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1.
Glob Adv Integr Med Health ; 13: 27536130241285029, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39280090

RESUMO

Background: Cancer remains a leading chronic disease in the United States with a high burden of disease and challenging treatment protocol. Nutrition is critically linked to long-term health outcomes and recovery rates among cancer patients, but there remains a persistent gap in clinician training regarding functional nutrition. This study interviews patients to understand their experiences of nutrition support they received while in cancer treatment. Objectives: Understand patient experiences and needs regarding cancer treatment (i.e., surgery, chemotherapy, radiation, and/or immunotherapy) and available nutrition counseling. Methods: This was a multi-phase study incorporating survey data (n = 50) and follow-up, semi-structured interviews (n = 20) of cancer patients in the Mid-Atlantic United States. Interview participants included those undergoing active cancer treatment (n = 7) and those in remission at the time of contact (n = 13). Participants shared their experiences receiving treatment and their perspectives regarding the quality of care they received in outpatient oncology clinics. Central to this study was a discussion regarding the quality of nutrition counseling they received while in treatment. Results: Five themes emerged through data collection and analysis: (1) patients need additional education regarding nutrition, (2) personalized resources are not readily available, (3) perceptions from patients that oncologists receive little formal nutrition training related to cancer, (4) oncologists' attitude toward nutrition may influence patient care, and (5) patients seek nutrition information through informal sources. Commonly, patients had little access to licensed dieticians or other professionals capable of providing lifestyle recommendations. Conclusions: The results of this study are being used to develop a clinician toolbox of resources, recommendations, and services that can be shared with patients seeking additional information regarding nutrition and diet change.

2.
bioRxiv ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39071307

RESUMO

Adaptive immunity is critical to eliminate malignant cells, while multiple tumor-intrinsic factors can alter this protective function. Melanoma antigen-A4 (MAGE-A4), a cancer-testis antigen, is expressed in several solid tumors and correlates with poor survival in non-small cell lung cancer (NSCLC), but its role in altering antitumor immunity remains unclear. We found that expression of MAGE-A4 was highly associated with the loss of PTEN , a tumor suppressor, in human NSCLC. Here we show that constitutive expression of human MAGE-A4 combined with the loss of Pten in mouse airway epithelial cells results in metastatic adenocarcinoma enriched in CD138 + CXCR4 + plasma cells, predominantly expressing IgA. Consistently, human NSCLC expressing MAGE-A4 showed increased CD138 + IgA + plasma cell density surrounding tumors. The abrogation of MAGE-A4-responsive plasma cells (MARPs) decreased tumor burden, increased T cell infiltration and activation, and reduced CD163 + CD206 + macrophages in mouse lungs. These findings suggest MAGE-A4 promotes NSCLC tumorigenesis, in part, through the recruitment and retention of IgA + MARPs in the lungs.

3.
Sci Immunol ; 8(86): eadg0539, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37624909

RESUMO

PD-1+TCF-1+ stem-like CD8 T cells act as critical resource cells for maintaining T cell immunity in chronic viral infections and cancer. In addition, they provide the proliferative burst of effector CD8 T cells after programmed death protein 1 (PD-1)-directed immunotherapy. However, it is not known whether checkpoint blockade diminishes the number of these stem-like progenitor cells as effector cell differentiation increases. To investigate this, we used the mouse model of chronic lymphocytic choriomeningitis virus (LCMV) infection. Treatment of chronically infected mice with either αPD-1 or αPD-L1 antibody not only increased effector cell differentiation from the virus-specific stem-like CD8 T cells but also increased their proliferation so their numbers were maintained. The increased self-renewal of LCMV-specific stem-like CD8 T cells was mTOR dependent. We used microscopy to understand the division of these progenitor cells and found that after PD-1 blockade, an individual dividing cell could give rise to a differentiated TCF-1- daughter cell alongside a self-renewing TCF-1+ sister cell. This asymmetric division helped to preserve the number of stem-like cells. Moreover, we found that the PD-1+TCF-1+ stem-like CD8 T cells retained their transcriptional program and their in vivo functionality in terms of responding to viral infection and to repeat PD-1 blockade. Together, our results demonstrate that PD-1 blockade does not deplete the stem-like population despite increasing effector differentiation. These findings have implications for PD-1-directed immunotherapy in humans.


