Abstract Background and Aim This study evaluates whether a stool donor program to supply fecal microbiota transplantation (FMT) product is feasible in the Australian regulatory environment. The primary outcome was capacity to supply FMT product. The secondary outcomes were donor eligibility, retention, and output. Methods Prospective observational cohort study using data collected from the stool donor and FMT production records from BiomeBank, South Australia. Participants were people who engaged with BiomeBank's donor screening and FMT manufacturing process between 01 January 2021 and 31 December 2021. Results In total 176 people registered interest in the program, 74 of 176 (42.0%) proceeded to written questionnaire, 14 of 176 (8.0%) underwent clinical assessment, and 8 of 176 (4.5%) enrolled in the program. Two people were ineligible based on laboratory tests: both had an extended spectrum beta‐lactamase producing organism in stool and one also tested positive for hepatitis B core antibody. Two donors remained eligible from 2020, resulting in 10 enrolled donors in 2021; 5 of 10 (50%) male with a median age of 36.9 years (interquartile range, 30.3–42.7 years). All donors were ineligible to donate at some time point. There were 144 stool donations processed into 1480 50 mL FMT; 413 FMT were shipped to 33 Australian hospitals for treatment, 470 for clinical trials, and 89 were destroyed prior to release from quarantine. Conclusion Recruitment into the program, retention, and maximizing the yield from a donation period was challenging. Despite this, BiomeBank was able to produce and supply FMT to Australian hospitals under the TGA‐regulated Class 2 Biologicals framework.

Background: Pegylated interferon (Peg-IFN) is recommended as first-line therapy for chronic hepatitis B (CHB) but has significant side effects and is rarely used compared to oral nucleos(t)ide analogues (NA). There are limited recent clinical efficacy or economic analysis data comparing approved CHB therapy in North America. Methods: This retrospective study examined clinical outcomes, off-treatment durability, and cost-effectiveness of Peg-IFN versus NA for CHB. Demographic (age, sex, ethnicity), clinical data (i.e., liver tests, hepatitis B virus DNA, serology, transient elastography) and documented side effects were collected by retrospective chart review of patients followed in the University of Calgary Liver Unit who received Peg-IFN therapy from January 2007 to December 2020. The cost-effectiveness of Peg-IFN versus NA therapy was modelled over a 10-year time horizon. Results: Sixty-eight CHB patients were treated with Peg-IFN (median age 45.65, 74% male, 84% Asian); 50/68 (74%) completed 48 weeks of treatment with a median follow-up of 6.54 years (interquartile range 5.07). At the last known follow-up, 23/68 (34%) have not required NA treatment and one had HBsAg loss; 27 have been started on NA. Predictors of obtaining a sustained virological response included being hepatitis B e antigen-negative at treatment end and a quantitative hepatitis B surface antigen <1000 IU/mL. Economic modelling showed that finite Peg-IFN was not cost-effective versus NA at a 10-year time horizon. Conclusions: PEG-IFN remains a potential treatment for CHB although there is a significant intolerance/failure rate. Using PEG-IFN based on patient preference is reasonable and optimal patient selection may improve treatment cost-effectiveness.

Background: Hepatitis B surface antigen (HBsAg) loss is associated with improved clinical outcomes for individuals with chronic hepatitis B (CHB); however, the effects of varying HBsAg levels on clinical outcomes in diverse cohorts are understudied. Methods: In this cross-sectional, multicentre, retrospective study, the data on adult subjects enrolled in the Canadian HBV Network with CHB seen from 1 January 2012 to 30 January 2021 with the treatment and virologic data within 1 year of HBsAg testing were analyzed. Patients were tested for HBsAg using qualitative (for HBsAg-negative samples) and/or commercial quantitative assays. Fibrosis or hepatic necroinflammation was determined by the liver stiffness measurement (LSM). The baseline data were summarized using descriptive statistics and compared by using univariable/multivariable analyses. Results: This study included 844 CHB patients, with a median age of 49.6 years (IQR 40.1–60.5), and 37% were female. In total, 751 patients (78.6%) had known ethnicity data, and 76.7% self-reported as Asian, 11.4% as Black, 6.8% as White, and 4.8% as other. Among the 844 patients, 237 (28.0%) were HBsAg (−) (1000 IU/mL. Overall, 80% (682) had known HBeAg status at the last follow-up, and the majority (87.0%) were HBeAg-negative. In addition, 54% (461/844) had prior antiviral therapy, 19.7% of which (16.3, 23.7, n = 91) were HBsAg (−). The treated patients had a lower risk of cirrhosis (16.46, 95% CI 1.89–143.39, p = 0.01) or HCC (8.23, 95% CI 1.01–67.39, p = 0.05) than the untreated patients. A lower proportion of the HBsAg-loss group had cirrhosis (5.7% vs. 10.9%, p = 0.021) and HCC (0.9% vs. 6.2%, p = 0.001). Conclusion: In this retrospective, ethnically diverse cohort study, CHB patients who received antiviral therapy and/or had HBsAg loss were less likely to develop cirrhosis and HCC, confirming the results of the studies in less diverse cohorts. No association was found between the qHBsAg level and fibrosis determined with LSM. Individuals who achieved HBsAg loss had low-level qHBsAg within 1 year of seroclearance.

