Anti-SARS-CoV-2 Neutralizing Responses in Various Populations: Use of a Rapid Surrogate Lateral Flow Assay and Correlations with Anti-RBD Antibody Levels.

BACKGROUND: After the global COVID-19 crisis, understanding post-infectious immunity and vaccine efficacy remains crucial. This study aims to assess anti-SARS-CoV-2 immunity through a quantitative analysis of anti-receptor-binding domain (RBD) antibodies and rapid functional testing of the neutralizing humoral response. METHODS: A retrospective analysis was conducted on samples from various cohorts, including partially vaccinated, fully vaccinated, post-COVID/no-vaccination, and post-COVID/vaccination individuals with various immune-competency statuses. The anti-RBD antibodies were measured using an automated chemiluminescence assay, while the neutralizing antibodies' (NAbs') activity was assessed through the lateral flow ichroma COVID-19 nAb test (LFT), a surrogate neutralization assay. RESULTS: The analysis revealed various levels of anti-RBD antibodies and seroneutralization responses across cohorts, with the post-COVID/vaccination group demonstrating the most robust protection. A correlation between anti-RBD antibodies and seroneutralization was observed, albeit with varying strength depending on the subgroup analyzed. Longitudinal assessment following natural infection showed an initial surge followed by a decline in both measures. A cutoff of 3.0 log10 BAU/mL was established to predict significant seroneutralization. CONCLUSIONS: The ichroma™ COVID-19 nAb test displayed high specificity and emerged as a valuable tool for monitoring anti-SARS-CoV-2 immunity. These findings contribute to understand the antibody response dynamics and underscore the potential of rapid tests in predicting protection against SARS-CoV-2 infection.

Does the ultrasensitive HBsAg Next assay enhance Hepatitis B diagnosis? An evaluation of analytical performances.

BACKGROUND: Accurate laboratory confirmation for Hepatitis B diagnosis and monitoring are crucial. Recently an ultrasensitive immunoassay test, the HBsAg Next (HBsAgNx), has been reported approximately eight times more sensitive than current HBsAg assays. The aim of our study was to assess the analytical performances of this new test. METHODOLOGY: 253 clinical samples from Saint Louis University Hospital were analyzed, splitted into four panels: (1) routine prospectively screening serums (n = 196), (2) retrospective serum samples before HBV reactivation (HBV-R) (n = 18), (3) occult HBV infection (OBI) (n = 10) and (4) a selection of wild type HBV genotypes (n = 29) RESULTS: Panel 1, showed robust agreement with the HBsAg Qualitative II (HBsAgQII) assay (Cohen's kappa = 0.83). Despite this agreement, 7 false positive with the HBsAgQII assay were found negative with HBsAgNx. One OBI was detected only with HBsAgNx. Panel 2 showed potential time savings in diagnosing HBV-R using HBsAgNx among 4/18 HBsAg positives samples. Panel 3 highlighted the ability of HBsAgNx to detect HBsAg in OBI patients defined by negative for HBsAg with HBsAgQII assay and positive for HBV DNA. Furthermore, the HBsAgNx assay detected all different genotypes. CONCLUSION: The study highlights the effectiveness of the HBsAgNx assay, showing its performance. It excels in detecting weakly positive samples and addressing challenging cases. HBsAgNx assay demonstrates promising analytical performances, with improved sensitivity and specificity compared to standard HBsAgQII assay, able to detect all genotypes. Its potential impact on early detecting and monitoring reactivations, and occult infections could be very useful in clinical practice.

Detection of SARS-CoV-2 in Saliva and Nasopharyngeal Swabs According to Viral Variants.