Assuntos
Linfócitos T CD8-Positivos , Receptor de Morte Celular Programada 1 , Humanos , Animais , Camundongos , Anticorpos , Diferenciação Celular , Modelos Animais de Doenças
4.
J Opt Soc Am A Opt Image Sci Vis ; 40(5): 942-954, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37133191

RESUMO

Medical imaging devices are becoming increasingly compact, necessitating optimization research into different methods of actuation. Actuation influences important parameters of the imaging device such as size, weight, frame rate, field of view (FOV), and image reconstruction for imaging devices point scanning techniques. Current literature around piezoelectric fiber cantilever actuators focuses on device optimization with a fixed FOV but neglects adjustability. In this paper, we introduce an adjustable FOV piezoelectric fiber cantilever microscope and provide a characterization and optimization procedure. To overcome calibration challenges, we utilize a position sensitive detector (PSD) and address trade-offs between FOV and sparsity with a novel inpainting technique. Our work demonstrates the potential for scanner operation when sparsity and distortion dominate the FOV, extending the usable FOV for this form of actuation and others that currently only operate under ideal imaging conditions.

5.
Cell Rep Med ; 4(6): 101054, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209684

RESUMO

Radiation is commonly used in the treatment of many cancers. However, its effects on anti-tumor immune responses are incompletely understood. Here, we present a detailed immunological analysis of two tumors from a patient with multiple non-small cell lung cancer metastases to the brain. One tumor was resected without treatment; the second was irradiated to a total dose of 30 Gy and resected following further progression. Comprehensive single-cell analysis reveals a substantially reduced immune cell fraction in the irradiated tumor, including the depletion of tissue-resident macrophages and infiltration of pro-inflammatory monocytes. Despite the presence of similar somatic mutations in both tumors, radiation is associated with the depletion of exhausted, tumor-resident T cell clones and their replacement by circulating clones unlikely to contribute to tumor-specific immunity. These results provide insight into the local effects of radiation on anti-tumor immunity and raise important considerations for the combination of radiation and immunotherapy.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Encefálicas/radioterapia , Encéfalo/patologia , Linfócitos T/patologia , Microambiente Tumoral
6.
J Clin Invest ; 133(2)2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36378537

RESUMO

T cell exhaustion is a state of T cell dysfunction associated with expression of programmed death 1 (PD-1). Exhausted CD8+ T cells are maintained by self-renewing stem-like T cells that provide differentiated TIM3+ cells, a part of which possesses effector-like properties. PD-1-targeted therapies enhance T cell response by promoting differentiation of stem-like T cells toward TIM3+ cells, but the role of mTOR during T cell exhaustion remains elusive. Here, we showed that mTOR inhibition has distinct outcomes during the beginning of and after the establishment of chronic viral infection. Blocking mTOR during the T cell expansion phase enhanced the T cell response by causing accumulation of stem-like T cells, leading to improved efficacy of PD-1 immunotherapy; whereas, after exhaustion progressed, mTOR inhibition caused immunosuppression, characterized by decreased TIM3+ cells and increased viral load with minimal changes in stem-like T cells. Mechanistically, a cell-intrinsic mTOR signal was vital for differentiation of stem-like T cells into the TIM3+ state in the early and late phases of chronic infection as well as during PD-1 immunotherapy. Thus, PD-1 blockade worked after cessation of mTOR inhibition, but simultaneous treatment failed to induce functional TIM3+ cells, reducing efficacy of PD-1 immunotherapy. Our data demonstrate that mTOR regulates T cell exhaustion and have important implications for combination cancer therapies with PD-1 blockade.


