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Background: Estrogen receptors occur in about two-thirds of breast tumors and endocrine therapy is probably the most important systemic therapy for hormone receptor positive breast cancer. However, after an initial response to hormonal therapy, most tumors develop resistance leading to disease progression. Central mechanisms thought to be involved in this process include: 1) alterations in tumor cell physiology causing insensitivity to drug-induced apoptosis or induction of drug-detoxifying mechanisms; 2) expression of energy-dependent transporters that eject anti-cancer drugs from cells and 3) the emergence of cancer stem-like cell clones that are estrogen-independent and/or antiestrogen resistant. We and others have shown that Notch signaling mediates survival signals in ER+ breast cancer cells; induces expression of drug transporter ABCG2 (BCRP), activates ERa in the absence of estrogen and mediates survival of breast cancer stem-like cells. Previously, we demonstrated a crosstalk between ERa and Notch signaling whereby estrogen inhibits Notch activation and estrogen withdrawal ortamoxifen re-activate Notch, a possible mechanism of resistance. The mechanism of these effects has remained elusive. Methods: we used sub-cellular fractionation and immunofluorescence staining to investigate the total expression and cellular distribution of Notch signaling components in MCF-7 cells treated with 17-p-estradiol, or estrogen-free medium. Results: Our data shows that in cells treated with estrogen-free medium, Notchi is located in the Lipid Rafts (LR) in the plasma membrane, along with Notch signaling components such as presenilin 1 (the catalytic subunit of γ-secretase), ADAM10 and Notch negative regulator NUMB. There is published evidence that γ-secretase is most active in lipid rafts. 17-p-Estradiol modifies the membrane lipid composition and change the localization of Notch and Notch regulators (such as ADAM10, presenilin-1 and NUMB) at the plasma membrane, thereby altering the activation of Notch. These observations are consistent with a model in which the lipid composition of the plasma membrane is a critical factor in regulating the rate of Notch activation. FDA-approved cholesterol lowering drugs affect Notch signaling in ways consistent with this model. Conclusions: Our findings indicate that endocrine therapy affects Notch signaling at least in part through alterations in membrane composition and lipid raft localization of Notch signaling components. [ABSTRACT FROM AUTHOR]

HIV-1 antiretroviral therapy is highly effective but fails to eliminate a reservoir of latent proviruses, leading to a requirement for life-long treatment. How the site of integration of authentic intact latent proviruses might impact their own or neighboring gene expression or reservoir dynamics is poorly understood. Here, we report on proviral and neighboring gene transcription at sites of intact latent HIV-1 integration in cultured T cells obtained directly from people living with HIV, as well as engineered primary T cells and cell lines. Proviral gene expression was correlated to the level of endogenous gene expression under resting but not activated conditions. Notably, latent proviral promoters were 100-10,000× less active than in productively infected cells and had little or no measurable impact on neighboring gene expression under resting or activated conditions. Thus, the site of integration has a dominant effect on the transcriptional activity of intact HIV-1 proviruses in the latent reservoir, thereby influencing cytopathic effects and proviral immune evasion., (© 2024 Teixeira et al.)

Introduction: To assess the effectiveness of novel HIV curative strategies, "cure" trials require periods of closely monitored antiretroviral therapy (ART) analytical treatment interruptions (ATIs). We performed a systematic review and meta-analysis to identify the impact of ATI with or without novel therapeutics in cure-related studies on the time to viral re-suppression following ART restart., Methods: Medline, Embase and Web of Science databases were searched for human studies involving ATIs from 1 January 2015 till 22 April 2024. The primary outcome was time to first viral re-suppression (plasma HIV viral load [VL] <50 copies/ml) stratified by receipt of interventional drug with ATI (IA) or ATI-only groups. Random-effects proportional meta-analysis and multivariable Cox proportional hazards analysis were performed using R., Results: Of 1073 studies screened, 13 were included that met the inclusion criteria with VL data available after restarting ART (n = 213 participants). There was no difference between time to viral suppression in IA or ATI-only cohorts (p = 0.22). For 87% of participants, viral suppression within 12 weeks of ART restart was achieved, and all eventually had at least one VL <50 copies/ml during follow-up. After adjusting for covariables, while participants in the IA cohort were associated with less rapid suppression (adjusted hazard ratio [aHR] 0.61, 95% CI 0.40-0.94, p = 0.026), other factors include greater log VL at ART restart (aHR 0.56, 95% CI 0.46-0.68, p<0.001), duration since HIV diagnosis (aHR 0.93, 95% CI 0.89-0.96) and longer intervals between HIV VL monitoring (aHR 0.66, 95% CI 0.59-0.74, p<0.001). However, the use of integrase inhibitors was associated with more rapid viral suppression (aHR 1.74, 95% CI 1.16-2.59)., Discussion: When designing studies involving ATIs, information on time to viral re-suppression after restarting ART is important to share with participants, and should be regularly monitored and reported, to assess the impact and safety of specific trial interventions in ATI studies., Conclusions: The majority of participants achieved viral suppression after restarting ART in ATI studies. ART regimens containing integrase inhibitors and frequent VL monitoring should be offered for people restarting ART after ATI studies to ensure rapid re-suppression., (© 2024 The Author(s). Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

Background: Outpatient COVID-19 monoclonal antibody (mAb) treatment via subcutaneous delivery, if effective, overcomes the logistical burdens of intravenous administration., Methods: ACTIV-2/A5401 was a randomized, masked placebo-controlled platform trial where participants with COVID-19 at low risk for progression were randomized 1:1 to subcutaneously administered BMS-986414 (C135-LS) 200 mg, plus BMS-986413 (C144-LS) 200 mg, (BMS mAbs), or placebo. Coprimary outcomes were time to symptom improvement through 28 days; nasopharyngeal SARS-CoV-2 RNA below the lower limit of quantification (LLoQ) on days 3, 7, or 14; and treatment-emergent grade 3 or higher adverse events (TEAEs) through 28 days., Results: A total of 211 participants (105 BMS mAbs and 106 placebo) initiated study product. Time to symptom improvement favored the active therapy but was not significant (median 8 vs 10 days, P =0.19). There was no significant difference in the proportion with SARS-CoV-2 RNA

