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1.
Nature ; 602(7898): 664-670, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35016195

RESUMO

The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Deriva e Deslocamento Antigênicos/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , Testes de Neutralização , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Deriva e Deslocamento Antigênicos/genética , Vacinas contra COVID-19/imunologia , Linhagem Celular , Convalescença , Epitopos de Linfócito B/imunologia , Humanos , Evasão da Resposta Imune , Camundongos , SARS-CoV-2/química , SARS-CoV-2/classificação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Vesiculovirus/genética
2.
Mol Cell ; 71(4): 637-648.e5, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30118682

RESUMO

Although macrophages are armed with potent antibacterial functions, Mycobacterium tuberculosis (Mtb) replicates inside these innate immune cells. Determinants of macrophage intrinsic bacterial control, and the Mtb strategies to overcome them, are poorly understood. To further study these processes, we used an affinity tag purification mass spectrometry (AP-MS) approach to identify 187 Mtb-human protein-protein interactions (PPIs) involving 34 secreted Mtb proteins. This interaction map revealed two factors involved in Mtb pathogenesis-the secreted Mtb protein, LpqN, and its binding partner, the human ubiquitin ligase CBL. We discovered that an lpqN Mtb mutant is attenuated in macrophages, but growth is restored when CBL is removed. Conversely, Cbl-/- macrophages are resistant to viral infection, indicating that CBL regulates cell-intrinsic polarization between antibacterial and antiviral immunity. Collectively, these findings illustrate the utility of this Mtb-human PPI map for developing a deeper understanding of the intricate interactions between Mtb and its host.


Assuntos
Proteínas de Bactérias/genética , HIV/genética , Interações Hospedeiro-Patógeno , Mycobacterium tuberculosis/genética , Proteínas Proto-Oncogênicas c-cbl/genética , Fatores de Virulência/genética , Animais , Proteínas de Bactérias/imunologia , Linhagem Celular Tumoral , Chlamydia trachomatis/genética , Chlamydia trachomatis/imunologia , Regulação da Expressão Gênica , HIV/imunologia , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/imunologia , Humanos , Linfócitos/microbiologia , Linfócitos/virologia , Macrófagos/microbiologia , Macrófagos/virologia , Camundongos , Mycobacterium tuberculosis/imunologia , Cultura Primária de Células , Ligação Proteica , Mapeamento de Interação de Proteínas , Proteínas Proto-Oncogênicas c-cbl/deficiência , Proteínas Proto-Oncogênicas c-cbl/imunologia , Células RAW 264.7 , Transdução de Sinais , Fatores de Virulência/imunologia
3.
Eur J Clin Invest ; 54(6): e14183, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38381530

RESUMO

Large language models (LLMs) are a type of machine learning model that learn statistical patterns over text, such as predicting the next words in a sequence of text. Both general purpose and task-specific LLMs have demonstrated potential across diverse applications. Science and medicine have many data types that are highly suitable for LLMs, such as scientific texts (publications, patents and textbooks), electronic medical records, large databases of DNA and protein sequences and chemical compounds. Carefully validated systems that can understand and reason across all these modalities may maximize benefits. Despite the inevitable limitations and caveats of any new technology and some uncertainties specific to LLMs, LLMs have the potential to be transformative in science and medicine.


Assuntos
Aprendizado de Máquina , Humanos , Registros Eletrônicos de Saúde , Processamento de Linguagem Natural , Medicina , Ciência , Patentes como Assunto
4.
bioRxiv ; 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34931194

RESUMO

The recently emerged SARS-CoV-2 Omicron variant harbors 37 amino acid substitutions in the spike (S) protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody therapeutics. Here, we show that the Omicron RBD binds to human ACE2 with enhanced affinity relative to the Wuhan-Hu-1 RBD and acquires binding to mouse ACE2. Severe reductions of plasma neutralizing activity were observed against Omicron compared to the ancestral pseudovirus for vaccinated and convalescent individuals. Most (26 out of 29) receptor-binding motif (RBM)-directed monoclonal antibodies (mAbs) lost in vitro neutralizing activity against Omicron, with only three mAbs, including the ACE2-mimicking S2K146 mAb 1 , retaining unaltered potency. Furthermore, a fraction of broadly neutralizing sarbecovirus mAbs recognizing antigenic sites outside the RBM, including sotrovimab 2 , S2X259 3 and S2H97 4 , neutralized Omicron. The magnitude of Omicron-mediated immune evasion and the acquisition of binding to mouse ACE2 mark a major SARS-CoV-2 mutational shift. Broadly neutralizing sarbecovirus mAbs recognizing epitopes conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.

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