Assuntos
Receptor de Morte Celular Programada 1 , Viroses , Linfócitos T CD8-Positivos/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Imunoterapia , Infecção Persistente , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Exaustão das Células T , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Viroses/metabolismo
7.
Cancer Cell ; 41(1): 41-57, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36206755

RESUMO

T cells are at the center of cancer immunology because of their ability to recognize mutations in tumor cells and directly mediate cancer cell killing. Immunotherapies to rejuvenate exhausted T cell responses have transformed the clinical management of several malignancies. In parallel, the development of novel multidimensional analysis platforms, such as single-cell RNA sequencing and high-dimensional flow cytometry, has yielded unprecedented insights into immune cell biology. This convergence has revealed substantial heterogeneity of tumor-infiltrating immune cells in single tumors, across tumor types, and among individuals with cancer. Here we discuss the opportunities and challenges of studying the complex tumor microenvironment with -omics technologies that generate vast amounts of data, highlighting the opportunities and limitations of these technologies with a particular focus on interpreting high-dimensional studies of CD8+ T cells in the tumor microenvironment.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Imunoterapia , Linfócitos do Interstício Tumoral , Microambiente Tumoral
8.
J Virol ; 97(1): e0155622, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36541799

RESUMO

Increased demand for novel, highly effective vaccination strategies necessitates a better understanding of long-lived memory CD8 T cell differentiation. To achieve this understanding, we used the mouse model of acute lymphocytic choriomeningitis virus (LCMV) infection. We reexamined classical memory CD8 T cell subsets and performed in-depth, longitudinal analysis of their phenotype, transcriptional programming, and anatomic location within the spleen. All analyses were performed at multiple time points from 8 days to 1 year postinfection. Memory subsets are conventionally defined by their expression of KLRG1 and IL-7Rα, as follows: KLRG1+IL-7Rα- terminal effectors (TEs) and KLRG1-IL-7Rα+ memory precursors (MPs). But we also characterized a third KLRG1+IL-7Rα+ subset which we refer to as KLRG1+ MPs. In these analyses, we defined a comprehensive memory phenotype that is associated with higher levels of CD28 expression. We also demonstrated that MPs, KLRG1+ MPs, and TEs have distinct localization programs within the spleen. We found that MPs became preferentially enriched in the white pulp as early as 1 to 2 weeks postinfection, and their predominance in the white pulp was maintained throughout the course of a year. On the other hand, KLRG1+ MPs and TEs localized to the red pulp just as early, and they consistently localized to the red pulp thereafter. These findings indicate that location may be crucial for memory formation and that white pulp-derived signals may contribute to long-term memory survival. Achieving robust memory responses following vaccination may require more deliberate consideration of which memory phenotypes are induced, as well as where they traffic, as these factors could impact their longevity. IMPORTANCE CD8 T cells play a critical role in viral immunity and it is important to understand how memory cells are formed and what processes lead to their long-term maintenance. Here, we use a mouse model of acute infection to perform an in-depth, longitudinal analysis of memory CD8 T cell differentiation, examining the phenotype and location of memory cells out to 1 year postinfection.


Assuntos
Coriomeningite Linfocítica , Subpopulações de Linfócitos T , Animais , Camundongos , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica , Camundongos Endogâmicos C57BL , Fenótipo , Vacinação , Antígenos CD28/genética , Transcriptoma , Antígenos de Superfície/genética , Vacinas Virais/imunologia
9.
Cell ; 185(19): 3603-3616.e13, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36084631

RESUMO

The effects of mutations in continuously emerging variants of SARS-CoV-2 are a major concern for the performance of rapid antigen tests. To evaluate the impact of mutations on 17 antibodies used in 11 commercially available antigen tests with emergency use authorization, we measured antibody binding for all possible Nucleocapsid point mutations using a mammalian surface-display platform and deep mutational scanning. The results provide a complete map of the antibodies' epitopes and their susceptibility to mutational escape. Our data predict no vulnerabilities for detection of mutations found in variants of concern. We confirm this using the commercial tests and sequence-confirmed COVID-19 patient samples. The antibody escape mutational profiles generated here serve as a valuable resource for predicting the performance of rapid antigen tests against past, current, as well as any possible future variants of SARS-CoV-2, establishing the direct clinical and public health utility of our system.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos/genética , Humanos , Mamíferos , Mutação , Nucleocapsídeo , SARS-CoV-2/genética
10.
Nature ; 610(7930): 173-181, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36171288

