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1.
Pathog Immun ; 9(1): 138-155, 2024.
Article in English | MEDLINE | ID: mdl-38746756

ABSTRACT

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

2.
J Infect Dis ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38716969

ABSTRACT

BACKGROUND: Monoclonal antibodies (mAbs) represent a crucial antiviral strategy for SARS-CoV-2 infection, but it is unclear whether combination mAbs offer a benefit over single-active mAb treatment. Amubarvimab and romlusevimab significantly reduced the risk of hospitalizations or death in the ACTIV-2/A5401 trial. Certain SARS-CoV-2 variants are intrinsically resistant against romlusevimab, leading to only single-active mAb therapy with amubarvimab in these variants. We evaluated virologic outcomes in individuals treated with single- versus dual-active mAbs. METHODS: Participants were non-hospitalized adults at higher risk of clinical progression randomized to amubarvimab plus romlusevimab or placebo. Quantitative SARS-CoV-2 RNA levels and targeted S gene next-generation sequencing was performed on anterior nasal samples. We compared viral load kinetics and resistance emergence between individuals treated with effective single- versus dual-active mAbs depending on the infecting variant. RESULTS: Study participants receiving single- and dual-active mAbs had similar demographics, baseline nasal viral load, symptom score, and symptom duration. Compared to single-active mAb, treatment with dual-active mAbs led to faster viral load decline at study day 3 (p < 0.001) and day 7 (p < 0.01). Treatment-emergent resistance mutations were more likely to be detected after amubarvimab plus romlusevimab treatment than placebo (2.6% vs 0%, P < 0.001), and more frequently detected in the setting of single-active compared to dual-active mAb treatment (7.2% vs 1.1%, p < 0.01). Single-active and dual-active mAb treatment resulted in similar decrease in rates of hospitalizations or death. CONCLUSION: Compared to single-active mAb therapy, dual-active mAbs led to similar clinical outcomes, but significantly faster viral load decline and a lower risk of emergent resistance.

3.
bioRxiv ; 2024 May 05.
Article in English | MEDLINE | ID: mdl-38746144

ABSTRACT

Most people living with HIV-1 experience rapid viral rebound once antiretroviral therapy is interrupted; however, a small fraction remain in viral remission for an extended duration. Understanding the factors that determine whether viral rebound is likely after treatment interruption can enable the development of optimal treatment regimens and therapeutic interventions to potentially achieve a functional cure for HIV-1. We built upon the theoretical framework proposed by Conway and Perelson to construct dynamic models of virus-immune interactions to study factors that influence viral rebound dynamics. We evaluated these models using viral load data from 24 individuals following antiretroviral therapy interruption. The best-performing model accurately captures the heterogeneity of viral dynamics and highlights the importance of the effector cell expansion rate. Our results show that post-treatment controllers and non-controllers can be distinguished based on the effector cell expansion rate in our models. Furthermore, these results demonstrate the potential of using dynamic models incorporating an effector cell response to understand early viral rebound dynamics post-antiretroviral therapy interruption.