The genome of the Omicron variant of concern (VOC) contains more than 50 mutations, many of which have been associated with increased transmissibility, differing disease severity, and the potential to elute immune responses acquired after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination or infection with previous VOCs. Due to a better tropism for the upper respiratory tract, it was suggested that the detection of the Omicron variant could be preferred in saliva, compared to nasopharyngeal swabs (NPS). Our objective was to compare the SARS-CoV-2 levels in saliva fluid and NPS to estimated Ct values, according to the main SARS-CoV-2 variants circulating in France since the beginning of 2021. We analyzed 1,289 positive reverse transcription-polymerase chain reaction (RT-PCR) results during the three major waves: Alpha, Delta, and Omicron. NPS and saliva sampling were performed for 909 (71%) and 380 (29%) cases, respectively. The Ct values were significantly lower in the NPS samples than in the saliva samples for the three main VOCs. Still, the difference was less pronounced with the Omicron variant than for the Alpha and Delta variants. In contrast, in the saliva samples, Ct values were significantly lower for the Omicron variant than for the Delta (difference of -2.7 Ct) and the Alpha (difference of -3.0 Ct) variants, confirming a higher viral load in saliva. To conclude, the higher viral load in saliva was evidenced for the Omicron variant, compared to the Alpha and Delta variants, suggesting that established diagnostic methods might require revalidation with the emergence of novel variants. IMPORTANCE Established methods for SARS-CoV-2 diagnostics might require revalidation with the emergence of novel variants. This is important for screening strategy programs and for the investigation of the characteristics of new variants in terms of tropism modification and increased viral burden leading to its spread. SARS-CoV-2 RT-PCR screening on saliva samples reported lower but acceptable performance, compared to nasopharyngeal samples. Due to a better tropism for the upper respiratory tract, it was suggested that the detection of the Omicron variant could be preferred in saliva, compared to nasopharyngeal swabs. Our study analyzed 1,289 positive RT-PCR results during the three major waves in France: Alpha, Delta, and Omicron. Our findings also showed a higher viral load in saliva for the Omicron variant, compared to the Alpha and Delta variants.

[Aspects virologiques, diagnostic et variants du SARS-CoV-2]. / Virological aspects, diagnostic tools and variants of SARS-CoV-2.

VIROLOGICAL ASPECTS, DIAGNOSTIC TOOLS AND VARIANTS OF SARS-COV-2 SARS-CoV-2 is an enveloped non-segmented linear single-stranded positive RNA virus. The envelope carries the protein spike (S) which recognizes the ACE2 receptor on the target cell and allows entry of the virus. The numerous mutations on the S protein are at the origin of a great genetic diversity, involved in the species barrier and the escape from neutralizing antibodies. The main mode of transmission is respiratory. The virus replicates 24 hours after infection and the viral RNA is detected by direct diagnostic techniques as the reference technique is RT-PCR on a nasopharyngeal sample. To expand screening, RT-PCR on saliva samples and antigenic tests have been developed. The majority of patients develop specific antibodies within 10-15 days which are detectable by serological methods. It is recommended to combine the search for anti-N and anti-S antibodies. The viral genome has great plasticity and variants emerged from the summer of 2020. There are several classifications, including that of the WHO, which assigns each variant a Greek letter. Finally, Santé publique France has deployed an epidemiological surveillance system of variants using PCR screening and sequencing.

ASPECTS VIROLOGIQUES, DIAGNOSTIC ET VARIANTS DU SARS-COV-2 Le SARS-CoV-2 est un virus enveloppé à ARN monocaténaire linéaire non segmenté de polarité positive. L'enveloppe porte la protéine Spike (S) qui reconnaît le récepteur ACE2 sur la cellule cible et permet l'entrée du virus. Les nombreuses mutations sur la protéine S sont à l'origine d'une grande diversité génétique, impliquées dans le franchissement de la barrière d'espèce et l'échappement aux anticorps neutralisants. Le mode de transmission principal est respiratoire. Le virus réplique dès vingt-quatre heures après l'infection, et l'ARN viral est détecté par les techniques de diagnostic direct ; la technique de référence est la RT-PCR sur prélèvement nasopharyngé. Pour élargir le dépistage, la RT-PCR sur prélèvement salivaire et les tests antigéniques ont été développés. La majorité des patients développent des anticorps spécifiques en dix à quinze jours, qui sont détectables par les méthodes sérologiques ; il est recommandé de combiner la recherche des anticorps anti-N (nucléocapside) et anti-S. Le génome viral est doté d'une grande plasticité, et des variants ont émergé dès l'été 2020. Il en existe plusieurs classifications dont celle de l'Organisation mondiale de la santé qui attribue à chaque variant une lettre grecque. Enfin, Santé publique France a déployé un système de surveillance épidémiologique de ces variants à l'aide de techniques de criblage et de séquençage.

Humoral and cellular responses to SARS-CoV-2 BNT162b2 vaccination in allogeneic hematopoietic stem cell transplantation recipients.

