4/CD8 T-cell ratios and immune senescence in the old elderly population, we investigated whether CMV infection is associated with refractory inversion of CD4/CD8 T-cell ratios and increased phenotypic evidence of immune senescence in HIV infection., Design: An observational cohort study of HIV-infected individuals attending the Newfoundland and Labrador Provincial HIV Clinic in St. John's., Methods: CMV infection status was determined by ELISA with infected cell lysate. Expression of CD28 and CD57 on CD8 T cells and cellular immune responses against CMV were measured by flow cytometry. We compared CD4/CD8 T-cell ratios, percentage of CD8 T cells expressing CD28 and percentage of CD8 T cells expressing CD57 between groups of HIV-infected persons discordant for CMV infection., Results: The CMV-seronegative group had significantly higher CD4/CD8 T-cell ratios, more frequent normalization of the ratio to at least 1, and lesser phenotypic evidence of immune senescence., Conclusion: CMV infection is associated with reduced immune reconstitution in HIV infection, even with suppression of HIV replication below detectable levels. This suggests that CMV infection, or some related factor, influences immune resilience in the setting of HIV infection.

Patients coinfected with HIV and hepatitis C virus (HCV) have poor to modest rates of response with interferon-based therapies, which remain a backbone of the treatment in HIV/HCV-coinfected patients. The mechanisms responsible for poor responsiveness to interferon are not well described. In this study a targeted proteomic analysis of plasma from 42 patients infected with both HIV and HCV and undergoing therapy for HCV with peginterferon and ribavirin was performed. Higher baseline plasma levels of interleukin (IL)-23 were associated with sustained virologic response. Further investigation of how IL-23 facilitates interferon (IFN) responsiveness, as evidenced by a >2-fold increase in most interferon-stimulated genes (ISGs), revealed that IL-23 indirectly enhances IFN signaling in peripheral blood mononuclear cells and HCV continuous culture system by preventing the down-regulation of the IFNAR2 receptor after exposure to IFN-α. These findings suggest a unique role of the IL-23 pathway in enhancing host response to type I interferons, thereby facilitating eradication of HCV. Low levels of IL-23 present in plasma of nonresponders may reflect an impaired immune state that in the case of HIV/HCV-coinfected subjects could potentially lead to disruption of TH17 CD4(+) T cells. This study suggests a major role for HIV-associated immune dysregulation present in HIV-infected subjects that subsequently determines the overall responsiveness to exogenous interferon-α-based HCV therapy.

Importance: The efficacy of directly acting antiviral agents in interferon-free regimens for the treatment of chronic hepatitis C infections needs to be evaluated in different populations., Objective: To determine the efficacy and safety of sofosbuvir with weight-based or low-dose ribavirin among a population with unfavorable treatment characteristics., Design, Setting, and Patients: Single-center, randomized, 2-part, open-label phase 2 study involving 60 treatment-naive patients with hepatitis C virus (HCV) genotype 1 enrolled at the National Institutes of Health (October 2011-April 2012)., Interventions: In the study's first part, 10 participants with early to moderate liver fibrosis were treated with 400 mg/d of sofosbuvir and weight-based ribavirin for 24 weeks. In the second part, 50 participants with all stages of liver fibrosis were randomized 1:1 to receive 400 mg of sofosbuvir with either weight-based or low-dose 600 mg/d of ribavirin for 24 weeks., Main Outcomes and Measures: The primary study end point was the proportion of participants with undetectable HCV viral load 24 weeks after treatment completion (sustained virologic response of 24 weeks [SVR24])., Results: In the first part of the study, 9 participants (90%; 95% CI, 55%-100%) achieved SVR24. In the second part, 7 participants (28%) in the weight-based group and 10 (40%) in the low-dose group relapsed after treatment completion leading to SVR24 rates of 68% (95% CI, 46%-85%) in the weight-based group and 48% (95% CI, 28%-69%; P = .20) in the low-dose group. Twenty individuals participated in a pharmacokinetic-viral kinetic substudy, which demonstrated a slower loss rate of infectious virus in relapsers than in participants who achieved SVR (clearance, 3.57/d vs 5.60/d; P = .009). The most frequent adverse events were headache, anemia, fatigue, and nausea. There were 7 grade 3 events including anemia, neutropenia, nausea, hypophosphatemia, and cholelithiasis or pancreatitis. No one discontinued treatment due to adverse events., Conclusion and Relevance: In a population of patients with a high prevalence of unfavorable traditional predictors of treatment response, a 24-week regimen of sofosbuvir and weight-based or low-dose ribavirin resulted in SVR24 rates of 68% and 48%, respectively., Trial Registration: clinicaltrials.gov Identifier: NCT01441180.