5.
PLoS Pathog ; 20(4): e1011680, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38635853

ABSTRACT

To mitigate the loss of lives during the COVID-19 pandemic, emergency use authorization was given to several anti-SARS-CoV-2 monoclonal antibody (mAb) therapies for the treatment of mild-to-moderate COVID-19 in patients with a high risk of progressing to severe disease. Monoclonal antibodies used to treat SARS-CoV-2 target the spike protein of the virus and block its ability to enter and infect target cells. Monoclonal antibody therapy can thus accelerate the decline in viral load and lower hospitalization rates among high-risk patients with variants susceptible to mAb therapy. However, viral resistance has been observed, in some cases leading to a transient viral rebound that can be as large as 3-4 orders of magnitude. As mAbs represent a proven treatment choice for SARS-CoV-2 and other viral infections, evaluation of treatment-emergent mAb resistance can help uncover underlying pathobiology of SARS-CoV-2 infection and may also help in the development of the next generation of mAb therapies. Although resistance can be expected, the large rebounds observed are much more difficult to explain. We hypothesize replenishment of target cells is necessary to generate the high transient viral rebound. Thus, we formulated two models with different mechanisms for target cell replenishment (homeostatic proliferation and return from an innate immune response antiviral state) and fit them to data from persons with SARS-CoV-2 treated with a mAb. We showed that both models can explain the emergence of resistant virus associated with high transient viral rebounds. We found that variations in the target cell supply rate and adaptive immunity parameters have a strong impact on the magnitude or observability of the viral rebound associated with the emergence of resistant virus. Both variations in target cell supply rate and adaptive immunity parameters may explain why only some individuals develop observable transient resistant viral rebound. Our study highlights the conditions that can lead to resistance and subsequent viral rebound in mAb treatments during acute infection.


Subject(s)
Antibodies, Monoclonal , COVID-19 Drug Treatment , COVID-19 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , SARS-CoV-2/immunology , SARS-CoV-2/drug effects , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal/immunology , Spike Glycoprotein, Coronavirus/immunology , COVID-19/immunology , COVID-19/virology , Antibodies, Viral/immunology , Antibodies, Viral/therapeutic use , Drug Resistance, Viral/immunology , Viral Load/drug effects , Antiviral Agents/therapeutic use , Antiviral Agents/pharmacology , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/therapeutic use
6.
Surg Endosc ; 38(4): 2231-2239, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38498213

ABSTRACT

BACKGROUND: Biosynthetic meshes afford the cost advantages of being made from fully synthetic material, but are also biodegradable, making them a versatile option that can be used in both clean and contaminated cases. The aim of this study is to evaluate the safety profile and long-term outcomes of using GORE BIO-A (BIO-A) as an adjunct to abdominal wall reconstruction in all wound classes. METHODS: A retrospective review identified patients undergoing abdominal hernia repair using BIO-A from October 2008 to June 2018. The primary outcome was hernia recurrence rate. Only patients with at least 6-month follow-up were included when looking at recurrence rates. Secondary outcomes included 30-day morbidity categorized according to CDC Surgical Site Infection Criteria, return to operating/procedure room (RTOR), 30-day readmission, length of stay (LOS), and mortality. RESULTS: A total of 207 patients were identified, CDC Wound Classification breakdown was 127 (61.4%), 41 (19.8%), 14 (6.8%), and 25 (12.1%) for wound classes I, II, III, and IV, respectively. Median follow-up was 55.4 months (range 0.2-162.4). Overall recurrence rate was 17.4%. Contaminated cases experienced higher recurrence rates (28.8% versus 10.4%, p = 0.002) at a mean follow up of 46.9 and 60.8 months for contaminated and clean patients, respectively. Recurrent patients had higher BMI (32.4 versus 28.4 kg/m2, p = 0.0011), larger hernias (162.2 versus 106.7 cm2, p = 0.10), higher LOS (11.1 versus 5.6 days, p = 0.0051), and higher RTOR rates (16.7% versus 5.6%, p = 0.053). 51 (24.5%) patients experienced some morbidity, including 19 (9.2%) surgical site occurences, 7 (3.4%) superficial surgical site infections, 16 (7.7%) deep surgical site infections, and 1 (0.5%) organ space infection. CONCLUSION: This study affirms the use of biosynthetic mesh as a cost-effective alternative in all wound classifications, yielding good outcomes, limited long-term complications, and low recurrence. rates.


