SARS-CoV-2 recombinant proteins stimulate distinct cellular and humoral immune response profiles in samples from COVID-19 convalescent patients

• Autor(a) principal: Silva, Laís Teodoro da
• Data de Publicação: 2023
• Outros Autores: Ortega, Marina Mazzilli, Tiyo, Bruna Tiaki, Viana, Isabelle Freire Tabosa, Lima, Tayná Evily de, Tozetto-Mendoza, Tania Regina, Oliveira, Luanda Mara da Silva, Teixeira, Franciane Mouradian Emidio, Lins, Roberto Dias, Almeida, Alexandre de, Mendes-Correa, Maria Cassia, Duarte, Alberto Jose da Silva, Oshiro, Telma Miyuki
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Clinics
• Texto Completo: https://www.revistas.usp.br/clinics/article/view/212995
• topic: SARS-CoV-2; COVID-19; Antigens; Immune Response

OBJECTIVES: In this preliminary study we investigated cellular and humoral immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens in blood samples from 14 recovered coronavirus disease 2019 (COVID-19) patients and compared them to those in samples from 12 uninfected/unvaccinated volunteers. METHODS: Cellular immunity was assessed by intracellular detection of IFN-γ in CD3+ T lymphocytes after stimulation with SARS-CoV-2 spike (S1), nucleocapsid (NC), or receptor-binding domain (RBD) recombinant proteins or overlapping peptide pools covering the sequence of SARS-CoV-2 spike, membrane and nucleocapsid regions. The humoral response was examined by ELISAs and/or chemiluminescence assays for the presence of serum IgG antibodies directed to SARS-CoV-2 proteins. RESULTS: We observed differences between humoral and cellular immune profiles in response to stimulation with the same proteins. Assays of IgG antibodies directed to SARS-CoV-2 NC, RBD and S1/S2 recombinant proteins were able to differentiate convalescent from uninfected/unvaccinated groups. Cellular immune responses to SARS-CoV-2 protein stimuli did not exhibit a specific response, as T cells from both individuals with no history of contact with SARS-CoV-2 and from recovered donors were able to produce IFN-γ. CONCLUSIONS: Determination of the cellular immune response to stimulation with a pool of SARS-CoV-2 peptides but not with SARS-CoV-2 proteins is able to distinguish convalescent individuals from unexposed individuals. Regarding the humoral immune response, the screening for serum IgG antibodies directed to SARS-CoV-2 proteins has been shown to be specific for the response of recovered individuals.