Background: Influenza infection may be more serious in human immunodeficiency virus (HIV)-infected individuals, therefore, vaccination against seasonal and pandemic strains is highly advised. Seasonal influenza vaccines have had no significant negative effects in well controlled HIV infection, but the impact of adjuvanted pandemic A/California/07/2009 H1N1 influenza hemaglutinin (HA) vaccine, which was used for the first time in the Canadian population as an authorized vaccine in autumn 2009, has not been extensively studied., Objective: Assess vaccine-related effects on CD4(+) T cell counts and humoral responses to the vaccine in individuals attending the Newfoundland and Labrador Provincial HIV clinic., Methods: A single dose of Arepanrix™ split vaccine including 3.75 μg A/California/07/2009 H1N1 HA antigen and ASO3 adjuvant was administered to 81 HIV-infected individuals by intramuscular injection. Plasma samples from shortly before, and 1-5 months after vaccination were collected from 80/81 individuals to assess humoral anti-H1N1 HA responses using a sensitive microbead-based array assay. Data on CD4(+) T cell counts, plasma viral load, antiretroviral therapy and patient age were collected from clinical records of 81 individuals., Results: Overall, 36/80 responded to vaccination either by seroconversion to H1N1 HA or with a clear increase in anti-H1N1 HA antibody levels. Approximately 1/3 (28/80) had pre-existing anti-H1N1 HA antibodies and were more likely to respond to vaccination (22/28). Responders had higher baseline CD4(+) T cell counts and responders without pre-existing antibodies against H1N1 HA were younger than either non-responders or responders with pre-existing antibodies. Compared to changes in their CD4(+) T cell counts observed over a similar time period one year later, vaccine recipients displayed a minor, transient fall in CD4(+) T cell numbers, which was greater amongst responders., Conclusions: We observed low response rates to the 2009 pandemic influenza vaccine among HIV-infected individuals without pre-existing antibodies against H1N1 HA and a minor transient fall in CD4(+) T cell numbers, which was accentuated in responders. A single injection of the Arepanrix™ pandemic A/California/07/2009 H1N1 HA split vaccine may be insufficient to induce protective immunity in HIV-infected individuals without pre-existing anti-H1N1 HA responses.

Before the advent of antiretroviral therapy (ART), CMV retinitis was a common, debilitating opportunistic infection in the HIV-infected population. ART has had such a favorable impact on the prevention and management of CMV retinitis that it can be considered in some ways to be CMV therapy. Currently available CMV directed antiviral therapies are quite successful at limiting vision loss, but in resource limited settings there is still significant morbidity associated with the disease. This review summarizes the pathology, diagnosis, clinical course and treatment of retinitis in the pre-ART era to provide context for the contemporary clinical scenario, and highlights current management strategies. Important questions concerning host correlates of susceptibility and ideal therapy in the context of drug resistance are also briefly reviewed.

The success of highly active antiretroviral therapy in preventing progression of HIV-infected individuals to AIDS has greatly reduced the burden of opportunistic infections. Individuals with HIV infection are living longer, but as a group are at greater risk to develop age-related disorders, such as certain cancers, cardiovascular disease, type II diabetes, and cognitive impairment, at earlier ages than non-HIV-infected persons. This premature susceptibility to age-related morbidities reflects a syndrome referred to as accelerated aging, wherein deleterious features associated with aging emerge decades earlier in the setting of chronic HIV infection. A prominent immunological feature of accelerated aging in HIV infection is inflation of cytomegalovirus-specific memory T-cell responses to levels associated with an immune risk phenotype. In the absence of HIV infection, immune risk phenotypes develop in cytomegalovirus-infected octogenarians and signify some degree of immune senescence and an elevated risk for all-cause mortality. Chronic inflammation is a probable factor in health risks conveyed by the immune risk phenotype and in putative relationships between cytomegalovirus infection and the same set of age-related disorders arising in chronic HIV infection. Most HIV-infected individuals are cytomegalovirus-seropositive, both HIV and cytomegalovirus are associated with inflammation-related morbidities, and HIV infection accelerates the development of cytomegalovirus-dependent immunological abnormalities. Therefore, closer investigation of the relationship between cytomegalovirus and age-related morbidities emerging in chronic HIV infection appears warranted. This review summarizes evidence that cytomegalovirus could be an important cofactor in the development of age-related morbidities in HIV infection and discusses research to address underlying mechanisms.