Objective: Tenofovir alafenamide (TAF) achieves increased renal safety and improved alanine aminotransferase (ALT) normalization but increased lipid profile in hepatitis B virus (HBV)–monoinfected patients switched from tenofovir disoproxil fumarate (TDF). It is unclear whether HIV coinfection perturbs these biochemical changes. To this end, we assessed these parameters in HIV/HBV-coinfected patients switched from TDF to TAF. Design: Retrospective, multicenter, observational study. Methods: HIV/HBV-coinfected patients switched from TDF to TAF-based antiretroviral therapy (ART) at 6 Canadian Hepatitis B Network (CanHepB) academic sites were included. Changes in lipid profile, estimated glomerular filtration rate (eGFR), and ALT were evaluated using linear mixed effect model regression. Results: Eighty-two HIV/HBV-coinfected patients with a mean 103-week follow-up duration were identified. At time of TAF switch, 80 of 82 (98%) were HBV virally suppressed, 29 of 82 (35%) had elevated ALT levels, and 63 of 82 (77%) had eGFR of ≥60 mL/min per 1.73 m2. Twenty-six/Eighty-two (32%) had preexisting renal comorbidities. There were no changes in total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglyceride levels 2 years after TAF switch. Those with elevated ALT levels achieved greater ALT normalization after TAF switch (−0.004 [−0.008 to 0.0] log10U/L/mo, P = 0.03). eGFR decline rate while on TDF (−0.66 [−0.23 to −1.08] mL/min/month, P < 0.005) was diminished after switching to TAF (−0.02 [−0.16 to 0.11] mL/min/mo, P = 0.7) and those with eGFR of <60 mL/min experienced increase in eGFR after TAF switch (0.45 [0.03–0.87] mL/min/mo, P = 0.04). Conclusions: Our study supports switching from TDF to TAF with positive influence on overall long-term biochemical profile in HIV/HBV-coinfected individuals.

Background & Aims:HDV affects 4.5-13% of chronic hepatitis B (CHB) patients globally, yet the prevalence of HDV infection in Canada is unknown. To investigate the prevalence, genotype, demographics, and clinical characteristics of HDV in Canada, we conducted a retrospective analysis of (1) HDV antibody and RNA positivity among referred specimens, and (2) a cross-sectional subset study of 135 HDV seropositive +/-RNA (HDV+) patients compared with 5,132 HBV mono-infected patients in the Canadian HBV Network. Methods:Anti-HDV IgG-positive specimens collected between 2012 and 2019 were RNA tested and the genotype determined. Patients enrolled in the Canadian HBV Network were >18 years of age and HBsAg-positive. Clinical data collected included risk factors, demographics, comorbidities, treatment, fibrosis assessment, and hepatic complications. Results:Of the referred patients, 338/7,080 (4.8%, 95% CI 4.3-5.3) were HDV seropositive, with 219/338 RNA-positive (64.8%, 95% CI 59.6-69.7). The HDV+ cohort were more likely to be born in Canada, to be White or Black/African/Caribbean than Asian, and reporting high-risk behaviours, compared with HBV mono-infected patients. Cirrhosis, complications of end-stage liver disease, and liver transplantation were significantly more frequent in the HDV+ cohort. HDV viraemia was significantly associated with elevated liver transaminases and cirrhosis. Five HDV genotypes were observed among referred patients but no association between genotype and clinical outcome was detected within the HDV+ cohort. Conclusions:Nearly 5% of the Canadian HBV referral population is HDV seropositive. HDV infection is highly associated with risk behaviours and both domestic and foreign-born patients with CHB. HDV was significantly associated with progressive liver disease highlighting the need for increased screening and surveillance of HDV in Canada. Lay summary:Evidence of HDV infection was observed in approximately 5% of Canadians who were infected with HBV referred to medical specialists. HDV-positive patients were more likely to be male, born in Canada, or White or Black/African/Caribbean compared to Asian, and to have reported high-risk activities such as injection or intranasal drug use or high-risk sexual contact compared with patients infected with only HBV. Patients infected with HDV were also more likely to suffer severe liver disease, including liver cancer, compared with HBV mono-infected patients.