Monoclonal antibodies are commonly engineered with an introduction of Met428Leu and Asn434Ser, known as the LS mutation, in the fragment crystallizable region to improve pharmacokinetic profiles. The LS mutation delays antibody clearance by enhancing binding affinity to the neonatal fragment crystallizable receptor found on endothelial cells. To characterize the LS mutation for monoclonal antibodies targeting HIV, we compared pharmacokinetic parameters between parental versus LS variants for five pairs of anti-HIV immunoglobin G1 monoclonal antibodies (VRC01/LS/VRC07-523LS, 3BNC117/LS, PGDM1400/LS PGT121/LS, 10-1074/LS), analyzing data from 16 clinical trials of 583 participants without HIV. We described serum concentrations of these monoclonal antibodies following intravenous or subcutaneous administration by an open two-compartment disposition, with first-order elimination from the central compartment using non-linear mixed effects pharmacokinetic models. We compared estimated pharmacokinetic parameters using the targeted maximum likelihood estimation method, accounting for participant differences. We observed lower clearance rate, central volume, and peripheral volume of distribution for all LS variants compared to parental monoclonal antibodies. LS monoclonal antibodies showed several improvements in pharmacokinetic parameters, including increases in the elimination half-life by 2.7- to 4.1-fold, the dose-normalized area-under-the-curve by 4.1- to 9.5-fold, and the predicted concentration at 4 weeks post-administration by 3.4- to 7.6-fold. Results suggest a favorable pharmacokinetic profile of LS variants regardless of HIV epitope specificity. Insights support lower dosages and/or less frequent dosing of LS variants to achieve similar levels of antibody exposure in future clinical applications.

The glycosylation of viral envelope proteins can play important roles in virus biology and immune evasion. The spike (S) glycoprotein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) includes 22 N-linked glycosylation sequons and 17 O-linked glycosites. We investigated the effect of individual glycosylation sites on SARS-CoV-2 S function in pseudotyped virus infection assays and on sensitivity to monoclonal and polyclonal neutralizing antibodies. In most cases, the removal of individual glycosylation sites decreased the infectiousness of the pseudotyped virus. For glycosylation mutants in the N-terminal domain and the receptor-binding domain (RBD), reduction in pseudotype infectivity was predicted by a commensurate reduction in the level of virion-incorporated S protein and reduced S trafficking to the cell surface. Notably, the presence of a glycan at position N343 within the RBD had diverse effects on neutralization by RBD-specific monoclonal antibodies cloned from convalescent individuals. The N343 glycan reduced the overall sensitivity to polyclonal antibodies in plasma from COVID-19 convalescent individuals, suggesting a role for SARS-CoV-2 S glycosylation in immune evasion. However, vaccination of convalescent individuals produced neutralizing activity that was resilient to the inhibitory effect of the N343 glycan.IMPORTANCEThe attachment of glycans to the spike proteins of viruses during their synthesis and movement through the secretory pathway can affect their properties. This study shows that the glycans attached to the severe acute respiratory syndrome coronavirus-2 spike protein enable its movement to the cell surface and incorporation into virus particles. Certain glycans, including one that is attached to asparagine 343 in the receptor-binding domain of the spike protein, can also affect virus neutralization by antibodies. This glycan can increase or decrease sensitivity to individual antibodies, likely through direct effects on antibody epitopes and modulation of spike conformation. However, the overall effect of the glycan in the context of the polyclonal mixture of antibodies in convalescent serum is to reduce neutralization sensitivity. Overall, this study highlights the complex effects of glycosylation on spike protein function and immune evasion., Competing Interests: The authors declare no conflict of interest.