Subject(s)
Hernia, Ventral , Surgical Wound Infection , Humans , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology , Surgical Wound Infection/surgery , Treatment Outcome , Neoplasm Recurrence, Local/surgery , Hernia, Ventral/surgery , Hernia, Ventral/complications , Retrospective Studies , Surgical Wound Dehiscence , Herniorrhaphy/methods , Surgical Mesh/adverse effects , Recurrence
7.
Open Forum Infect Dis ; 11(3): ofad694, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38449916

ABSTRACT

Background: T cells in people with human immunodeficiency virus (HIV) demonstrate an exhausted phenotype, and HIV-specific CD4+ T cells expressing programmed cell death 1 (PD-1) are enriched for latent HIV, making antibody to PD-1 a potential strategy to target the latent reservoir. Methods: This was a phase 1/2, randomized (4:1), double-blind, placebo-controlled study in adults with suppressed HIV on antiretroviral therapy with CD4+ counts ≥350 cells/µL who received 2 infusions of cemiplimab versus placebo. The primary outcome was safety, defined as any grade 3 or higher adverse event (AE) or any immune-related AE (irAE). Changes in HIV-1-specific polyfunctional CD4+ and CD8+ T-cell responses were evaluated. Results: Five men were enrolled (median CD4+ count, 911 cells/µL; median age, 51 years); 2 received 1 dose of cemiplimab, 2 received 2 doses, and 1 received placebo. One participant had a probable irAE (thyroiditis, grade 2); another had a possible irAE (hepatitis, grade 3), both after a single low-dose (0.3 mg/kg) infusion. The Safety Monitoring Committee recommended no further enrollment or infusions. All 4 cemiplimab recipients were followed for 48 weeks. No other cemiplimab-related serious AEs, irAEs, or grade 3 or higher AEs occurred. One 2-dose recipient of cemiplimab had a 6.2-fold increase in polyfunctional, Gag-specific CD8+ T-cell frequency with supportive increases in plasma HIV RNA and decreases in total HIV DNA. Conclusions: One of 4 participants exhibited increased HIV-1-specific T-cell responses and transiently increased HIV-1 expression following 2 cemiplimab infusions. The occurrence of irAEs after a single, low dose may limit translating the promising therapeutic results of cemiplimab for cancer to immunotherapeutic and latency reversal strategies for HIV. Clinical Trials Registration. NCT03787095.

8.
J Infect Dis ; 229(3): 619-620, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38386686
9.
medRxiv ; 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38370801

ABSTRACT

Pregnancy is a risk factor for increased severity of SARS-CoV-2 and other respiratory infections. The mechanisms underlying this risk have not been well-established, partly due to a limited understanding of how pregnancy shapes immune responses. To gain insight into the role of pregnancy in modulating immune responses at steady state and upon perturbation, we collected peripheral blood mononuclear cells (PBMC), plasma, and stool from 226 women, including 152 pregnant individuals (n = 96 with SARS-CoV-2 infection and n = 56 healthy controls) and 74 non-pregnant women (n = 55 with SARS-CoV-2 and n = 19 healthy controls). We found that SARS-CoV-2 infection was associated with altered T cell responses in pregnant compared to non-pregnant women. Differences included a lower percentage of memory T cells, a distinct clonal expansion of CD4-expressing CD8 + T cells, and the enhanced expression of T cell exhaustion markers, such as programmed cell death-1 (PD-1) and T cell immunoglobulin and mucin domain-3 (Tim-3), in pregnant women. We identified additional evidence of immune dysfunction in severely and critically ill pregnant women, including a lack of expected elevation in regulatory T cell (Treg) levels, diminished interferon responses, and profound suppression of monocyte function. Consistent with earlier data, we found maternal obesity was also associated with altered immune responses to SARS-CoV-2 infection, including enhanced production of inflammatory cytokines by T cells. Certain gut bacterial species were altered in pregnancy and upon SARS-CoV-2 infection in pregnant individuals compared to non-pregnant women. Shifts in cytokine and chemokine levels were also identified in the sera of pregnant individuals, most notably a robust increase of interleukin-27 (IL-27), a cytokine known to drive T cell exhaustion, in the pregnant uninfected control group compared to all non-pregnant groups. IL-27 levels were also significantly higher in uninfected pregnant controls compared to pregnant SARS-CoV-2-infected individuals. Using two different preclinical mouse models of inflammation-induced fetal demise and respiratory influenza viral infection, we found that enhanced IL-27 protects developing fetuses from maternal inflammation but renders adult female mice vulnerable to viral infection. These combined findings from human and murine studies reveal nuanced pregnancy-associated immune responses, suggesting mechanisms underlying the increased susceptibility of pregnant individuals to viral respiratory infections.