Background and Aims:The obesity epidemic has increased the risk of nonalcoholic fatty liver disease (NAFLD) in both the general and chronic hepatitis B (CHB) populations. Our study aims to determine the prevalence of NAFLD in patients with CHB based on controlled attenuation parameter (CAP) and the epidemiological, clinical, and virological factors associated with severe hepatic steatosis. Methods:The Canadian Hepatitis B Network cohort was utilized to provide a cross-sectional description of demographics, comorbidities, antiviral treatment, and hepatits B virus (HBV) tests. Liver fibrosis and steatosis were measured by transient elastography and CAP, respectively. Any grade and severe steatosis were defined as CAP >248 and >280 dB/m, respectively. Advanced liver fibrosis was defined as transient elastography measurement >10.7 kPa. Results:In 1178 patients with CHB (median age: 47.4%, 57.7% males, 75.7% Asian, 13% African, 6.5% White, 86% HBV e antigen negative, median HBV DNA of 2.44 log10IU/mL, 42.7% receiving treatment), the prevalence of any grade and severe steatosis was 53% and 36%, respectively. In the multivariate analysis, obesity was a significant predictor for severe steatosis (adjusted odds ratio: 5.046, 95% confidence interval: 1.22-20.93). Severe steatosis was a determinant associated with viral load (adjusted odds ratio: 0.385, 95% confidence interval: 0.20-0.75, P < .01; r = -0.096, P = .007) regardless of antiviral therapy, age, and alanine aminotransferase levels. Conclusion:In this large multiethnic CHB population, hepatic steatosis is common. Severe steatosis is independently associated with higher fibrosis, but negatively with HBV DNA, regardless of antiviral therapy history.

Tenofovir alafenamide fumarate (TAF) has high plasma stability resulting in fewer renal adverse events compared to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. We aimed to study the effectiveness and renal safety of TAF in a real‐world setting, in patients with or without compromised kidney function. CHB patients (Nucleos(t)ide Analogue [NA]‐naïve or experienced) who received TAF >1 year from 11 academic institutions as part of the Canadian Hepatitis B Network (CanHepB) were included. Kidney function was measured by estimated glomerular filtration rate (eGFR) as per Cockcroft‐Gault. Patients were followed for up to 160 weeks. Of 176 patients receiving TAF, 143 switched from NA (88% TDF), and 33(19%) were NA naïve. Majority of NA‐naïve patients (75%) achieved undetectable HBV DNA after one year of TAF treatment. Majority of patients with eGFR <60 mL/min who had renal deterioration during TDF (76%) reversed to eGFR increase after one year of TAF ( p =0.009). Among patients with stage 2 chronic kidney disease (CKD) (eGFR 60–89), the estimated eGFR decline during TDF was halted after switching to TAF ( p =0.09). NA‐experienced patients with abnormal ALT before TAF showed a significant decline after switching to TAF: −0.005 [−0.006 – −0.004] log 10 ULN U/L/month, p <0.001). In CHB patients, TAF was safe, well‐tolerated and effective in this real‐world cohort. Switching to TAF led to improved kidney function, particularly in those with stage 2 CKD, which suggests that the indication for TAF in the guidelines could be extended to patients with an eGFR higher than 60 mL/min.

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.