Background: Coronary accessibility following redo-transcatheter aortic valve replacement (redo-TAVR) is increasingly important, particularly in younger low-risk patients. This study aimed to predict coronary accessibility after simulated Sapien-3 balloon-expandable valve implantation within an Evolut supra-annular, self-expanding valve using pre-TAVR computed tomography (CT) imaging., Methods: A total of 219 pre-TAVR CT scans from the Evolut Low-Risk CT substudy were analyzed. Virtual Evolut and Sapien-3 valves were sized using CT-based diameters. Two initial Evolut implant depths were analyzed, 3 and 5 mm. Coronary accessibility was evaluated for 2 Sapien-3 in Evolut implant positions: Sapien-3 outflow at Evolut node 4 and Evolut node 5., Results: With a 3-mm initial Evolut implant depth, suitable coronary access was predicted in 84% of patients with the Sapien-3 outflow at Evolut node 4, and in 31% of cases with the Sapien-3 outflow at Evolut node 5 ( P <0.001). Coronary accessibility improved with a 5-mm Evolut implant depth: 97% at node 4 and 65% at node 5 ( P <0.001). When comparing 3- to 5-mm Evolut implant depth, sinus sequestration was the lowest with Sapien-3 outflow at Evolut node 4 (13% versus 2%; P <0.001), and the highest at Evolut node 5 (61% versus 32%; P <0.001)., Conclusions: Coronary accessibility after Sapien-3 in Evolut redo-TAVR relates to the initial Evolut implant depth, the Sapien-3 outflow position within the Evolut, and the native annular anatomy. This CT-based quantitative analysis may provide useful information to inform and refine individualized preprocedural CT planning of the initial TAVR and guide lifetime management for future coronary access after redo-TAVR., Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02701283., Competing Interests: Disclosures Dr Tang is a physician proctor, consultant, and physician advisory board member for Medtronic, a consultant and physician advisory board member for Abbott Structural Heart, a consultant for NeoChord, and a physician advisory board member for JenaValve and Boston Scientific. He has received Speaker Honoraria for Siemens Healthineers and East End Medical. Dr Spencer is an employee and shareholder of Medtronic. Dr Rogers is a consultant and physician proctor to Edwards Lifesciences, Medtronic and Boston Scientific; is an Advisory Board member to Medtronic; has equity in Transmural Systems; and is a co-inventor on patents, assigned to National Institutes of Health, for transcatheter electrosurgery devices. Dr Grubb is a proctor, principal investigator and on the advisory board for Medtronic, serves on the advisory board or is a consultant for Ancora Heart, Boston Scientific, Abbott, 4C Medical, Gore, BioVentrix, and Edwards Lifesciences. Dr Gleason’s employer receives institutional grants and educational funding from Edwards Lifesciences, Abbott and Medtronic; he has no personal financial disclosures. Dr Gada has served as a consultant to Abbott, Bard Medical Corporation, Boston Scientific, Edwards Lifesciences, and Medtronic. Dr Mahoney is a proctor and consultant for Medtronic, Edwards, and Boston Scientific. Dr Dauerman is a consultant for Boston Scientific and Medtronic, and has received grant support from Boston Scientific and Medtronic. Dr Forrest has received grant support/research contracts and consultant fees/honoraria/speakers’ bureau fees from Edwards Lifesciences and Medtronic. Dr Reardon has received fees to his institution from Medtronic for consulting and providing educational services. Dr Blanke holds institutional research core laboratory agreements with Medtronic, Edwards Lifesciences, and Abbott with no personal compensation. Dr Leipsic holds institutional research core laboratory agreements with Medtronic, Edwards Lifesciences, Abbott, Boston Scientific, and Pi CARDIA with no personal compensation. Dr Abdel-Wahab’s institution receives speaker’s honoraria and consultancy fees on his behalf from Abbott, Boston Scientific, and Medtronic. Dr Attizzani is a consultant, serves as a proctor and is on the advisory board of Medtronic and is a consultant for Abbott Vascular. Dr Puri is a consultant, speaker and proctor for Medtronic, consults for Centerline Biomedical, Boston Scientific, Abbott, Philips, Products & Features, Shockwave Medical, VDyne, VahatiCor, Advanced Nanotherapies, NuevoSono, TherOx, GE Healthcare, BioVentrix, Protembis, and has equity interest in Centerline Biomedical, VahatiCor and NuevoSono. Dr Caskey reports proctor fees from Medtronic. Dr Chen is a proctor and is an advisory board member for Medtronic. Dr Allen has received grant support, proctor and speakers’ bureau fees from Edwards Lifesciences, Medtronic and Abbott with no personal compensation. Dr Chhatriwalla is a proctor for Edwards Lifesciences and Medtronic Inc, is on the speakers bureau for Abbott Vascular, Edwards Lifesciences and Medtronic Inc, and has a research grant from Boston Scientific. Dr Htun is a consultant for Medtronic. Dr Blackman is a proctor and consultant for Medtronic and Abbott Vascular, and a consultant for Edwards Lifesciences and Boston Scientific. Dr Tarantini has received lecture fees from Medtronic, Edwards Lifesciences, Abbott, and Boston Scientific. Dr Zhingre Sanchez is an employee and shareholder of Medtronic. Dr Popma is an employee and shareholder of Medtronic. Dr Sathananthan is a consulta nt to Edwards Lifesciences and Medtronic; and has received speaking fees from Edwards Lifesciences and NVT. The other authors report no conflicts.

Inducing antiretroviral therapy (ART)-free virological control is a critical step toward a human immunodeficiency virus type 1 (HIV-1) cure. In this phase 2a, placebo-controlled, double-blinded trial, 43 people (85% males) with HIV-1 on ART were randomized to (1) placebo/placebo, (2) lefitolimod (TLR9 agonist)/placebo, (3) placebo/broadly neutralizing anti-HIV-1 antibodies (bNAbs) or (4) lefitolimod/bNAb. ART interruption (ATI) started at week 3. Lefitolimod was administered once weekly for the first 8 weeks, and bNAbs were administered twice, 1 d before and 3 weeks after ATI. The primary endpoint was time to loss of virologic control after ATI. The median delay in time to loss of virologic control compared to the placebo/placebo group was 0.5 weeks (P = 0.49), 12.5 weeks (P = 0.003) and 9.5 weeks (P = 0.004) in the lefitolimod/placebo, placebo/bNAb and lefitolimod/bNAb groups, respectively. Among secondary endpoints, viral doubling time was slower for bNAb groups compared to non-bNAb groups, and the interventions were overall safe. We observed no added benefit of lefitolimod. Despite subtherapeutic plasma bNAb levels, 36% (4/11) in the placebo/bNAb group compared to 0% (0/10) in the placebo/placebo group maintained virologic control after the 25-week ATI. Although immunotherapy with lefitolimod did not lead to ART-free HIV-1 control, bNAbs may be important components in future HIV-1 curative strategies. ClinicalTrials.gov identifier: NCT03837756 ., (© 2023. The Author(s).)

Despite mRNA vaccination, elderly individuals remain especially vulnerable to severe consequences of SARS-CoV-2 infection. Here, we compare the memory B cell responses in a cohort of elderly and younger individuals who received mRNA booster vaccinations. Plasma neutralizing potency and breadth were similar between the two groups. By contrast, the absolute number of SARS-CoV-2-specific memory B cells was lower in the elderly. Antibody sequencing revealed that the SARS-CoV-2-specific elderly memory compartments were more clonal and less diverse. Notably, memory antibodies from the elderly preferentially targeted the ACE2-binding site on the RBD, while those from younger individuals targeted less accessible but more conserved epitopes. Nevertheless, individual memory antibodies elicited by booster vaccines in the elderly and younger individuals showed similar levels of neutralizing activity and breadth against SARS-CoV-2 variants. Thus, the relatively diminished protective effects of vaccination against serious disease in the elderly are associated with a smaller number of antigen-specific memory B cells that express altered antibody repertoires., (© 2023 Wang et al.)