10.
JCI Insight ; 9(3)2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38329130

ABSTRACT

BACKGROUNDIdentifying factors that predict the timing of HIV rebound after treatment interruption will be crucial for designing and evaluating interventions for HIV remission.METHODSWe performed a broad evaluation of viral and immune factors that predict viral rebound (AIDS Clinical Trials Group A5345). Participants initiated antiretroviral therapy (ART) during chronic (N = 33) or early (N = 12) HIV infection with ≥ 2 years of suppressive ART and restarted ART if they had 2 viral loads ≥ 1,000 copies/mL after treatment interruption.RESULTSCompared with chronic-treated participants, early-treated individuals had smaller and fewer transcriptionally active HIV reservoirs. A higher percentage of HIV Gag-specific CD8+ T cell cytotoxic response was associated with lower intact proviral DNA. Predictors of HIV rebound timing differed between early- versus chronic-treated participants, as the strongest reservoir predictor of time to HIV rebound was level of residual viremia in early-treated participants and intact DNA level in chronic-treated individuals. We also identified distinct sets of pre-treatment interruption viral, immune, and inflammatory markers that differentiated participants who had rapid versus slow rebound.CONCLUSIONThe results provide an in-depth overview of the complex interplay of viral, immunologic, and inflammatory predictors of viral rebound and demonstrate that the timing of ART initiation modifies the features of rapid and slow viral rebound.TRIAL REGISTRATIONClinicalTrials.gov NCT03001128FUNDINGNIH National Institute of Allergy and Infectious Diseases, Merck.


Subject(s)
HIV Infections , Humans , Proviruses/genetics , CD8-Positive T-Lymphocytes , Viral Load , DNA
11.
Sci Transl Med ; 16(731): eadk1599, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38266109

ABSTRACT

Despite vaccination and antiviral therapies, immunocompromised individuals are at risk for prolonged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but the immune defects that predispose an individual to persistent coronavirus disease 2019 (COVID-19) remain incompletely understood. In this study, we performed detailed viro-immunologic analyses of a prospective cohort of participants with COVID-19. The median times to nasal viral RNA and culture clearance in individuals with severe immunosuppression due to hematologic malignancy or transplant (S-HT) were 72 and 40 days, respectively, both of which were significantly longer than clearance rates in individuals with severe immunosuppression due to autoimmunity or B cell deficiency (S-A), individuals with nonsevere immunodeficiency, and nonimmunocompromised groups (P < 0.01). Participants who were severely immunocompromised had greater SARS-CoV-2 evolution and a higher risk of developing resistance against therapeutic monoclonal antibodies. Both S-HT and S-A participants had diminished SARS-CoV-2-specific humoral responses, whereas only the S-HT group had reduced T cell-mediated responses. This highlights the varied risk of persistent COVID-19 across distinct immunosuppressive conditions and suggests that suppression of both B and T cell responses results in the highest contributing risk of persistent infection.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Prospective Studies , Kinetics , Immunosuppression Therapy
12.
Ann Intern Med ; 176(12): 1577-1585, 2023 12.
Article in English | MEDLINE | ID: mdl-37956428