Previous studies reporting the response to SARS-CoV-2 mRNA vaccination in alloHSCT recipients used serological and/or cellular assays, but no study has evaluated vaccine-induced neutralizing antibodies. We prospectively studied 28 alloHSCT recipients who received two BNT162b2 doses. Two patients groups were defined according to time from alloHSCT and immunosuppressive treatment, and had different baseline immunologic status. Study end-point was the evaluation of humoral and cellular responses one month after the second vaccine. All patients seroconverted. Anti-S IgG levels and neutralizing antibodies percentages were not significantly different between both groups. Using IFNγ ELISpot assay, five patients showed a strong increase, without correlation with the humoral response. Using flow cytometry lymphocyte proliferation assay, 14 patients exhibited responding T cells, without difference between both groups or correlation with anti-S IgG levels. A few low serological responders had a detectable CD4 + T cell proliferative response. This finding should be confirmed in a larger cohort.

Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence Among HIV-Negative Participants Using Tenofovir/Emtricitabine-Based Preexposure Prophylaxis in 2020: A Substudy of the French National Agency for Research on AIDS and Viral Hepatitis PREVENIR and Inserm SAPRIS-Sero Cohorts.

The potential preventive efficacy of tenofovir/emtricitabine on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was assessed in human immunodeficiency virus preexposure prophylaxis (PrEP) users. Prevalence of SARS-CoV-2 immunoglobulin G between May and October 2020 was similar in PrEP users and in a matched population-based cohort, suggesting that tenofovir/emtricitabine has no role in reducing the risk of SARS-CoV-2 acquisition.

Effect of Viral Replication and Liver Fibrosis on All-Cause Mortality in Human Immunodeficiency Virus-Hepatitis B Virus-Coinfected Individuals: A Retrospective Analysis of a 15-Year Longitudinal Cohort.

BACKGROUND: In individuals living with human immunodeficiency virus (HIV) and hepatitis B virus (HBV), widespread tenofovir (TDF)-containing antiretroviral therapy (ART) has led to substantial decreases in HBV-DNA and HIV-RNA detection. However, the links between viral replication, liver fibrosis, and mortality remain unclear. METHODS: A total of 300 individuals living with HIV-HBV and undergoing ART were prospectively followed. Virological and clinical data were obtained at baseline and every 6-12 months. We quantified the associations between HBV-DNA, HIV-RNA, and liver fibrosis with risk of all-cause mortality using a joint longitudinal survival model. Viral detection, viral loads, and time-averaged cumulative viral loads of HIV and HBV were modeled as 3 separate exposures. RESULTS: During a median of 10.5 years (interquartile range, 4.0-14.6), the proportion undergoing TDF-containing ART (baseline = 18.7%, end of follow-up = 79.1%) and with undetectable HBV-DNA (baseline = 36.7%, end of follow-up = 94.8%) substantially increased. 42 participants died (incidence rate = 1.30/100 person-years, 95% confidence interval [CI] = .96-1.76). The leading causes of death were non-AIDS/non-liver-related malignancies (28.6%), followed by liver-related (16.7%), AIDS-related (16.7%), and other (16.7%). All-cause mortality was associated with HBV-DNA viral load (adjusted hazards ratio [aHR] per log10 IU/mL = 1.41, 95% CI = 1.04-1.93, P = .03) or time-averaged cumulative HBV-DNA (aHR per log10 copy-years = 1.37, 95% CI = 1.03-1.83, P = .03), but not undetectable HBV-DNA. Advanced liver fibrosis at baseline was also associated with increased mortality rates (aHR = 2.35, 95% CI = 1.16-4.76, P = .02). No significant association between HIV-RNA replication and mortality was observed. CONCLUSIONS: Concurrent and historical HBV replication and liver fibrosis are important drivers of all-cause mortality in largely TDF-treated individuals living with HIV-HBV, despite one-fifth of deaths being liver-related. HBV-DNA and liver fibrosis remain important prognostic indicators for this patient population.

Persistent HBV replication and serological response during up to 15 years of tenofovir-based antiretroviral therapy in HIV/HBV-coinfected patients: a multicentre prospective cohort study.