Transaxillary access has been the most frequently used nonfemoral access route for transcatheter aortic valve replacement (TAVR) with a self-expanding valve. Use of transcarotid TAVR is increasing; however, comparative data on these methods are limited. We compared outcomes following transcarotid or transaxillary TAVR with a self-expanding, supra-annular valve., Methods: The Transcatheter Valve Therapy Registry was queried for TAVR procedures using transaxillary and transcarotid access between July 2015 and June 2021. Patients received a self-expanding Evolut R, PRO, or PRO + valve (Medtronic) and had 1-year follow-up. Thirty-day and 1-year outcomes were compared in transcarotid and transaxillary groups after 1:2 propensity score-matching. Multivariable regression models were fitted to identify predictors of key end points., Results: The propensity score-matched cohort included 576 patients receiving transcarotid and 1142 receiving transaxillary access. Median procedure time (99 vs 118 minutes; P  < .001) and hospital stay (2 vs 3 days; P  < .001) were shorter with transcarotid versus transaxillary access. At 30 days, patients with transcarotid access had similar mortality (Kaplan-Meier estimates 3.7% vs 4.3%, P  = .57) but significantly lower stroke (3.1% vs 5.9%; P  = .017) and mortality or stroke (6.0% vs 8.9%; P  = .033) compared with patients receiving transaxillary access. Similar differences were observed at 1 year. Transaxillary access was associated with increased risk of 30-day stroke (hazard ratio, 2.14; 95% confidence interval, 1.27-3.58) by multivariable regression analysis., Conclusions: Transcarotid versus transaxillary access for TAVR using a self-expanding valve is associated with procedural benefits and significantly lower stroke and mortality or stroke at 30 days. In patients with unsuitable femoral anatomy, transcarotid access may be the preferred delivery route for self-expanding valves., (© 2023 The Author(s).)

Waves of SARS-CoV-2 infection have resulted from the emergence of viral variants with neutralizing antibody resistance mutations. Simultaneously, repeated antigen exposure has generated affinity matured B cells, producing broadly neutralizing receptor binding domain (RBD)-specific antibodies with activity against emergent variants. To determine how SARS-CoV-2 might escape these antibodies, we subjected chimeric viruses encoding spike proteins from ancestral, BA.1 or BA.2 variants to selection by 40 broadly neutralizing antibodies. We identify numerous examples of epistasis, whereby in vitro selected and naturally occurring substitutions in RBD epitopes that do not confer antibody resistance in the Wuhan-Hu-1 spike, do so in BA.1 or BA.2 spikes. As few as 2 or 3 of these substitutions in the BA.5 spike, confer resistance to nearly all of the 40 broadly neutralizing antibodies, and substantial resistance to plasma from most individuals. Thus, epistasis facilitates the acquisition of resistance to antibodies that remained effective against early omicron variants., (© 2023. The Author(s).)

Feedback inhibition of humoral immunity by antibodies was first documented in 1909 1 . Subsequent studies showed that, depending on the context, antibodies can enhance or inhibit immune responses 2,3 . However, little is known about how pre-existing antibodies influence the development of memory B cells. Here we examined the memory B cell response in individuals who received two high-affinity anti-SARS-CoV-2 monoclonal antibodies and subsequently two doses of an mRNA vaccine 4-8 . We found that the recipients of the monoclonal antibodies produced antigen-binding and neutralizing titres that were only fractionally lower compared than in control individuals. However, the memory B cells of the individuals who received the monoclonal antibodies differed from those of control individuals in that they predominantly expressed low-affinity IgM antibodies that carried small numbers of somatic mutations and showed altered receptor binding domain (RBD) target specificity, consistent with epitope masking. Moreover, only 1 out of 77 anti-RBD memory antibodies tested neutralized the virus. The mechanism underlying these findings was examined in experiments in mice that showed that germinal centres formed in the presence of the same antibodies were dominated by low-affinity B cells. Our results indicate that pre-existing high-affinity antibodies bias germinal centre and memory B cell selection through two distinct mechanisms: (1) by lowering the activation threshold for B cells, thereby permitting abundant lower-affinity clones to participate in the immune response; and (2) through direct masking of their cognate epitopes. This may in part explain the shifting target profile of memory antibodies elicited by booster vaccinations 9 ., (© 2022. The Author(s).)

Individuals who receive a third mRNA vaccine dose show enhanced protection against severe COVID-19, but little is known about the impact of breakthrough infections on memory responses. Here, we examine the memory antibodies that develop after a third or fourth antigenic exposure by Delta or Omicron BA.1 infection, respectively. A third exposure to antigen by Delta breakthrough increases the number of memory B cells that produce antibodies with comparable potency and breadth to a third mRNA vaccine dose. A fourth antigenic exposure with Omicron BA.1 infection increased variant-specific plasma antibody and memory B cell responses. However, the fourth exposure did not increase the overall frequency of memory B cells or their general potency or breadth compared to a third mRNA vaccine dose. In conclusion, a third antigenic exposure by Delta infection elicits strain-specific memory responses and increases in the overall potency and breadth of the memory B cells. In contrast, the effects of a fourth antigenic exposure with Omicron BA.1 are limited to increased strain-specific memory with little effect on the potency or breadth of memory B cell antibodies. The results suggest that the effect of strain-specific boosting on memory B cell compartment may be limited., (© 2022 Wang et al.)