We investigated whether interferon-inducible genes (IFIGs) with known anti-human immunodeficiency virus (HIV) activity in vitro were associated with in vivo virological response in HIV infection. Nine untreated HIV-1-infected volunteers were treated for 12 weeks with peginterferon alfa-2a. A subset of IFIGs (23 of 47) increased compared with baseline through 6 weeks beyond therapy, and 10 of the 23 IFIGs significantly inversely correlated (r = -0.7; P < .05) with virological response. The strength of peginterferon alfa-2a-induced IFIG response significantly correlated with declines in HIV load during treatment (r(2) = 0.87, p = .003). This study links HIV virological response to a specific IFIG subset, a potential prognostic indicator in peginterferon alfa-2a-treated patients with HIV infection.

Antibodies against different chronic viruses, including hepatitis C virus (HCV), express a public cross-reactive idiotype (Id) designated as 1F7. The prominence of this Id may reflect selective engagement of B1 B cells by chronic pathogens. We investigated this by comparing 1F7 Id expression on CD5(+) and CD5(-) B cells, total IgG, total IgM and anti-HCV core antibodies in different HCV exposure settings. By flow cytometry, we observed a selective increase in 1F7 Id(+)CD5(+) B cells in chronic HCV infection. 1F7 Id levels in different immunoglobulin compartments were measured by enzyme-linked immunosorbent assay. 1F7 Id expression was prominent in anti-HCV core antibodies of approximately 90% of 141 HCV-exposed individuals tested. In the Canadian and Armenian study groups, participants who spontaneously cleared HCV infection had lower median 1F7 Id levels on total plasma IgG and anti-HCV core antibodies. Armenian spontaneous clearers, who were younger and more recently infected than their Canadian counterparts, also had had lower median 1F7 Id levels on total plasma IgM. Engagement by HCV of B-cell receptors within, or overlapping with the CD5(+) B1 B-cell repertoire is reflected in the production of 1F7 Id(+) anti-HCV antibodies and expansion of 1F7 Id(+)CD5(+) B cells. Higher 1F7 Id expression levels are associated with chronic infection.

Background: Multiple immune evasion strategies by which HCV establishes chronic infection have been proposed, including manipulation of cytokine responses. Prior infection with HIV increases the likelihood of chronic HCV infection and accelerates development of HCV-related morbidity. Therefore, we investigated in vitro cytokine responses to HCV structural and non-structural proteins in peripheral blood mononuclear cells (PBMC) from uninfected, HIV-infected, HCV-infected and HIV/HCV-coinfected individuals., Results: Intracellular flow cytometry was used to assess IL-2, IL-10, IL-12, and IFN-gamma production by freshly isolated PBMC incubated for 16 hours with recombinant HCV core, non-structural protein 3 (NS3), and NS4 proteins. Anti-HCV cellular responses were assessed in HIV/HCV-coinfected individuals by 3H-thymidine proliferation assay. Exposure to HCV antigens increased IL-10 production by PBMC, especially in uninfected and HIV-monoinfected individuals. This IL-10 response was attenuated in chronic HCV infection even with HCV/HIV-coinfection. The cells producing IL-10 in response to HCV proteins in vitro matched a PBMC subset recently shown to constitutively produce IL-10 in vivo. This subset was found at similar frequencies in uninfected, HIV-infected, HCV-infected and HIV/HCV-coinfected individuals before exposure to HCV proteins. HCV-specific T cell proliferation was detectable in only one HIV/HCV-coinfected individual who demonstrated no HCV-induced IL-10 response., Conclusion: This pattern suggests that selective induction of IL-10 in uninfected individuals and especially in HIV-monoinfected individuals plays a role in establishing chronic HCV infection and conversely, that attenuation of this response, once chronic infection is established, favours development of hepatic immunopathology.