ABSTRACT

BACKGROUND: Data are conflicting regarding an association between treatment of acute COVID-19 with nirmatrelvir-ritonavir (N-R) and virologic rebound (VR). OBJECTIVE: To compare the frequency of VR in patients with and without N-R treatment for acute COVID-19. DESIGN: Observational cohort study. SETTING: Multicenter health care system in Boston, Massachusetts. PARTICIPANTS: Ambulatory adults with acute COVID-19 with and without use of N-R. INTERVENTION: Receipt of 5 days of N-R treatment versus no COVID-19 therapy. MEASUREMENTS: The primary outcome was VR, defined as either a positive SARS-CoV-2 viral culture result after a prior negative result or 2 consecutive viral loads above 4.0 log10 copies/mL that were also at least 1.0 log10 copies/mL higher than a prior viral load below 4.0 log10 copies/mL. RESULTS: Compared with untreated persons (n = 55), those taking N-R (n = 72) were older, received more COVID-19 vaccinations, and more commonly had immunosuppression. Fifteen participants (20.8%) taking N-R had VR versus 1 (1.8%) who was untreated (absolute difference, 19.0 percentage points [95% CI, 9.0 to 29.0 percentage points]; P = 0.001). All persons with VR had a positive viral culture result after a prior negative result. In multivariable models, only N-R use was associated with VR (adjusted odds ratio, 10.02 [CI, 1.13 to 88.74]; P = 0.038). Virologic rebound was more common among those who started therapy within 2 days of symptom onset (26.3%) than among those who started 2 or more days after symptom onset (0%) (P = 0.030). Among participants receiving N-R, those who had VR had prolonged shedding of replication-competent virus compared with those who did not have VR (median, 14 vs. 3 days). Eight of 16 participants (50% [CI, 25% to 75%]) with VR also reported symptom rebound; 2 were completely asymptomatic. No post-VR resistance mutations were detected. LIMITATIONS: Observational study design with differences between the treated and untreated groups; positive viral culture result was used as a surrogate marker for risk for ongoing viral transmission. CONCLUSION: Virologic rebound occurred in approximately 1 in 5 people taking N-R, often without symptom rebound, and was associated with shedding of replication-competent virus. PRIMARY FUNDING SOURCE: National Institutes of Health.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Humans , Ritonavir/therapeutic use , COVID-19 Drug Treatment
13.
Nat Med ; 29(12): 3212-3223, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37957382

ABSTRACT

Non-suppressible HIV-1 viremia (NSV) is defined as persistent low-level viremia on antiretroviral therapy (ART) without evidence of ART non-adherence or significant drug resistance. Unraveling the mechanisms behind NSV would broaden our understanding of HIV-1 persistence. Here we analyzed plasma virus sequences in eight ART-treated individuals with NSV (88% male) and show that they are composed of large clones without evidence of viral evolution over time in those with longitudinal samples. We defined proviruses that match plasma HIV-1 RNA sequences as 'producer proviruses', and those that did not as 'non-producer proviruses'. Non-suppressible viremia arose from expanded clones of producer proviruses that were significantly larger than the genome-intact proviral reservoir of ART-suppressed individuals. Integration sites of producer proviruses were enriched in proximity to the activating H3K36me3 epigenetic mark. CD4+ T cells from participants with NSV demonstrated upregulation of anti-apoptotic genes and downregulation of pro-apoptotic and type I/II interferon-related pathways. Furthermore, participants with NSV showed significantly lower HIV-specific CD8+ T cell responses compared with untreated viremic controllers with similar viral loads. We identified potential critical host and viral mediators of NSV that may represent targets to disrupt HIV-1 persistence.


Subject(s)
HIV Infections , HIV Seropositivity , HIV-1 , Humans , Male , Female , HIV-1/genetics , Viremia , Proviruses/genetics , Proviruses/metabolism , HIV Infections/drug therapy , CD4-Positive T-Lymphocytes , RNA, Viral , Viral Load
14.
Sci Rep ; 13(1): 17898, 2023 10 19.
Article in English | MEDLINE | ID: mdl-37857680

ABSTRACT

Smoking negatively affects B cell function and immunoglobulin levels, but it is unclear if this immune dysfunction contributes to the risk of severe COVID-19 in smokers. We evaluated binding IgM, IgA and IgG antibodies to spike and receptor binding domain antigens, and used a pseudovirus assay to quantify neutralization titers in a set of 27 patients with severe COVID-19. We found no significant differences between binding and neutralization antibody responses for people with a smoking history and people who never smoked. High plasma viral load, but not antibody titers, was linked to an increased risk of death. Humoral immune dysfunction was not a major driver of severe COVID-19 in smokers.