RESUMO

Combination therapy with PD-1 blockade and IL-2 is highly effective during chronic lymphocytic choriomeningitis virus infection1. Here we examine the underlying basis for this synergy. We show that PD-1 + IL-2 combination therapy, in contrast to PD-1 monotherapy, substantially changes the differentiation program of the PD-1+TCF1+ stem-like CD8+ T cells and results in the generation of transcriptionally and epigenetically distinct effector CD8+ T cells that resemble highly functional effector CD8+ T cells seen after an acute viral infection. The generation of these qualitatively superior CD8+ T cells that mediate viral control underlies the synergy between PD-1 and IL-2. Our results show that the PD-1+TCF1+ stem-like CD8+ T cells, also referred to as precursors of exhausted CD8+ T cells, are not fate-locked into the exhaustion program and their differentiation trajectory can be changed by IL-2 signals. These virus-specific effector CD8+ T cells emerging from the stem-like CD8+ T cells after combination therapy expressed increased levels of the high-affinity IL-2 trimeric (CD25-CD122-CD132) receptor. This was not seen after PD-1 blockade alone. Finally, we show that CD25 engagement with IL-2 has an important role in the observed synergy between IL-2 cytokine and PD-1 blockade. Either blocking CD25 with an antibody or using a mutated version of IL-2 that does not bind to CD25 but still binds to CD122 and CD132 almost completely abrogated the synergistic effects observed after PD-1 + IL-2 combination therapy. There is considerable interest in PD-1 + IL-2 combination therapy for patients with cancer2,3, and our fundamental studies defining the underlying mechanisms of how IL-2 synergizes with PD-1 blockade should inform these human translational studies.


Assuntos
Linfócitos T CD8-Positivos , Interleucina-2 , Receptor de Morte Celular Programada 1 , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Subunidade gama Comum de Receptores de Interleucina , Interleucina-2/imunologia , Interleucina-2/farmacologia , Interleucina-2/uso terapêutico , Subunidade alfa de Receptor de Interleucina-2 , Subunidade beta de Receptor de Interleucina-2 , Coriomeningite Linfocítica/tratamento farmacológico , Coriomeningite Linfocítica/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Fator 1 de Transcrição de Linfócitos T
11.
J Exp Med ; 219(10)2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-35980386

RESUMO

Recent studies have defined a novel population of PD-1+ TCF-1+ stem-like CD8 T cells in chronic infections and cancer. These quiescent cells reside in lymphoid tissues, are critical for maintaining the CD8 T cell response under conditions of persistent antigen, and provide the proliferative burst after PD-1 blockade. Here we examined the role of TGF-ß in regulating the differentiation of virus-specific CD8 T cells during chronic LCMV infection of mice. We found that TGF-ß signaling was not essential for the generation of the stem-like CD8 T cells but was critical for maintaining the stem-like state and quiescence of these cells. TGF-ß regulated the unique transcriptional program of the stem-like subset, including upregulation of inhibitory receptors specifically expressed on these cells. TGF-ß also promoted the terminal differentiation of exhausted CD8 T cells by suppressing the effector-associated program. Together, the absence of TGF-ß signaling resulted in significantly increased accumulation of effector-like CD8 T cells. These findings have implications for immunotherapies in general and especially for T cell therapy against chronic infections and cancer.


Assuntos
Coriomeningite Linfocítica , Neoplasias , Animais , Linfócitos T CD8-Positivos , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos , Infecção Persistente , Receptor de Morte Celular Programada 1 , Fator de Crescimento Transformador beta
12.
STAR Protoc ; 3(2): 101391, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35707680

RESUMO

We present a protocol to localize T cell receptor clones using the Visium spatial transcriptomics platform. This approach permits simultaneous localization of both gene expression and T cell clonotypes in situ within tissue sections. T cell receptor sequences identified by this protocol are readily recapitulated by single-cell sequencing. This technique enables detailed studies of the spatial organization of the human T cell repertoire, such as the localization of infiltrating T cell clones within the tumor microenvironment. For complete details on the use and execution of this protocol, please refer to Sudmeier et al. (2022).