Attempts to reduce the human immunodeficiency virus type 1 (HIV-1) reservoir and induce antiretroviral therapy (ART)-free virologic control have largely been unsuccessful. In this phase 1b/2a, open-label, randomized controlled trial using a four-group factorial design, we investigated whether early intervention in newly diagnosed people with HIV-1 with a monoclonal anti-HIV-1 antibody with a CD4-binding site, 3BNC117, followed by a histone deacetylase inhibitor, romidepsin, shortly after ART initiation altered the course of HIV-1 infection ( NCT03041012 ). The trial was undertaken in five hospitals in Denmark and two hospitals in the United Kingdom. The coprimary endpoints were analysis of initial virus decay kinetics and changes in the frequency of CD4 + T cells containing intact HIV-1 provirus from baseline to day 365. Secondary endpoints included changes in the frequency of infected CD4 + T cells and virus-specific CD8 + T cell immunity from baseline to day 365, pre-ART plasma HIV-1 3BNC117 sensitivity, safety and tolerability, and time to loss of virologic control during a 12-week analytical ART interruption that started at day 400. In 55 newly diagnosed people (5 females and 50 males) with HIV-1 who received random allocation treatment, we found that early 3BNC117 treatment with or without romidepsin enhanced plasma HIV-1 RNA decay rates compared to ART only. Furthermore, 3BNC117 treatment accelerated clearance of infected cells compared to ART only. All groups had significant reductions in the frequency of CD4 + T cells containing intact HIV-1 provirus. At day 365, early 3BNC117 + romidepsin was associated with enhanced HIV-1 Gag-specific CD8 + T cell immunity compared to ART only. The observed virological and immunological effects of 3BNC117 were most pronounced in individuals whose pre-ART plasma HIV-1 envelope sequences were antibody sensitive. The results were not disaggregated by sex. Adverse events were mild to moderate and similar between the groups. During a 12-week analytical ART interruption among 20 participants, 3BNC117-treated individuals harboring sensitive viruses were significantly more likely to maintain ART-free virologic control than other participants. We conclude that 3BNC117 at ART initiation enhanced elimination of plasma viruses and infected cells, enhanced HIV-1-specific CD8 + immunity and was associated with sustained ART-free virologic control among persons with 3BNC117-sensitive virus. These findings strongly support interventions administered at the time of ART initiation as a strategy to limit long-term HIV-1 persistence., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

In simian-human immunodeficiency virus (SHIV)-infected non-human primates, broadly neutralizing antibodies (bNAbs) against the virus appear to stimulate T cell immunity. To determine whether this phenomenon also occurs in humans we measured HIV-1-specific cellular immunity longitudinally in individuals with HIV-1 starting antiviral therapy (ART) with or without adjunctive bNAb 3BNC117 treatment. Using the activation-induced marker (AIM) assay and interferon-γ release, we observe that frequencies of Pol- and Gag-specific CD8 + T cells, as well as Gag-induced interferon-γ responses, are significantly higher among individuals that received adjunctive 3BNC117 compared to ART-alone at 3 and 12 months after starting ART. The observed changes in cellular immunity were directly correlated to pre-treatment 3BNC117-sensitivity. Notably, increased HIV-1-specific immunity is associated with partial or complete ART-free virologic control during treatment interruption for up to 4 years. Our findings suggest that bNAb treatment at the time of ART initiation maintains HIV-1-specific CD8 + T cell responses that are associated with ART-free virologic control., (© 2022. The Author(s).)

The SARS-CoV-2 pandemic prompted a global vaccination effort and the development of numerous COVID-19 vaccines at an unprecedented scale and pace. As a result, current COVID-19 vaccination regimens comprise diverse vaccine modalities, immunogen combinations, and dosing intervals. Here, we compare vaccine-specific antibody and memory B cell responses following two-dose mRNA, single-dose Ad26.COV.2S, and two-dose ChAdOx1, or combination ChAdOx1/mRNA vaccination. Plasma-neutralizing activity, as well as the magnitude, clonal composition, and antibody maturation of the RBD-specific memory B cell compartments, showed substantial differences between the vaccination regimens. While individual monoclonal antibodies derived from memory B cells exhibited similar binding affinities and neutralizing potency against Wuhan-Hu-1 SARS-CoV-2, there were significant differences in epitope specificity and neutralizing breadth against viral variants of concern. Although the ChAdOx1 vaccine was inferior to mRNA and Ad26.COV.2S in several respects, biochemical and structural analyses revealed enrichment in a subgroup of memory B cell neutralizing antibodies with distinct RBD-binding properties resulting in remarkable potency and breadth., (© 2022 Wang et al.)

