RESUMO
BACKGROUND: COVID-19 can present with lymphopenia and extraordinary complex multiorgan pathologies that can trigger long-term sequela. AIMS: Given that inflammasome products, like caspase-1, play a role in the pathophysiology of a number of co-morbid conditions, we investigated caspases across the spectrum of COVID-19 disease. MATERIALS & METHODS: We assessed transcriptional states of multiple caspases and using flow cytometry, the expression of active caspase-1 in blood cells from COVID-19 patients in acute and convalescent stages of disease. Non-COVID-19 subject presenting with various comorbid conditions served as controls. RESULTS: Single-cell RNA-seq data of immune cells from COVID-19 patients showed a distinct caspase expression pattern in T cells, neutrophils, dendritic cells, and eosinophils compared with controls. Caspase-1 was upregulated in CD4+ T-cells from hospitalized COVID-19 patients compared with unexposed controls. Post-COVID-19 patients with lingering symptoms (long-haulers) also showed upregulated caspase-1activity in CD4+ T-cells that ex vivo was attenuated with a select pan-caspase inhibitor. We observed elevated caspase-3/7levels in red blood cells from COVID-19 patients compared with controls that was reduced following caspase inhibition. DISCUSSION: Our preliminary results suggest an exuberant caspase response in COVID-19 that may facilitate immune-related pathological processes leading to severe outcomes. Further clinical correlations of caspase expression in different stages of COVID-19 will be needed. CONCLUSION: Pan-caspase inhibition could emerge as a therapeutic strategy to ameliorate or prevent severe COVID-19.
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Inibidores de Caspase , Linfócitos T CD4-Positivos , COVID-19/complicações , Caspase 1 , Caspase 3 , Caspase 7 , Inibidores de Caspase/uso terapêutico , Caspases/genética , Humanos , Síndrome de COVID-19 Pós-AgudaRESUMO
Development of antibody protection during SARS-CoV-2 infection is a pressing question for public health and for vaccine development. We developed highly sensitive SARS-CoV-2-specific antibody and neutralization assays. SARS-CoV-2 Spike protein or Nucleocapsid protein specific IgG antibodies at titers more than 1:100,000 were detectable in all PCR+ subjects (n = 115) and were absent in the negative controls. Other isotype antibodies (IgA, IgG1-4) were also detected. SARS-CoV-2 neutralization was determined in COVID-19 and convalescent plasma at up to 10,000-fold dilution, using Spike protein pseudotyped lentiviruses, which were also blocked by neutralizing antibodies (NAbs). Hospitalized patients had up to 3000-fold higher antibody and neutralization titers compared to outpatients or convalescent plasma donors. Interestingly, some COVID-19 patients also possessed NAbs against SARS-CoV Spike protein pseudovirus. Together these results demonstrate the high specificity and sensitivity of our assays, which may impact understanding the quality or duration of the antibody response during COVID-19 and in determining the effectiveness of potential vaccines.
Assuntos
Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo de Coronavírus/química , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Adulto , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , COVID-19/imunologia , COVID-19/virologia , Convalescença , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Feminino , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Soros Imunes/química , Imunidade Humoral , Lentivirus/genética , Lentivirus/imunologia , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Fosfoproteínas/química , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/imunologia , Receptores Virais/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Análise de SobrevidaRESUMO
Development of antibody protection during SARS-CoV-2 infection is a pressing question for public health and for vaccine development. We developed highly sensitive SARS-CoV-2-specific antibody and neutralization assays. SARS-CoV-2 Spike protein or Nucleocapsid protein specific IgG antibodies at titers more than 1:100,000 were detectable in all PCR+ subjects (n=115) and were absent in the negative controls. Other isotype antibodies (IgA, IgG1-4) were also detected. SARS-CoV-2 neutralization was determined in COVID-19 and convalescent plasma at up to 10,000-fold dilution, using Spike protein pseudotyped lentiviruses, which were also blocked by neutralizing antibodies (NAbs). Hospitalized patients had up to 3000-fold higher antibody and neutralization titers compared to outpatients or convalescent plasma donors. Interestingly, some COVID-19 patients also possessed NAbs against SARS-CoV Spike protein pseudovirus. Together these results demonstrate the high specificity and sensitivity of our assays, which may impact understanding the quality or duration of the antibody response during COVID-19 and in determining the effectiveness of potential vaccines.