The Hepatitis B virus (HBV) affects over 250 million people worldwide and can lead to cirrhosis and hepatocellular carcinoma. HBV surface antigen (HBsAg) quantification is increasingly used to predict disease activity and treatment response. As there is no virologic cure, clinicians are seeking a “functional cure”, or HBsAg loss, as a guide to safely stopping nucleos(t)ide analogue therapy. Tenofovir Disoproxil Fumarate (TDF) and Entecavir (ETV) are first line therapy but require prolonged treatment to achieve HBsAg clearance. To assess the association between nucleos(t)ide therapy and decline in quantitative HBsAg (qHBsAg) in patients with HBV from Calgary, Alberta. A retrospective review of adult patients with chronic HBV, followed at the University of Calgary Liver Clinic, was conducted between January 2012 and October 2020. Patients were excluded if treatment was discontinued or changed, only had a single qHBsAg measurement, or were co-infected with hepatitis C virus, hepatitis delta virus, or HIV. Patients were stratified according to therapy with TDF, ETV, or no treatment. To identify associations between mean changes in qHBsAg by medication exposure, one-way ANOVAs and t-tests were performed. Results were reported as means and 95% confidence intervals (CI). The median time from initial qHBsAg to most-recent was calculated. 187 patients were included in the final analysis (Table 1). 77 were excluded for being on more than one medication over the study period, 10 were excluded due to discontinuation of treatment, and 195 were excluded for single qHBsAg measurements. The mean qHBsAg decline was -750.04 IU/mL (95% CI -1311.58, -188.50) in the TDF group (n=45) and -309.20 IU/mL (95% CI -600.90, -17.50) in the ETV group (n=35) (p=0.20). In the no treatment group (n=107), the mean qHBsAg increased by 711.29 IU/mL (95% CI -600.78, 2023.80)(Figure 1). The median time from initial qHBsAg to most-recent was 980 days. Quantitative HBsAg levels declined in patients on TDF and ETV, but increased in untreated patients. Although HBsAg levels showed a trend for greater decline in TDF-treated patients, results failed to reach statistical significance, and may be affected by overall treatment duration. Future studies will explore medication use as a time-varying covariate to identify how change in treatment influences changes in HBsAg over time. None

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.

Neural insults in conditions such as multiple sclerosis induce changes in the brain's extracellular matrix (ECM) that can inhibit myelin repair. In this Opinion article, Yong and colleagues examine such changes and how the ECM could be targeted to promote remyelination in disease.

BACKGROUND:Susceptibility-weighted imaging (SWI) is an iron-sensitive magnetic resonance imaging (MRI) method that has shown iron-related lesions in multiple sclerosis (MS) patients. The contribution of deoxyhemoglobin to the signals seen in SWI has not been well characterized in MS.OBJECTIVES:To determine if SWI lesions (seen as focal hypointensities) exist in the experimental autoimmune encephalomyelitis (EAE) animal model of MS, and to determine whether the lesions relate to iron deposits, inflammation, demyelination, and/or deoxyhemoglobin in the vasculature.METHODS:We performed SWI on the lumbar spinal cord and cerebellum of EAE and control mice (both complete Freund's adjuvant/pertussis toxin (CFA/PTX)-immunized and naive). We also performed SWI on mice before and after perfusion (to remove blood from vessels). SWI lesions were counted and their locations were compared to histology for iron, myelin and inflammation.RESULTS:SWI lesions were found to exist in the EAE model. Many lesions seen by SWI were not present after perfusion, especially at the grey/white matter boundary of the lumbar spinal cord and in the cerebellum, indicating that these lesion signals were associated with deoxyhemoglobin present in the lumen of vessels. We also observed SWI lesions in the white matter of the lumbar spinal cord that corresponded to iron deposition, inflammation and demyelination. In the cerebellum, SWI lesions were present in white matter tracts, where we found histological evidence of inflammatory perivascular cuffs.CONCLUSIONS:SWI lesions exist in EAE mice. Many lesions seen in SWI were a result of deoxyhemoglobin in the blood, and so may indicate areas of hypoxia. A smaller number of SWI lesions coincided with parenchymal iron, demyelination, and/or inflammation.