Background: Broadly neutralizing monoclonal antibodies (bNAbs) suppress HIV-1 RNA and may deplete residual viral reservoirs. We evaluated the safety and pharmacokinetics (PK) of dual intravenous VRC01LS and 10-1074 in very early-treated children with HIV-1 on suppressive antiretroviral treatment (ART)., Setting: Botswana., Methods: Children with HIV-1 (median age 3.1 years) on ART from <7 days old were enrolled. In phase A, 6 children received 10-1074 (30 mg/kg at day 0, 28, and 56) and 6 children received VRC01LS (30 mg/kg at day 0, 10 mg/kg at days 28 and 56) by intravenous infusion. In phase B, 6 children received the 2 bNAbs combined (with higher VRC01LS maintenance dose, 15 mg/kg) every 4 weeks for 32 weeks with PK evaluations over 8 weeks. Population PK models were developed to predict steady-state concentrations., Results: BNAb infusions were well tolerated. There were no infusion reactions nor any bNAb-related grade 3 or 4 events. The median (range) first dose Cmax and trough (day 28) combined from both phases were 1405 (876-1999) μg/mL and 133 (84-319) μg/mL for 10-1074 and 776 (559-846) μg/mL and 230 (158-294) μg/mL for VRC01LS. No large differences in bNAb clearances were observed when given in combination. The estimated VRC01LS half-life was shorter than in adults. Predicted steady-state troughs [median (90% prediction interval)] were 261 (95-565) and 266 (191-366) μg/mL for 10-1074 and VRC01LS, respectively, when given in combination., Conclusions: 10-1074 and VRC01LS were safe and well-tolerated among children receiving ART. Troughs exceeded minimal targets with every 4-week administration of 10-1074 at 30 mg/kg and VRC01LS at 15 mg/kg., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Antiretroviral therapy controls, but does not cure, HIV-1 infection due to a reservoir of rare CD4 + T cells harboring latent proviruses. Little is known about the transcriptional program of latent cells. Here, we report a strategy to enrich clones of latent cells carrying intact, replication-competent HIV-1 proviruses from blood based on their expression of unique T cell receptors. Latent cell enrichment enabled single-cell transcriptomic analysis of 1,050 CD4 + T cells belonging to expanded clones harboring intact HIV-1 proviruses from 6 different individuals. The analysis reveals that most of these cells are T effector memory cells that are enriched for expression of HLA-DR, HLA-DP, CD74, CCL5, granzymes A and K, cystatin F, LYAR, and DUSP2. We conclude that expanded clones of latent cells carrying intact HIV-1 proviruses persist preferentially in a distinct CD4 + T cell population, opening possibilities for eradication., Competing Interests: Declaration of interests Rockefeller University has patents on anti-HIV-1 antibodies 3BNC117 and 10-1074, on which M.C.N. is an inventor, that are licensed to Gilead., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Efforts to cure HIV have focused on reactivating latent proviruses to enable elimination by CD8 + cytotoxic T-cells. Clinical studies of latency reversing agents (LRA) in antiretroviral therapy (ART)-treated individuals have shown increases in HIV transcription, but without reductions in virologic measures, or evidence that HIV-specific CD8 + T-cells were productively engaged. Here, we show that the SARS-CoV-2 mRNA vaccine BNT162b2 activates the RIG-I/TLR - TNF - NFκb axis, resulting in transcription of HIV proviruses with minimal perturbations of T-cell activation and host transcription. T-cells specific for the early gene-product HIV-Nef uniquely increased in frequency and acquired effector function (granzyme-B) in ART-treated individuals following SARS-CoV-2 mRNA vaccination. These parameters of CD8 + T-cell induction correlated with significant decreases in cell-associated HIV mRNA, suggesting killing or suppression of cells transcribing HIV. Thus, we report the observation of an intervention-induced reduction in a measure of HIV persistence, accompanied by precise immune correlates, in ART-suppressed individuals. However, we did not observe significant depletions of intact proviruses, underscoring challenges to achieving (or measuring) HIV reservoir reductions. Overall, our results support prioritizing the measurement of granzyme-B-producing Nef-specific responses in latency reversal studies and add impetus to developing HIV-targeted mRNA therapeutic vaccines that leverage built-in LRA activity., (© 2022. The Author(s).)

The single-dose Ad.26.COV.2 (Janssen) vaccine elicits lower levels of neutralizing antibodies and shows more limited efficacy in protection against infection than either of the two available mRNA vaccines. In addition, Ad.26.COV.2 has been less effective in protection against severe disease during the Omicron surge. Here, we examined the memory B cell response to single-dose Ad.26.COV.2 vaccination. Compared with mRNA vaccines, Ad.26.COV.2 recipients had significantly lower numbers of RBD-specific memory B cells 1.5 or 6 mo after vaccination. Despite the lower numbers, the overall quality of the memory B cell responses appears to be similar, such that memory antibodies elicited by both vaccine types show comparable neutralizing potency against SARS-CoV-2 Wuhan-Hu-1, Delta, and Omicron BA.1 variants. The data help explain why boosting Ad.26.COV.2 vaccine recipients with mRNA vaccines is effective and why the Ad26.COV2.S vaccine can maintain some protective efficacy against severe disease during the Omicron surge., (© 2022 Cho et al.)

The Omicron variant of SARS-CoV-2 infected many vaccinated and convalescent individuals 1-3 . Despite the reduced protection from infection, individuals who received three doses of an mRNA vaccine were highly protected from more serious consequences of infection 4 . Here we examine the memory B cell repertoire in a longitudinal cohort of individuals receiving three mRNA vaccine doses 5,6 . We find that the third dose is accompanied by an increase in, and evolution of, receptor-binding domain (RBD)-specific memory B cells. The increase is due to expansion of memory B cell clones that were present after the second dose as well as the emergence of new clones. The antibodies encoded by these cells showed significantly increased potency and breadth when compared with antibodies obtained after the second dose. Notably, the increase in potency was especially evident among newly developing clones of memory cells, which differed from persisting clones in targeting more conserved regions of the RBD. Overall, more than 50% of the analysed neutralizing antibodies in the memory compartment after the third mRNA vaccine dose neutralized the Omicron variant. Thus, individuals receiving three doses of an mRNA vaccine have a diverse memory B cell repertoire that can respond rapidly and produce antibodies capable of clearing even diversified variants such as Omicron. These data help to explain why a third dose of a vaccine that was not specifically designed to protect against variants is effective against variant-induced serious disease., (© 2022. The Author(s).)

SARS-CoV-2 infection or vaccination produces neutralizing antibody responses that contribute to better clinical outcomes. The receptor-binding domain (RBD) and the N-terminal domain (NTD) of the spike trimer (S) constitute the two major neutralizing targets for antibodies. Here, we use NTD-specific probes to capture anti-NTD memory B cells in a longitudinal cohort of infected individuals, some of whom were vaccinated. We found 6 complementation groups of neutralizing antibodies. 58% targeted epitopes outside the NTD supersite, 58% neutralized either Gamma or Omicron, and 14% were broad neutralizers that also neutralized Omicron. Structural characterization revealed that broadly active antibodies targeted three epitopes outside the NTD supersite including a class that recognized both the NTD and SD2 domain. Rapid recruitment of memory B cells producing these antibodies into the plasma cell compartment upon re-infection likely contributes to the relatively benign course of subsequent infections with SARS-CoV-2 variants, including Omicron., Competing Interests: Declaration of interests The Rockefeller University has filed a provisional patent application in connection with this work on which M.C.N. and Z.W. are inventors (US patent 17/575,246)., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

HIV-1 infection remains a public health problem with no cure. Anti-retroviral therapy (ART) is effective but requires lifelong drug administration owing to a stable reservoir of latent proviruses integrated into the genome of CD4 + T cells 1 . Immunotherapy with anti-HIV-1 antibodies has the potential to suppress infection and increase the rate of clearance of infected cells 2,3 . Here we report on a clinical study in which people living with HIV received seven doses of a combination of two broadly neutralizing antibodies over 20 weeks in the presence or absence of ART. Without pre-screening for antibody sensitivity, 76% (13 out of 17) of the volunteers maintained virologic suppression for at least 20 weeks off ART. Post hoc sensitivity analyses were not predictive of the time to viral rebound. Individuals in whom virus remained suppressed for more than 20 weeks showed rebound viraemia after one of the antibodies reached serum concentrations below 10 µg ml -1 . Two of the individuals who received all seven antibody doses maintained suppression after one year. Reservoir analysis performed after six months of antibody therapy revealed changes in the size and composition of the intact proviral reservoir. By contrast, there was no measurable decrease in the defective reservoir in the same individuals. These data suggest that antibody administration affects the HIV-1 reservoir, but additional larger and longer studies will be required to define the precise effect of antibody immunotherapy on the reservoir., (© 2022. The Author(s).)