Subject(s)
COVID-19 , Humans , SARS-CoV-2 , Smokers , Antibodies, Viral , Antibody Formation , Antibodies, Neutralizing , Immunoglobulin M
15.
EClinicalMedicine ; 65: 102250, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37855026

ABSTRACT

Background: With the emergence of SARS-CoV-2 variants resistant to monoclonal antibody therapies and limited global access to therapeutics, the evaluation of novel therapeutics to prevent progression to severe COVID-19 remains a critical need. Methods: Safety, clinical and antiviral efficacy of inhaled interferon-ß1a (SNG001) were evaluated in a phase II randomized controlled trial on the ACTIV-2/A5401 platform (ClinicalTrials.govNCT04518410). Adult outpatients with confirmed SARS-CoV-2 infection within 10 days of symptom onset were randomized and initiated either orally inhaled nebulized SNG001 given once daily for 14 days (n = 110) or blinded pooled placebo (n = 110) between February 10 and August 18, 2021. Findings: The proportion of participants reporting premature treatment discontinuation was 9% among SNG001 and 13% among placebo participants. There were no differences between participants who received SNG001 or placebo in the primary outcomes of treatment emergent Grade 3 or higher adverse events (3.6% and 8.2%, respectively), time to symptom improvement (median 13 and 9 days, respectively), or proportion with unquantifiable nasopharyngeal SARS-CoV-2 RNA at days 3 (28% [26/93] vs. 39% [37/94], respectively), 7 (65% [60/93] vs. 66% [62/94]) and 14 (91% [86/95] vs. 91% [83/81]). There were fewer hospitalizations with SNG001 (n = 1; 1%) compared with placebo (n = 7; 6%), representing an 86% relative risk reduction (p = 0.07). There were no deaths in either arm. Interpretation: In this trial, SNG001 was safe and associated with a non-statistically significant decrease in hospitalization for COVID-19 pneumonia. Funding: The ACTIV-2 platform study is funded by the NIH. Research reported in this publication was supported by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health under Award Number UM1 AI068634, UM1 AI068636 and UM1 AI106701. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

16.
bioRxiv ; 2023 Sep 17.
Article in English | MEDLINE | ID: mdl-37745410

ABSTRACT

The COVID-19 pandemic has led to over 760 million cases and 6.9 million deaths worldwide. To mitigate the loss of lives, emergency use authorization was given to several anti-SARS-CoV-2 monoclonal antibody (mAb) therapies for the treatment of mild-to-moderate COVID-19 in patients with a high risk of progressing to severe disease. Monoclonal antibodies used to treat SARS-CoV-2 target the spike protein of the virus and block its ability to enter and infect target cells. Monoclonal antibody therapy can thus accelerate the decline in viral load and lower hospitalization rates among high-risk patients with susceptible variants. However, viral resistance has been observed, in some cases leading to a transient viral rebound that can be as large as 3-4 orders of magnitude. As mAbs represent a proven treatment choice for SARS-CoV-2 and other viral infections, evaluation of treatment-emergent mAb resistance can help uncover underlying pathobiology of SARS-CoV-2 infection and may also help in the development of the next generation of mAb therapies. Although resistance can be expected, the large rebounds observed are much more difficult to explain. We hypothesize replenishment of target cells is necessary to generate the high transient viral rebound. Thus, we formulated two models with different mechanisms for target cell replenishment (homeostatic proliferation and return from an innate immune response anti-viral state) and fit them to data from persons with SARS-CoV-2 treated with a mAb. We showed that both models can explain the emergence of resistant virus associated with high transient viral rebounds. We found that variations in the target cell supply rate and adaptive immunity parameters have a strong impact on the magnitude or observability of the viral rebound associated with the emergence of resistant virus. Both variations in target cell supply rate and adaptive immunity parameters may explain why only some individuals develop observable transient resistant viral rebound. Our study highlights the conditions that can lead to resistance and subsequent viral rebound in mAb treatments during acute infection.