OBJECTIVES: To determine the extent of hepatitis B virus (HBV) suppression and its association with seroclearance of hepatitis 'e' antigen (HBeAg) and hepatitis B surface antigen (HBsAg) in HIV/HBV-coinfected patients undergoing long-term tenofovir-based antiretroviral therapy (ART). METHODS: We prospectively followed 165 HIV/HBV-coinfected patients undergoing tenofovir-based ART. Serum HBV-DNA viral loads and HBeAg and HBsAg status were obtained at tenofovir initiation and every 6-12 months. We calculated the proportion achieving virological response (VR, <60 IU/mL) during follow-up. We also calculated rates of HBeAg- and HBsAg-seroclearance, which were compared between those who achieved versus never achieved VR during follow-up using an Exact binomial test. RESULTS: During a median 8.1 years (IQR = 4.0-13.2) of tenofovir treatment, 152 (92.1%) patients were able to achieve VR and 13 (7.9%) never achieved VR (median HBV-DNA at the end of follow-up = 608 IU/mL, range = 67-52 400 000). The prevalence of individuals with detectable HBV-DNA (≥60 IU/mL) decreased during tenofovir treatment: 15.1% (n = 14/93) at 5 years, 3.2% (n = 2/62) at 10 years and, 3.2% (n = 1/31) at 15 years. 44/96 HBeAg-positive patients (6.15/100 person-years) had HBeAg-seroclearance and 13/165 patients overall (0.87/100 person-years) had HBsAg-seroclearance. No difference in HBeAg-seroclearance was observed between those who achieved versus never achieved VR (7.4 versus 3.7/100 person-years, P = 0.33), while HBsAg-seroclearance was only observed in those with VR (1.0 versus 0/100 person-years, P = 0.49; respectively). Individuals with VR also had a higher frequency of undetectable HIV-RNA during treatment (P < 0.001). CONCLUSIONS: During long-term tenofovir-based ART for HIV/HBV coinfection, persistent HBV viraemia is apparent, but becomes less frequent over time. HBsAg-seroclearance only occurred in those with full HBV and relatively high HIV suppression.

Profiles of liver fibrosis evolution during long-term tenofovir treatment in HIV-positive patients coinfected with hepatitis B.

BACKGROUND & AIMS: Data on liver fibrosis evolution and its involvement in liver-related morbidity are scarce in individuals with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) co-infection during treatment. We identified profiles of liver fibrosis evolution in coinfected patients undergoing tenofovir (TDF). METHODS: We included 169 HIV-HBV-coinfected patients on TDF-based antiretroviral therapy. Virological and clinical data were obtained at TDF-initiation and every 6-12 months. From data on non-invasive liver fibrosis assessments collected yearly (FibroTest®), we established clusters of individuals with similar liver fibrosis evolution using group-based trajectory models. RESULTS: Four profiles of liver fibrosis evolution were established from a median follow-up of 7.6 years (IQR = 3.1-13.1): low fibrosis with no progression (29.6%, profile A), low fibrosis with progression (22.5%, profile B), moderate fibrosis with high fluctuation (39.6%, profile C), and cirrhosis with no regression (8.3%, profile D). When compared to profile A, baseline HBeAg-positive status was associated with profiles B (P = .007) and C (P = .004), older age with profiles C (P < .001) and D (P = .001), exposure to second-generation protease inhibitors with profile C (P = .004), and CD4+ <500/mm3 at the last visit with profiles C (P = .02) and D (P = .002). Incident liver-related events occurred in profiles other than A (B, n = 1/38; C, n = 6/67; D, n = 3/14) and all five cases of hepatocellular carcinoma occurred in profiles C (n = 2) and D (n = 3). CONCLUSIONS: TDF-treated HIV-HBV coinfected individuals do not seem to benefit from comparable levels of liver fibrosis regression as in HBV mono-infection. Liver-related morbidity occurs mainly in those with fluctuating or consistently high fibrosis levels.

Early virological response in six patients with hepatitis D virus infection and compensated cirrhosis treated with Bulevirtide in real-life.

Hepatitis delta virus (HDV) infection is the most severe form of viral hepatitis. Bulevirtide (BLV, Hepcludex® ) is an HDV/HBV entry inhibitor approved in June 2020 in the European Union for adult patients with chronic hepatitis delta (CHD) and compensated liver disease and positive HDV RNA viral load. This real-life preliminary report described early virological efficacy and safety of BLV in six patients with CHD and compensated liver disease: four patients were treated with the combination of BLV (2 mg/d in subcutaneous injection) and pegylated interferon (PEG-IFN) and two patients with BLV monotherapy. Four patients treated with combined therapy had a decline of a minimum of 1 log10 and 3/3 of 2 log10 of HDV-VL at 12 and 24 weeks, respectively. One patient among four had stopped the treatment at 12 weeks because of thrombocytopenia and an HDV-VL relapse was notified 24 weeks after treatment cessation. Three patients among four (3/4) had undetectable HDV-VL during the therapy (<100 IU/ml). One patient (1/2) treated with BLV monotherapy had a decline of HDV-VL by 1 log10 at 8 weeks and 1/1 by 2 log10 at 28 week on-treatment. Two patients among four (2/4) with combined therapy had normal ALT reached at 4 and 56 weeks. One patient (1/2) with BLV monotherapy achieves ALT normalization at​ 4 weeks on treatment. Hepatitis B surface antigen (HBsAg) levels remain unchanged. Three among six (3/6) patients had an elevation of total biliary acids without pruritus. These early data generated confirm the interest in this new treatment. Final results will be important to demonstrate long-term clinical benefit (fibrosis reversibility and reduction in hepato-cellular carcinoma [HCC]).