Antiretroviral therapy is highly effective in suppressing human immunodeficiency virus (HIV) 1 . However, eradication of the virus in individuals with HIV has not been possible to date 2 . Given that HIV suppression requires life-long antiretroviral therapy, predominantly on a daily basis, there is a need to develop clinically effective alternatives that use long-acting antiviral agents to inhibit viral replication 3 . Here we report the results of a two-component clinical trial involving the passive transfer of two HIV-specific broadly neutralizing monoclonal antibodies, 3BNC117 and 10-1074. The first component was a randomized, double-blind, placebo-controlled trial that enrolled participants who initiated antiretroviral therapy during the acute/early phase of HIV infection. The second component was an open-label single-arm trial that enrolled individuals with viraemic control who were naive to antiretroviral therapy. Up to 8 infusions of 3BNC117 and 10-1074, administered over a period of 24 weeks, were well tolerated without any serious adverse events related to the infusions. Compared with the placebo, the combination broadly neutralizing monoclonal antibodies maintained complete suppression of plasma viraemia (for up to 43 weeks) after analytical treatment interruption, provided that no antibody-resistant HIV was detected at the baseline in the study participants. Similarly, potent HIV suppression was seen in the antiretroviral-therapy-naive study participants with viraemia carrying sensitive virus at the baseline. Our data demonstrate that combination therapy with broadly neutralizing monoclonal antibodies can provide long-term virological suppression without antiretroviral therapy in individuals with HIV, and our experience offers guidance for future clinical trials involving next-generation antibodies with long half-lives., (© 2022. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

The emergence of severe acute respiratory syndrome coronavirus 2 variants that have greater transmissibility and resistance to neutralizing antibodies has increased the incidence of breakthrough infections. We show that breakthrough infection increases neutralizing antibody titers to varying degrees depending on the nature of the breakthrough variant and the number of vaccine doses previously administered. Omicron breakthrough infection resulted in neutralizing antibody titers that were the highest across all groups, particularly against Omicron., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Background: Antiretroviral therapy (ART) has led to dramatic improvements in survival for people living with HIV, but is unable to cure infection, or induce viral control off therapy. Designing intervention trials with novel agents with the potential to confer a period of HIV remission without ART remains a key scientific and community goal. We detail the rationale, design, and outcomes of a randomised, placebo-controlled trial of two HIV-specific long-acting broadly neutralising antibodies (bNAbs): 3BNC117-LS and 10-1074-LS, which target CD4 binding site and V3 loop respectively, on post-treatment viral control., Methods: RIO is a randomised, placebo-controlled, double-blinded prospective phase II study. Eligible individuals will have started ART within 3 months of primary HIV infection and have viral sequences that appear to be sensitive to both bNAbs. It will randomise 72 eligible participants 1:1 to the following arms via a two-stage design. In Stage 1, arm A participants are given dual long-acting (LS-variants) bNAbs infusions, followed by intensively monitored Analytical Treatment Interruption (ATI) (n = 36); in arm B, participants receive placebo infusions followed by ATI. The primary endpoint will be time to viral rebound within 36 weeks after ATI. Upon viral rebound, the participant and researcher are unblinded. Participants in arm A recommence ART and complete the study. Participants in arm B are invited to restart ART and enroll into Stage 2 where they will receive open-label LS bNAbs, followed by a second ATI 24 weeks after. Secondary and exploratory endpoints include adverse events, time to undetectable viraemia after restarting ART, immunological markers, HIV proviral DNA, serum bNAb concentrations in blood, bNAb resistance at viral rebound, and quality of life measures., Discussion: The two-stage design was determined in collaboration with community involvement. This design allows all participants the option to receive bNAbs. It also tests the hypothesis that bNAbs may drive sustained HIV control beyond the duration of detectable bNAb concentrations. Community representatives were involved at all stages. This included the two-stage design, discussion on the criteria to restart ART, frequency of monitoring visits off ART, and reducing the risk of onward transmission to HIV-negative partners. It also included responding to the challenges of COVID-19., Trial Registration: The protocol is registered on Clinical., Trials: gov and EudraCT and has approval from UK Ethics and MHRA., (© 2022. The Author(s).)