OBJECTIVE:Failure of remyelination is a critical impediment to recovery in multiple sclerosis (MS). Chondroitin sulfate proteoglycans (CSPGs) have been reported to accumulate in MS lesions, and we thus examined the functional roles of CSPGs on oligodendrocyte precursor cells (OPCs), oligodendrocytes, and remyelination.METHODS:We evaluated the expression of CSPGs in lysolecithin-injected mouse spinal cord, an animal model of demyelination and spontaneous remyelination. The functional impact of CSPGs on OPCs and remyelination was investigated using cultured adult murine and human OPCs and by treating demyelinated mice with xyloside to reduce the CSPG deposition that occurred following injury.RESULTS:Early and robust upregulation of CSPGs following lysolecithin-induced demyelination was cleared during remyelination. In culture, CSPGs anchored onto the substratum reduced the adhesion of mouse and human OPCs and their subsequent morphological differentiation into process-bearing oligodendrocytes. Soluble CSPGs added to already adherent OPCs reduced the development of processes, whereas the acquisition of mature myelin proteins was unimpeded. Stripe assays of alternating CSPG and control substrata confirmed the nonpermissive nature of CSPGs for OPC adhesion and morphological differentiation. Enzymatic degradation of CSPGs with chondroitinase ABC was sufficient to overcome CSPG-dependent inhibition of human oligodendrocytes. Finally, in vivo xyloside treatment to reduce CSPG synthesis in lysolecithin-demyelinated mice increased numbers of OPCs and oligodendrocytes in lesions, and culminated in improved remyelination.INTERPRETATION:These results identify CSPGs as a nonpermissive substrate for OPCs and oligodendrocytes, and as a prominent impediment to remyelination. The data suggest the requirement for the neutralization of CSPGs for repair after demyelination.

Phosphoinositide 3-kinase γ (PI3Kγ) consists of a catalytic subunit p110γ, which forms mutually exclusive dimers with one of the regulatory subunits called p101 and p84/p87(PIKAP). Recently, PI3Kγ emerged as being a potential oncogene because overexpression of the catalytic subunit p110γ or the regulatory subunit p101 leads to oncogenic cellular transformation and malignancy. However, the contribution of the individual subunits to tumor growth and metastasis and the mechanisms involved are not understood. We therefore individually knocked down the PI3Kγ subunits (p84, p101 and p110γ) in MDA-MB-231 cells, which reduced in vitro migration of the cell lines. Knockdown of p110γ or p101 inhibited apoptosis, Akt phosphorylation and lung colonization in SCID mice. Similarly, the knockdown of p110γ and p101 in murine epithelial carcinoma 4T1.2 cells inhibited primary tumor growth and spontaneous metastasis, as well as lung colonization. In contrast, knockdown of p84 in MDA-MB-231 cells enhanced Akt phosphorylation and lung colonization. These findings are the first to implicate differential functions of the two PI3Kγ regulatory subunits in the process of oncogenesis, and indicate that loss of p101 is sufficient to reduce in vivo tumor growth and metastasis to the same extent as that of p110γ.

The Class IA phosphoinositide 3-kinase delta (PI3Kδ) has been implicated in multiple signaling pathways involved in leukocyte activation and hence is an attractive target in many human autoimmune diseases, including multiple sclerosis (MS). Here, using mice expressing a catalytically inactive form of the PI3Kδ subunit p110δ, we show that signaling through PI3Kδ is required for full and sustained pathology of experimental autoimmune encephalomyelitis (EAE), a Th17-driven model of MS. In p110δ-inactivated mice, T cell activation and function during EAE was markedly reduced and fewer T cells were observed in the central nervous system (CNS). The decrease in T cell activation is unlikely to be due to defects in dendritic cell (DC) function, as p110δ-inactivated DCs migrate and present antigen normally. However, significant increases in the proportion of T cells undergoing apoptosis at early stages of EAE were evident in the absence of PI3Kδ activity. Furthermore, a profound defect in Th17 cellular responses during EAE was apparent in the absence of PI3Kδ activity while Th1 responses were less affected. A highly selective PI3Kδ inhibitor, IC87114, also had greater inhibitory effects on Th17 cell generation in vitro than it did on Th1 cell generation. Thus, PI3Kδ plays an important role in Th17 responses in EAE, suggesting that small molecule inhibitors of PI3Kδ may be useful therapeutics for treatment of MS and other autoimmune diseases.