Performance of 30 commercial SARS-CoV-2 serology assays in testing symptomatic COVID-19 patients.

We report evaluation of 30 assays' (17 rapid tests (RDTs) and 13 automated/manual ELISA/CLIA assay (IAs)) clinical performances with 2594 sera collected from symptomatic patients with positive SARS-CoV-2 rRT-PCR on a respiratory sample, and 1996 pre-epidemic serum samples expected to be negative. Only 4 RDT and 3 IAs fitted both specificity (> 98%) and sensitivity (> 90%) criteria according to French recommendations. Serology may offer valuable information during COVID-19 pandemic, but inconsistent performances observed among the 30 commercial assays evaluated, which underlines the importance of independent evaluation before clinical implementation.

Analytical validation of hepatitis B core-related antigen (HBcrAg) using dried blood spots (DBS).

Limited access to nucleic acid testing (NAT) to quantify HBV DNA levels, an essential tool to determine anti-HBV treatment eligibility, represents a significant barrier to scale up HBV diagnostic services in resource-limited countries. Hepatitis B core-related antigen (HBcrAg) has the potential to become an affordable alternative because of its low cost (US$ <15/assay) and strong correlation with HBV DNA levels in treatment-naïve patients. However, the current assay requires plasma or serum. To further facilitate its application to decentralized settings, we developed and evaluated a standardized procedure to quantify HBcrAg using dried blood spots as a tool to diagnose HBV-infected people with high viraemia. We evaluated the following elution method optimized to quantify HBcrAg: suspension of a punched blood-soaked disc (11 mm) of Whatman 903 Protein Saver Card in 450 µL of PBS 0.05% Tween 20, followed by an incubation for 4 h at room temperature and a centrifugation at 10,000 g for 10 minutes. 150 µL of DBS eluate was used to quantify HBcrAg using chemiluminescent enzyme immunoassay (LUMIPULSE® G600II, Fujirebio). The limit of detection of dried blood spot HBcrAg in relation with HBV DNA levels was 19,115 IU/mL across the five major HBV genotypes (A/B/C/D/E). A strong linear correlation was confirmed between dried blood spot HBcrAg and HBV DNA levels (r = 0.94, p < 0.0001) in samples with high viral loads (range: 3.7-7.0 log IU/mL). The coefficient of variation ranged between 4.0-11.2% for repeatability and 3.9-12.2% for reproducibility. Analytical specificity was 100% (95% CI: 83.9-100%) in HBV-negative samples. Using our elution method, it may be possible to identify HBV-infected patients with high viraemia who need antiviral therapy using dried blood spot and HBcrAg. A large-scale clinical validation is warranted in resource-limited countries.

Higher risk of mortality in HIV-HBV co-infected patients from sub-Saharan Africa is observed at lower CD4+ cell counts.