Background: The administration of broadly neutralising anti-HIV-1 antibodies before latency reversal could facilitate elimination of HIV-1-infected CD4 T cells. We tested this concept by combining the broadly neutralising antibody 3BNC117 in combination with the latency-reversing agent romidepsin in people with HIV-1 who were taking suppressive antiretroviral therapy (ART)., Methods: We did a randomised, open-label, phase 2A trial at three university hospital centres in Denmark, Germany, and the USA. Eligible participants were virologically suppressed adults aged 18-65 years who were infected with HIV-1 and on ART for at least 18 months, with plasma HIV-1 RNA concentrations of less than 50 copies per mL for at least 12 months, and a CD4 T-cell count of greater than 500 cells per μL. Participants were randomly assigned (1:1) to receive 3BNC117 plus romidepsin or romidepsin alone in two cycles. All participants received intravenous infusions of romidepsin (5 mg/m 2 given over 120 min) at weeks 0, 1, and 2 (treatment cycle 1) and weeks 8, 9, and 10 (treatment cycle 2). Those in the 3BNC117 plus romidepsin group received an intravenous infusion of 3BNC117 (30 mg/kg given over 60 min) 2 days before each treatment cycle. An analytic treatment interruption (ATI) of ART was done at week 24 in both groups. Our primary endpoint was time to viral rebound during analytic treatment interruption, which was assessed in all participants who completed both treatment cycles and ATI. We used a log-rank test to compare time to viral rebound during analytic treatment interruption between the two groups. This trial is registered with ClinicalTrials.gov, NCT02850016. It is closed to new participants, and all follow-up is complete., Findings: Between March 20, 2017, and Aug 14, 2018, 22 people were enrolled and randomly assigned, 11 to the 3BNC117 plus romidepsin group and 11 to the romidepsin group. 19 participants completed both treatment cycles and the ATI: 11 in the 3BNC117 plus romidepsin group and 8 in the romidepsin group. The median time to viral rebound during ATI was 18 days (IQR 14-28) in the 3BNC117 plus romidepsin group and 28 days (21-35) in the romidepsin group B (p=0·0016). Although this difference was significant, prolongation of time to viral rebound was not clinically meaningful in either group. All participants in both groups reported adverse events, but overall the combination of 3BNC117 and romidepsin was safe. Two severe adverse events were observed in the romidepsin group during 48 weeks of follow-up, one of which-increased direct bilirubin-was judged to be related to treatment., Interpretation: The combination of 3BNC117 and romidepsin was safe but did not delay viral rebound during analytic treatment interruptions in individuals on long-term ART. The results of our trial could serve as a benchmark for further optimisation of HIV-1 curative strategies among people with HIV-1 who are taking suppressive ART., Funding: amfAR, German Center for Infection Research., Competing Interests: Declaration of interests HG and FK are listed as inventors on a patent application for HIV-1 neutralising antibodies filed by the University of Cologne. MCN is listed as an inventor on patents for the antibody 3BNC117. All other authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Objectives: This study sought to determine the degree of Evolut (Medtronic) leaflet pinning, diameter expansion, leaflet overhang, and performance at different implant depths of the balloon-expandable Sapien 3 (S3, Edwards Lifesciences LLC) transcatheter heart valve (THV) within the Evolut THV., Background: Preservation of coronary access and flow is a major factor when considering the treatment of failed Evolut THVs., Methods: An in vitro study was performed with 20-, 23-, 26-, and 29-mm S3 THVs deployed within 23-, 26-, 29-, and 34-mm Evolut R THVs, respectively. The S3 outflow was positioned at various depths at node 4, 5, and 6 of the Evolut R. Neoskirt height, leaflet overhang, performance, and Evolut R valve housing diameter expansion were assessed under physiological conditions as per ISO 5840-3 standard., Results: The neoskirt height for the Evolut R was shorter when the S3 outflow was positioned at node 4 compared with node 6 (node 4 height for 23 mm = 16.3 mm, 26 mm = 17.1 mm, 29 mm = 18.3 mm, and 34 mm = 19.9 mm vs node 6 height for 23 mm = 23.9 mm, 26 mm = 23.4 mm, 29 mm = 24.7 mm, and 34 mm = 27 mm Evolut R). All configurations exhibited acceptable hydrodynamic performance irrespective of the degree of leaflet overhang, except the 29-mm S3 implanted in 34-mm Evolut R at node 4 (regurgitant fraction >20%). The valve housing radius of the index Evolut R increased when the S3 was implanted, with the increase ranging from 0 to 2.5 mm., Conclusions: Placement of the S3 at a lower implant position within an index Evolut R reduces the neoskirt height with no significant compromise to S3 valve function despite a higher degree of leaflet overhang. Low S3 implantation may facilitate future coronary access after redo transcatheter aortic valve replacement., Competing Interests: Funding Support and Author Disclosures Funding for the study was provided by Medtronic. Dr Akodad has received research funding from Medtronic, Biotronik, MUSE Explore, and Federation Française de Cardiologie. Dr Tang is a physician proctor and consultant for Medtronic; is a consultant for Abbott Structural Heart and NeoChord; and is a physician advisory board member for Abbott Structural Heart and JenValve. Dr Gada is a consultant for Abbott Vascular, Bard Medical, Boston Scientific, and Medtronic. Dr Rogers is a consultant and physician proctor to Edwards Lifesciences and Medtronic; has equity in Transmural Systems; and is a co-inventor on dedicated electrosurgery devices assigned to NIH. Dr Rutkin serves as a consultant for Medtronic. Dr Puri is a consultant to Medtronic, Boston Scientific, Philips, Bioventrix, Products & Features, Shockwave Medical, Centerline Biomedical, and VDyne. Dr Rovin is a physician proctor with Medtronic and Abbott; and is a Speakers Bureau for Medtronic and Abbott. Dr Leipsic holds institutional research core lab agreements with Medtronic, Edwards Lifesciences, Abbott, Boston Scientific, and Pi CARDIA. Dr Caskey serves as a proctor for Medtronic. Dr Sondergaard has received consultant fees and/or institutional research grants from Abbott, Boston Scientific, Edwards Lifesciences, Medtronic, and Sahajanand Medical Technology. Dr Grubb is a speaker, proctor, and principal investigator for Edwards Lifesciences; is a speaker, proctor, and principal investigator for Medtronic; and her employer receives institutional grants and educational funding from Edwards Lifesciences and Medtronic. Dr Gleason’s employer receives institutional grants and educational funding from Edwards Lifesciences and Medtronic; he has no personal financial disclosures. Ms Garde, Mr Tadros, and Mr Teodoru are all employees and shareholders of Medtronic. Dr Wood is a consultant and receives unrestricted grant support from Medtronic, Edwards Lifesciences, and Abbott Vascular. Mr Sathananthan is a consultant to Edwards Lifesciences and Medtronic; and has received speaking fees from Edwards Lifesciences and NVT. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)