17.
Am J Respir Crit Care Med ; 208(12): 1293-1304, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37774011

ABSTRACT

Rationale: The effects of high-dose inhaled nitric oxide on hypoxemia in coronavirus disease (COVID-19) acute respiratory failure are unknown. Objectives: The primary outcome was the change in arterial oxygenation (PaO2/FiO2) at 48 hours. The secondary outcomes included: time to reach a PaO2/FiO2.300mmHg for at least 24 hours, the proportion of participants with a PaO2/FiO2.300mmHg at 28 days, and survival at 28 and at 90 days. Methods: Mechanically ventilated adults with COVID-19 pneumonia were enrolled in a phase II, multicenter, single-blind, randomized controlled parallel-arm trial. Participants in the intervention arm received inhaled nitric oxide at 80 ppm for 48 hours, compared with the control group receiving usual care (without placebo). Measurements and Main Results: A total of 193 participants were included in the modified intention-to-treat analysis. The mean change in PaO2/FiO2 ratio at 48 hours was 28.3mmHg in the intervention group and 21.4mmHg in the control group (mean difference, 39.1mmHg; 95% credible interval [CrI], 18.1 to 60.3). The mean time to reach a PaO2/FiO2.300mmHg in the interventional group was 8.7 days, compared with 8.4 days for the control group (mean difference, 0.44; 95% CrI, 23.63 to 4.53). At 28 days, the proportion of participants attaining a PaO2/FiO2.300mmHg was 27.7% in the inhaled nitric oxide group and 17.2% in the control subjects (risk ratio, 2.03; 95% CrI, 1.11 to 3.86). Duration of ventilation and mortality at 28 and 90 days did not differ. No serious adverse events were reported. Conclusions: The use of high-dose inhaled nitric oxide resulted in an improvement of PaO2/FiO2 at 48 hours compared with usual care in adults with acute hypoxemic respiratory failure due to COVID-19.


Subject(s)
COVID-19 , Respiratory Insufficiency , Adult , Humans , Nitric Oxide/therapeutic use , COVID-19/complications , Single-Blind Method , Respiratory Insufficiency/drug therapy , Respiratory Insufficiency/etiology , Respiration, Artificial , Administration, Inhalation
18.
J Acquir Immune Defic Syndr ; 94(2S): S116-S121, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37707858

ABSTRACT

BACKGROUND: The underrepresentation of historically marginalized groups in the HIV research workforce is a barrier to reaching national Ending the Epidemic goals. SETTING: The Harvard University Center for AIDS Research (HU CFAR) Diversity Equity and Inclusion Working Group (DEI WG) uses a multifaceted approach to enhance the field's diversity. METHODS: We established a DEI WG to improve the recruitment, inclusion, and retention of underrepresented minorities (URMs) in HIV research. We use community-based, participatory processes to establish and expand education and outreach programs about HIV care and research to better connect the HU CFAR to communities affected by HIV. This article reports on the development of the WG in July 2022, progress in its first year, and future plans. RESULTS: We have built a network of >50 investigators across the university for monthly meetings; partnered with existing research pathway programs for high school, undergraduate, and graduate students, directly supporting 7 new trainees and linking CFAR investigators to additional mentorship opportunities; and created 2-year Scholar Awards for 5 URM investigators in HIV. Planned work includes needs assessments for early-stage investigators to understand factors contributing to inclusion and retention and new pathway and outreach programming being developed with community partner minority-serving institutions. CONCLUSIONS: The HU CFAR DEI WG strives to ensure that individuals from underrepresented, marginalized, and minoritized communities have an opportunity to contribute to HIV research and that research is informed by the needs of the communities affected by the epidemic. An intersectional approach should be incorporated into HIV research pathway initiatives.