Assuntos
Linfócitos T , Transcriptoma , Células Clonais , Humanos , Transcriptoma/genética
13.
Cell Rep Med ; 3(5): 100620, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35584630

RESUMO

Metastatic disease in the brain is difficult to control and predicts poor prognosis. Here, we analyze human brain metastases and demonstrate their robust infiltration by CD8+ T cell subsets with distinct antigen specificities, phenotypic states, and spatial localization within the tumor microenvironment. Brain metastases are densely infiltrated by T cells; the majority of infiltrating CD8+ T cells express PD-1. Single-cell RNA sequencing shows significant clonal overlap between proliferating and exhausted CD8+ T cells, but these subsets have minimal clonal overlap with circulating and other tumor-infiltrating CD8+ T cells, including bystander CD8+ T cells specific for microbial antigens. Using spatial transcriptomics and spatial T cell receptor (TCR) sequencing, we show these clonally unrelated, phenotypically distinct CD8+ T cell populations occupy discrete niches within the brain metastasis tumor microenvironment. Together, our work identifies signaling pathways within CD8+ T cells and in their surrounding environment that may be targeted for immunotherapy of brain metastases.


Assuntos
Neoplasias Encefálicas , Linfócitos T CD8-Positivos , Neoplasias Encefálicas/metabolismo , Humanos , Receptores de Antígenos de Linfócitos T/genética , Subpopulações de Linfócitos T , Microambiente Tumoral
14.
Artigo em Inglês | MEDLINE | ID: mdl-34001528

RESUMO

Not simply an attribute of the adaptive immune system, immunological memory can be viewed on multiple levels. Accordingly, the molecular basis of memory comprises multiple mechanisms. The advent of new sequencing technologies has greatly enhanced the understanding of gene regulation and lymphocyte specification, and improved measurement of chromatin states affords new insights into the epigenomic and transcriptomic programs that underlie memory. Beyond canonical genes, the involvement of long noncoding RNAs (lncRNAs) is becoming increasingly apparent, and it appears that there are more than two to three times as many lncRNAs as protein-coding genes. lncRNAs can directly interact with DNA, RNA, and proteins, and a single lncRNA can contain multiple modular domains and thus interact with different classes of molecules. Yet, most lncRNAs have not been tested for function, and even fewer knockout mice have been generated. It is therefore timely to consider new potential mechanisms that may contribute to immune memory.


Assuntos
RNA Longo não Codificante , Animais , Cromatina , Epigenômica , Regulação da Expressão Gênica , Linfócitos , Camundongos , RNA Longo não Codificante/metabolismo
15.
Cancer Immunol Res ; 9(11): 1245-1251, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34544686

RESUMO

Recent success in the use of immunotherapy for a broad range of cancers has propelled the field of cancer immunology to the forefront of cancer research. As more and more young investigators join the community of cancer immunologists, the Arthur L. Irving Family Foundation Cancer Immunology Symposium provided a platform to bring this expanding and vibrant community together and support the development of the future leaders in the field. This commentary outlines the lessons that emerged from the inaugural symposium highlighting the areas of scientific and career development that are essential for professional growth in the field of cancer immunology and beyond. Leading scientists and clinicians in the field provided their experience on the topics of scientific trajectory, career trajectory, publishing, fundraising, leadership, mentoring, and collaboration. Herein, we provide a conceptual and practical framework for career development to the broader scientific community.


Assuntos
Alergia e Imunologia/educação , Pesquisa Biomédica/métodos , Neoplasias/epidemiologia , Médicos/organização & administração , Humanos , Liderança
16.
Environ Entomol ; 50(5): 1045-1055, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34268579