BACKGROUND: Hepatitis B virus (HBV) co-infection in human immunodeficiency virus (HIV)-positive individuals increases the risk of overall mortality, especially when HBV DNA levels are high. The role of CD4+ cell counts in this association is poorly defined. We aimed to determine whether HIV-HBV co-infection influences changes in CD4+ cell count before and during antiretroviral therapy and whether it affects mortality risk at levels of CD4+. METHODS: 2052 HIV-positive participants from Côte d'Ivoire in a randomized-control trial assessing early or deferred ART were included. HBV-status was determined by hepatitis B surface antigen (HBsAg). Changes in CD4+ cell levels were estimated using a mixed-effect linear model. The incidence rates of all-cause mortality were estimated at CD4+ counts ≤350, 351-500, >500/mm3 and were compared between HBV-status groups as incidence rate ratios (IRR). RESULTS: At baseline, 190 (9%) were HBsAg-positive [135 (71%) with HBV DNA <2000 IU/mL, 55 (29%) ≥2000 IU/mL]. Follow-up was a median 58 months (IQR = 40-69). Between co-infection groups, there were no differences in CD4+ decline before ART initiation and no differences in CD4+ increase after ART initiation. After adjusting for sex, age, baseline HIV RNA level, and early/deferred ART arm, mortality rates were not significantly different between HBsAg-positive versus HBsAg-negative participants across strata of CD4+ levels. However, HBsAg-positive individuals with HBV-DNA ≥2000 IU/mL versus HBsAg-negative individuals had increased mortality rates at ≤350/mm3 (adjusted-IRR = 3.82, 95% CI = 1.11-9.70) and 351-500/mm3 (adjusted-IRR = 4.37, 95% CI = 0.98-13.02), but not >500/mm3 (adjusted-IRR = 1.07, 95% CI = 0.01-4.91). CONCLUSION: Despite no effect of HBV-infection on CD4+ levels, HIV-HBV co-infected individuals with high HBV replication are at higher risk of mortality when CD4+ is <500/mm3.

Interpretation of single target positivity among SARS-CoV-2 RT-PCR result tests.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently emerged and is responsible for coronavirus disease 19 (COVID-19). Diagnostic tests have been developed, mainly based on reverse-transcriptase PCR (RT-PCR). Most RT-PCR assays target at least two SARS-CoV-2 genes. In some cases, only one target gene is detected; the interpretation of such cases remains unclear. Objectives: Our objective was to analyse one target positive (OPT) RT-PCR results, using two RT-PCR assays: the Xpert® Xpress SARS-CoV-2 (Cepheid diagnosis, "Cepheid") and the Cobas® 6800 SARS-CoV-2 Test (Roche Molecular Diagnostics, "Roche"). Methods: All SARS-CoV-2 RT-PCR results performed on respiratory samples with the Roche or the Cepheid tests, from 23rd March to 6th August 2020 were collected. A patient with an OPT result was classified as "probable COVID-19" if they met at least one of the three following criteria: (i) history of a two gene-positive SARS-CoV-2 RT-PCR result, (ii) anti-SARS-CoV-2 antibody (IgG) detection or (iii) compatible chest computed tomography scan (CT-scan). Results: A total of 18,630 and 1189 SARS-CoV-2 RT-PCR tests were performed with the Roche and Cepheid tests, respectively. Among the positive SARS-CoV-2 RT-PCR, 293 samples - corresponding to 264 patients - were OPT (11% of the positive samples). Of these patients, 180 (68%) had at least one of the three criteria listed above and were classified as probable COVID-19. Conclusions: Sixty-eight percent of the patients with an OPT result were classified as probable COVID-19 and are probably at a late stage of infection. Serology and imaging can be helpful to confirm diagnosis.

Mortality in relation to hepatitis B virus (HBV) infection status among HIV-HBV co-infected patients in sub-Saharan Africa after immediate initiation of antiretroviral therapy.

It is unknown how past and active hepatitis B virus (HBV) infection affect immunorecovery and mortality in people with HIV who initiate tenofovir-based antiretroviral therapy (ART). Using data collected between 2008 and 2015, we studied people with HIV in sub-Saharan Africa initiating immediate ART in the Temprano randomized control trial. We classified participants into HBV groups at ART initiation: hepatitis B surface antigen (HBsAg)-positive with HBV DNA ≥ 2,000 IU/ml; HBsAg-positive with HBV DNA < 2,000 IU/ml; isolated HBcAb-positive; resolved infection (HBsAb-positive/HBcAb-positive); and HBV non-immune/vaccinated (HBcAb-negative). We compared square-root CD4-cell count increases using mixed-effect, non-linear regression adjusted for age, sex, baseline CD4 cell count, and HIV RNA. We compared all-cause mortality using Bayesian parametric survival regression. Among 879 participants, 24 (2.7%) had HBsAg with high HBV DNA, 76 (8.6%) HBsAg with low HBV DNA, 325 (37.0%) isolated anti-HBcAb, 226 (25.7%) resolved HBV infection and 228 (25.9%) HBV non-immune/vaccinated. We found no significant difference in CD4 cell increases between HBV-infection groups after adjustment (p = 0.16). Participants with HBsAg and high HBV DNA had the highest incidence of all-cause mortality (1.9/100 person-years, 95% Credibile Interval [CrI] = 1.0-3.4). By comparison, incidence rates of mortality were reduced by 57% (95%CrI = -79%, -13%), 60% (95%CrI = -82%, -12%) and 66% (95%CrI = -84%, -23%) in those who had isolated anti-HBcAb-positive, resolved HBV infection and HBV non-immune/vaccinated, respectively. In conclusion, individuals with HIV and past HBV infection or isolated anti-HBcAb-positive serology, much like HBV non-immune/vaccinated, experience lower mortality than those with HBsAg and high HBV DNA. Additional HBV-related management would not be necessary for these individuals.