The impact of immune regulatory imbalance covers surprising physiological breadth. Although dominance of anti-inflammatory cytokines such as IL-10 is associated with reduced immune responsiveness and susceptibility to persistent infection, conditions such as cardiovascular disease and diabetes are linked to chronic inflammation and lower IL-10 levels. An appropriate threshold for immune activation is critical for optimal protection from infection and conversely, from short- and long-term side-effects of immune effector mechanisms. To assess the possibility that IL-10 plays a role in setting this threshold and that healthy maintenance of immune silence may involve low-level immune suppression, we sought out and characterized human peripheral blood cells constitutively producing the immunosuppressive cytokine IL-10. We determined the surface phenotype of circulating PBMC constitutively producing IL-10 by surface and intracellular flow cytometry and visualized their ultrastructure by electron microscopy. The frequency of IL-10-producing and -secreting cells was estimated by ELISPOT and flow cytometry. Up to 1% of PBMC constitutively produce IL-10. These CD14(-)CD36(+)CD61(+) nonadherent cells expressed general markers of hematopoietic and progenitor cells (CD45 and CD7) but no stem cell, T cell, B cell, NK cell, monocytes or dendritic cell markers. Inflammation-associated TLRs were also absent. The IL-10-producing cells had prominent nuclei, multiple mitochondria, and abundant rough endoplasmic reticulum. Healthy individuals have PBMC constitutively producing IL-10. Although the lineage of these cells remains unclear, their properties and frequency suggest a potential role in homeostatic or innate immune suppression.

Objective: To identify factors associated with loss of in vitro stimulated anti-HIV cytotoxic T lymphocyte (CTL) activity., Methods: Immunological, virological and other characteristics of individuals who sustained anti-HIV CTL activity for prolonged periods with viral replication suppressed below detectable levels were compared with those that lost anti-HIV CTL activity under the same circumstances. Forty-four individuals, all but one receiving highly active antiretroviral therapy or combination therapy, were followed for 56 months. Virus load, lymphocyte counts, CD28 expression on CD8 T cells, in vitro restimulated HIV-specific CTL and T cell proliferation were assessed at regular intervals., Results: Anti-HIV CTL responses were maintained throughout by 20 individuals with consistently detectable HIV replication and in 17 of 24 individuals with sustained suppression of HIV replication. As a group, the seven who lost anti-HIV CTL were older, had weaker baseline anti-HIV CTL activity, higher historical virus loads, lower historical and contemporary CD4 T cell counts and a lower percentage of CD8 T cells expressing CD28. Multivariate analysis suggested that CD4 T cell counts and anti-HIV CTL amplitude at study onset were independently associated with CTL loss in these individuals, as was percentage of CD8 T cells expressing CD28 at study's end. There was a significant direct correlation between nadir CD4 T cell counts and duration of anti-HIV CTL persistence after suppression of viral replication., Conclusions: Most HIV-infected individuals retain CD8 anti-HIV CTL with in vitro proliferative potential, even when antigen is limited. Those who lose HIV-specific CTL responses generally show past or current evidence of severe disease progression or activity.

The extent to which highly active antiretroviral therapy (HAART) restores human immunodeficiency virus (HIV)-specific immunity in advanced infection is unknown. Therefore, we studied how effective therapy affected HIV-specific CD8(+) T cell responses in 4 individuals who had progressed to advanced infection. CD8(+) T cell responses were assessed by cytotoxicity and interferon-gamma (IFN-gamma) production. Proliferative CD4(+) T cell responses against HIV, Candida and mitogen were measured by (3)H-thymidine incorporation. Substantial immune reconstitution indicated by increased CD4(+) and CD8(+) T cell numbers followed suppression of viral replication. This was associated with emergence of HIV-specific cytotoxic T lymphocytes (CTL), but only concurrent with detectable viral replication. Emergent anti-HIV CTL were similar to those at earlier stages of infection in terms of their specificity, function, and CD28 phenotype. However, they were very short-lived in the absence of detectable HIV replication. Antigen-specific CD4(+) T cell responses remained severely compromised. Thus, effective antiretroviral therapy restores the capacity for HIV-specific CTL responses after advanced infection. However, the transient nature of these responses suggests failure to generate stable long-lived memory cells in the absence of HIV-specific helper T cell responses.