tetano
Editor, Senior Moderator
Nat Commun
. 2022 Jan 10;13(1):80.
doi: 10.1038/s41467-021-27674-x.
Cross-reactive memory T cells associate with protection against SARS-CoV-2 infection in COVID-19 contacts
Rhia Kundu[SUP] 1 2 [/SUP], Janakan Sam Narean[SUP] 3 4 [/SUP], Lulu Wang[SUP] 3 4 [/SUP], Joseph Fenn[SUP] 3 4 [/SUP], Timesh Pillay[SUP] 3 4 [/SUP], Nieves Derqui Fernandez[SUP] 3 4 [/SUP], Emily Conibear[SUP] 3 4 [/SUP], Aleksandra Koycheva[SUP] 3 4 [/SUP], Megan Davies[SUP] 3 4 [/SUP], Mica Tolosa-Wright[SUP] 3 4 [/SUP], Seran Hakki[SUP] 3 4 [/SUP], Robert Varro[SUP] 3 4 [/SUP], Eimear McDermott[SUP] 3 4 [/SUP], Sarah Hammett[SUP] 3 4 [/SUP], Jessica Cutajar[SUP] 3 4 [/SUP], Ryan S Thwaites[SUP] 4 [/SUP], Eleanor Parker[SUP] 5 [/SUP], Carolina Rosadas[SUP] 5 [/SUP], Myra McClure[SUP] 5 [/SUP], Richard Tedder[SUP] 5 [/SUP], Graham P Taylor[SUP] 5 [/SUP], Jake Dunning[SUP] 6 7 [/SUP], Ajit Lalvani[SUP] 3 4 [/SUP]
Affiliations
Abstract
Cross-reactive immune responses to SARS-CoV-2 have been observed in pre-pandemic cohorts and proposed to contribute to host protection. Here we assess 52 COVID-19 household contacts to capture immune responses at the earliest timepoints after SARS-CoV-2 exposure. Using a dual cytokine FLISpot assay on peripheral blood mononuclear cells, we enumerate the frequency of T cells specific for spike, nucleocapsid, membrane, envelope and ORF1 SARS-CoV-2 epitopes that cross-react with human endemic coronaviruses. We observe higher frequencies of cross-reactive (p = 0.0139), and nucleocapsid-specific (p = 0.0355) IL-2-secreting memory T cells in contacts who remained PCR-negative despite exposure (n = 26), when compared with those who convert to PCR-positive (n = 26); no significant difference in the frequency of responses to spike is observed, hinting at a limited protective function of spike-cross-reactive T cells. Our results are thus consistent with pre-existing non-spike cross-reactive memory T cells protecting SARS-CoV-2-naïve contacts from infection, thereby supporting the inclusion of non-spike antigens in second-generation vaccines.
. 2022 Jan 10;13(1):80.
doi: 10.1038/s41467-021-27674-x.
Cross-reactive memory T cells associate with protection against SARS-CoV-2 infection in COVID-19 contacts
Rhia Kundu[SUP] 1 2 [/SUP], Janakan Sam Narean[SUP] 3 4 [/SUP], Lulu Wang[SUP] 3 4 [/SUP], Joseph Fenn[SUP] 3 4 [/SUP], Timesh Pillay[SUP] 3 4 [/SUP], Nieves Derqui Fernandez[SUP] 3 4 [/SUP], Emily Conibear[SUP] 3 4 [/SUP], Aleksandra Koycheva[SUP] 3 4 [/SUP], Megan Davies[SUP] 3 4 [/SUP], Mica Tolosa-Wright[SUP] 3 4 [/SUP], Seran Hakki[SUP] 3 4 [/SUP], Robert Varro[SUP] 3 4 [/SUP], Eimear McDermott[SUP] 3 4 [/SUP], Sarah Hammett[SUP] 3 4 [/SUP], Jessica Cutajar[SUP] 3 4 [/SUP], Ryan S Thwaites[SUP] 4 [/SUP], Eleanor Parker[SUP] 5 [/SUP], Carolina Rosadas[SUP] 5 [/SUP], Myra McClure[SUP] 5 [/SUP], Richard Tedder[SUP] 5 [/SUP], Graham P Taylor[SUP] 5 [/SUP], Jake Dunning[SUP] 6 7 [/SUP], Ajit Lalvani[SUP] 3 4 [/SUP]
Affiliations
- PMID: 35013199
- DOI: 10.1038/s41467-021-27674-x
Abstract
Cross-reactive immune responses to SARS-CoV-2 have been observed in pre-pandemic cohorts and proposed to contribute to host protection. Here we assess 52 COVID-19 household contacts to capture immune responses at the earliest timepoints after SARS-CoV-2 exposure. Using a dual cytokine FLISpot assay on peripheral blood mononuclear cells, we enumerate the frequency of T cells specific for spike, nucleocapsid, membrane, envelope and ORF1 SARS-CoV-2 epitopes that cross-react with human endemic coronaviruses. We observe higher frequencies of cross-reactive (p = 0.0139), and nucleocapsid-specific (p = 0.0355) IL-2-secreting memory T cells in contacts who remained PCR-negative despite exposure (n = 26), when compared with those who convert to PCR-positive (n = 26); no significant difference in the frequency of responses to spike is observed, hinting at a limited protective function of spike-cross-reactive T cells. Our results are thus consistent with pre-existing non-spike cross-reactive memory T cells protecting SARS-CoV-2-naïve contacts from infection, thereby supporting the inclusion of non-spike antigens in second-generation vaccines.