Association of Hepatitis B Core-Related Antigen and Antihepatitis B Core Antibody With Liver Fibrosis Evolution in Human Immunodeficiency Virus-Hepatitis B Virus Coinfected Patients During Treatment With Tenofovir.

BACKGROUND: Quantitative hepatitis B core-related antigen (qHBcrAg) or antihepatitis B core antibody (qAnti-HBc) could be useful in monitoring liver fibrosis evolution during chronic hepatitis B virus (HBV) infection, yet it has not been assessed in human immunodeficiency virus (HIV)-HBV-coinfected patients undergoing treatment with tenofovir (TDF). METHODS: One hundred fifty-four HIV-HBV-infected patients initiating a TDF-containing antiretroviral regimen were prospectively followed. The qHBcrAg and qAnti-HBc and liver fibrosis assessment were collected every 6-12 months during TDF. Hazard ratios (HRs) assessing the association between qHBcrAg/qAnti-HBc and transitions from none/mild/significant fibrosis to advanced fibrosis/cirrhosis (progression) and from advanced fibrosis/cirrhosis to none/mild/significant fibrosis (regression) were estimated using a time-homogeneous Markov model. RESULTS: At baseline, advanced liver fibrosis/cirrhosis was observed in 40 (26%) patients. During a median follow-up of 48 months (interquartile range, 31-90), 38 transitions of progression (IR = 7/100 person-years) and 34 transitions of regression (IR = 6/100 person-years) were observed. Baseline levels of qHBcrAg and qAnti-HBc were not associated with liver fibrosis progression (adjusted-HR per log10 U/mL = 1.07, 95% confidence interval [CI] = 0.93-1.24; adjusted-HR per log10 Paul-Ehrlich-Institute [PEI] U/mL = 0.85, 95% CI = 0.70-1.04, respectively) or regression (adjusted-HR per log10 U/mL = 1.17, 95% CI = 0.95-1.46; adjusted-HR per log10 PEI U/mL = 0.97, 95% CI = 0.78-1.22, respectively) after adjusting for age, gender, duration of antiretroviral therapy, protease inhibitor-containing antiretroviral therapy, and CD4+/CD8+ ratio. Nevertheless, changes from the previous visit of qAnti-HBc levels were associated with liver fibrosis regression (adjusted-HR per log10 PEIU/mL change = 5.46, 95% CI = 1.56-19.16). CONCLUSIONS: Baseline qHBcrAg and qAnti-HBc levels are not associated with liver fibrosis evolution in TDF-treated HIV-HBV coinfected patients. The link between changes in qAnti-HBc levels during follow-up and liver fibrosis regression merits further study.

Correlation of serum hepatitis B core-related antigen with hepatitis B virus total intrahepatic DNA and covalently closed circular-DNA viral load in HIV-hepatitis B coinfection.