RESUMO

Aphids are important pests of pecans in Georgia. Although previous studies conducted seasonal monitoring of pecan aphids, these studies were done at a single experimental site. In addition, only a few seasonal monitoring studies have tracked pecan aphid mummies parasitized by the aphid parasitoid, Aphelinus perpallidus Gahan. The objective of this study was to assess the seasonal phenology of yellow pecan aphid (Monelliopsis pecanis Bissell), blackmargined aphid [Monellia caryella (Fitch)], black pecan aphid [Melanocallis caryaefoliae (Davis)], aphid mummies, and adult A. perpallidus in four Georgia commercial orchards, with varying aphid management regimes, in 2019 and 2020. Comparison of overall aphid and parasitoid numbers between sites revealed few consistent annual patterns in both years. Aphid seasonal trends were consistent among sites and followed the patterns seen in previous studies, with the yellow aphid complex peaking in May, June, September, and October and black pecan aphids peaking in late September and October. Despite varying levels of insecticide application between sites, aphid phenology followed a similar seasonal pattern and remained low, throughout both growing seasons. This may indicate that growers can apply low frequencies of insecticides and still achieve pecan aphid control. Parasitism numbers were highest in the low insecticide frequency site compared with the other three sites. Mummies varied in their correlation with yellow aphid complex and black pecan aphid numbers. Parasitoid numbers typically followed the cycle of their host throughout the season.


Assuntos
Afídeos , Carya , Inseticidas , Animais , Georgia , Estações do Ano
17.
Cell Host Microbe ; 29(4): 516-521.e3, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33798491

RESUMO

The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies. We compared antibody binding and live virus neutralization of sera from naturally infected and Moderna-vaccinated individuals against two SARS-CoV-2 variants: B.1 containing the spike mutation D614G and the emerging B.1.351 variant containing additional spike mutations and deletions. Sera from acutely infected and convalescent COVID-19 patients exhibited a 3-fold reduction in binding antibody titers to the B.1.351 variant receptor-binding domain of the spike protein and a 3.5-fold reduction in neutralizing antibody titers against SARS-CoV-2 B.1.351 variant compared to the B.1 variant. Similar results were seen with sera from Moderna-vaccinated individuals. Despite reduced antibody titers against the B.1.351 variant, sera from infected and vaccinated individuals containing polyclonal antibodies to the spike protein could still neutralize SARS-CoV-2 B.1.351, suggesting that protective humoral immunity may be retained against this variant.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Sítios de Ligação , COVID-19/prevenção & controle , Humanos , Testes de Neutralização , Receptores Virais/química
19.
bioRxiv ; 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33655254

RESUMO

The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies to neutralize these variants. We compared antibody binding and live virus neutralization of sera from naturally infected and spike mRNA vaccinated individuals against a circulating SARS-CoV-2 B.1 variant and the emerging B.1.351 variant. In acutely-infected (5-19 days post-symptom onset), convalescent COVID-19 individuals (through 8 months post-symptom onset) and mRNA-1273 vaccinated individuals (day 14 post-second dose), we observed an average 4.3-fold reduction in antibody titers to the B.1.351-derived receptor binding domain of the spike protein and an average 3.5-fold reduction in neutralizing antibody titers to the SARS-CoV-2 B.1.351 variant as compared to the B.1 variant (spike D614G). However, most acute and convalescent sera from infected and all vaccinated individuals neutralize the SARS-CoV-2 B.1.351 variant, suggesting that protective immunity is retained against COVID-19.

20.
medRxiv ; 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33564782

RESUMO

Antibody responses against the SARS-CoV-2 Spike protein correlate with protection against COVID-19. Serum neutralizing antibodies appear early after symptom onset following SARS-CoV-2 infection and can last for several months. Similarly, the messenger RNA vaccine, mRNA-1273, generates serum neutralizing antibodies that are detected through at least day 119. However, the recent emergence of the B.1.1.7 variant has raised significant concerns about the breadth of these neutralizing antibody responses. In this study, we used a live virus neutralization assay to compare the neutralization potency of sera from infected and vaccinated individuals against a panel of SARS-CoV-2 variants, including SARS-CoV-2 B.1.1.7. We found that both infection- and vaccine-induced antibodies were effective at neutralizing the SARS-CoV-2 B.1.1.7 variant. These findings support the notion that in the context of the UK variant, vaccine-induced immunity can provide protection against COVID-19. As additional SARS-CoV-2 viral variants continue to emerge, it is crucial to monitor their impact on neutralizing antibody responses following infection and vaccination.

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