Subject(s)
Acquired Immunodeficiency Syndrome , Awards and Prizes , HIV Infections , Humans , HIV Infections/epidemiology , HIV Infections/prevention & control , Schools , Educational Status
19.
mBio ; 14(4): e0090223, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37535402

ABSTRACT

While immune correlates against SARS-CoV-2 are typically defined at peak immunogenicity following vaccination, immunologic responses that expand selectively during the anamnestic response following infection can provide mechanistic and detailed insights into the immune mechanisms of protection. Moreover, whether anamnestic correlates are conserved across variants of concern (VOC), including the Delta and more distant Omicron VOC, remains unclear. To define the anamnestic correlates of immunity, across VOCs, we deeply profiled the humoral immune response in individuals infected with sequence-confirmed Delta or Omicron VOC after completing the vaccination series. While limited acute N-terminal domain and receptor-binding domain (RBD)-specific immune expansion was observed following breakthrough infection, a significant immunodominant expansion of opsonophagocytic Spike-specific antibody responses focused largely on the conserved S2-domain of SARS-CoV-2 was observed. This S2-specific functional humoral response continued to evolve over 2-3 weeks following Delta or Omicron breakthrough, targeting multiple VOCs and common coronaviruses. Strong responses were observed on the fusion peptide (FP) region and the heptad repeat 1 (HR1) region adjacent to the RBD. Notably, the FP is highly conserved across SARS-related coronaviruses and even non-SARS-related betacoronavirus. Taken together, our results point to a critical role of highly conserved, functional S2-specific responses in the anamnestic antibody response to SARS-CoV-2 infection across VOCs. These humoral responses linked to virus clearance can guide next-generation vaccine-boosting approaches to confer broad protection against future SARS-related coronaviruses. IMPORTANCE The Spike protein of SARS-CoV-2 is the primary target of antibody-based recognition. Selective pressures, be it the adaption to human-to-human transmission or evasion of previously acquired immunity, have spurred the emergence of variants of the virus such as the Delta and Omicron lineages. Therefore, understanding how antibody responses are expanded in breakthrough cases of previously vaccinated individuals can provide insights into key correlates of protection against current and future variants. Here, we show that vaccinated individuals who had documented COVID-19 breakthrough showed anamnestic antibody expansions targeting the conserved S2 subdomain of Spike, particularly within the fusion peptide region. These S2-directed antibodies were highly leveraged for non-neutralizing, phagocytic functions and were similarly expanded independent of the variant. We propose that through deep profiling of anamnestic antibody responses in breakthrough cases, we can identify antigen targets susceptible to novel monoclonal antibody therapy or vaccination-boosting strategies.


Subject(s)
COVID-19 , Humans , SARS-CoV-2/genetics , Antibodies , Antibodies, Viral , Antibodies, Neutralizing
20.
medRxiv ; 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37577493

ABSTRACT

Despite vaccination and antiviral therapies, immunocompromised individuals are at risk for prolonged SARS-CoV-2 infection, but the immune defects that predispose to persistent COVID-19 remain incompletely understood. In this study, we performed detailed viro-immunologic analyses of a prospective cohort of participants with COVID-19. The median time to nasal viral RNA and culture clearance in the severe hematologic malignancy/transplant group (S-HT) were 72 and 40 days, respectively, which were significantly longer than clearance rates in the severe autoimmune/B-cell deficient (S-A), non-severe, and non-immunocompromised groups (P<0.001). Participants who were severely immunocompromised had greater SARS-CoV-2 evolution and a higher risk of developing antiviral treatment resistance. Both S-HT and S-A participants had diminished SARS-CoV-2-specific humoral, while only the S-HT group had reduced T cell-mediated responses. This highlights the varied risk of persistent COVID-19 across immunosuppressive conditions and suggests that suppression of both B and T cell responses results in the highest contributing risk of persistent infection.

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