OBJECTIVE: To assess whether quantified hepatitis B core-related antigen (qHBcrAg) is a surrogate marker of intrahepatic replication in HIV and hepatitis B virus (HBV) coinfection. DESIGN: Cross-sectional study of 31 HIV-HBV-infected patients (total liver biopsies, n = 38) from a well defined cohort. METHODS: Spearman's rank correlation coefficients were calculated between qHBcrAg and intrahepatic markers of HBV replication [total intrahepatic-DNA, covalently closed circular (ccc) DNA, cccDNA : total intrahepatic-DNA ratio]. RESULTS: At biopsy, 22 (71.0%) patients were hepatitis B 'e' antigen (HBeAg)-positive, 22 (71.0%) had detectable plasma HBV-DNA, and 17 (54.8%) were treated with tenofovir. Median levels (interquartile range) of intrahepatic markers were as follows: HBV cccDNA (n = 34), 0.26 copies/cell (0.4-2.89); total intrahepatic-DNA (n = 38), 2.38 copies/cell (0.58-207.9), and cccDNA : total intrahepatic-DNA ratio (n = 34), 0.05 (interquartile range = 0.01-0.12). There was a significantly strong correlation between qHBcrAg and cccDNA in all patients (Rho = 0.65, P < 0.001), while a moderate correlation was observed between qHBcrAg and total intrahepatic-DNA (Rho = 0.57, P < 0.001) or cccDNA : total intrahepatic-DNA ratio (Rho = -0.45, P = 0.01). Similar findings were observed for HBeAg-positive patients and those with detectable HBV-DNA, with the exception of qHBcrAg and cccDNA or cccDNA : total intrahepatic-DNA ratio. In contrast, no significant correlation between qHBcrAg and any intrahepatic marker was observed in HBeAg-negative patients or those with undetectable HBV-DNA. No significant difference was observed in median qHBcrAg levels across liver fibrosis stages (P = 0.5). CONCLUSION: qHBcrAg is a potential surrogate marker of cccDNA in HIV-HBV coinfected patients, yet might be less useful with undetectable serum HBV-DNA or HBeAg-negative status. Whether qHBcrAg provides further clinical utility compared with other serological markers remains debatable.

A Hyper-Glycosylation of HBV Surface Antigen Correlates with HBsAg-Negativity at Immunosuppression-Driven HBV Reactivation in Vivo and Hinders HBsAg Recognition in Vitro.

Immune-suppression driven Hepatitis B Virus (HBV)-reactivation poses serious concerns since it occurs in several clinical settings and can result in severe forms of hepatitis. Previous studies showed that HBV strains, circulating in patients with HBV-reactivation, are characterized by an enrichment of immune-escape mutations in HBV surface antigen (HBsAg). Here, we focused on specific immune-escape mutations associated with the acquisition of N-linked glycosylation sites in HBsAg (NLGSs). In particular, we investigated profiles of NLGSs in 47 patients with immunosuppression-driven HBV-reactivation and we evaluated their impact on HBsAg-antigenicity and HBV-replication in vitro. At HBV-reactivation, despite a median serum HBV-DNA of 6.7 [5.3-8.0] logIU/mL, 23.4% of patients remained HBsAg-negative. HBsAg-negativity at HBV-reactivation correlated with the presence of >1 additional NLGSs (p < 0.001). These NLGSs are located in the major hydrophilic region of HBsAg (known to be the target of antibodies) and resulted from the single mutation T115N, T117N, T123N, N114ins, and from the triple mutant S113N+T131N+M133T. In vitro, NLGSs strongly alter HBsAg antigenic properties and recognition by antibodies used in assays for HBsAg-quantification without affecting HBsAg-secretion and other parameters of HBV-replication. In conclusion, additional NLGSs correlate with HBsAg-negativity despite HBV-reactivation, and hamper HBsAg-antigenicity in vitro, supporting the role of NGSs in immune-escape and the importance of HBV-DNA for a proper diagnosis of HBV-reactivation.

Automated quantification of Epstein-Barr virus in whole blood for post-transplant lymphoproliferative disorders monitoring.

BACKGROUND: Standardized and sensitive assays for Epstein Barr Virus (EBV) are needed to define universal cutoff for treatment initiation in allogeneic hematopoietic stem cells transplant recipients. In a context of accreditation and the availability of EBV international standard, we evaluated the Abbott RealTime EBV (RT) assay for EBV quantification in whole blood. METHODS: The RT assay was compared on 282 prospective clinical samples with the Artus EBV PCR Kit V1 assay (V1) and we analyzed the kinetics of EBV load in 11 patients receiving rituximab treatment. RESULTS: The estimated limit of detection was 88 IU/mL. The assay was linear (r2 = 0.9974) in the range of all samples tested (100 to 1,000,000 IU/mL). Intra-assay coefficients of variation (CV) ranged between 0.35 and 1.35%, and inter-assay CV between 3.40 and 4.5%. On samples above the limit of quantification, the two assays were strongly correlated. EBV RT values were on average 0.30 log10 IU/mL lower than those measured with the V1 assay. In patients treated with rituximab, the RT assay remained positive in 5 patients at the time it dropped below undetectable levels with the V1 assay. CONCLUSIONS: In conclusion, the RT assay is a reliable assay for EBV load in whole blood. Its sensitivity will enable to estimate the kinetics of EBV load and the impact of treatments to control EBV reactivations.