tetano
Editor, Senior Moderator
PLoS Pathog
. 2022 May 26;18(5):e1010359.
doi: 10.1371/journal.ppat.1010359. Online ahead of print.
SARS-CoV-2-specific T cells associate with inflammation and reduced lung function in pulmonary post-acute sequalae of SARS-CoV-2
Katherine M Littlefield[SUP] 1 [/SUP], Renée O Watson[SUP] 1 [/SUP], Jennifer M Schneider[SUP] 1 [/SUP], Charles P Neff[SUP] 1 [/SUP], Eiko Yamada[SUP] 1 [/SUP], Min Zhang[SUP] 1 [/SUP], Thomas B Campbell[SUP] 1 [/SUP], Michael T Falta[SUP] 1 [/SUP], Sarah E Jolley[SUP] 1 [/SUP], Andrew P Fontenot[SUP] 1 2 [/SUP], Brent E Palmer[SUP] 1 [/SUP]
Affiliations
Abstract
As of January 2022, at least 60 million individuals are estimated to develop post-acute sequelae of SARS-CoV-2 (PASC) after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While elevated levels of SARS-CoV-2-specific T cells have been observed in non-specific PASC, little is known about their impact on pulmonary function which is compromised in the majority of these individuals. This study compares frequencies of SARS-CoV-2-specific T cells and inflammatory markers with lung function in participants with pulmonary PASC and resolved COVID-19 (RC). Compared to RC, participants with respiratory PASC had between 6- and 105-fold higher frequencies of IFN-γ- and TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells in peripheral blood, and elevated levels of plasma CRP and IL-6. Importantly, in PASC participants the frequency of TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells, which exhibited the highest levels of Ki67 indicating they were activity dividing, correlated positively with plasma IL-6 and negatively with measures of lung function, including forced expiratory volume in one second (FEV1), while increased frequencies of IFN-γ-producing SARS-CoV-2-specific T cells associated with prolonged dyspnea. Statistical analyses stratified by age, number of comorbidities and hospitalization status demonstrated that none of these factors affect differences in the frequency of SARS-CoV-2 T cells and plasma IL-6 levels measured between PASC and RC cohorts. Taken together, these findings demonstrate elevated frequencies of SARS-CoV-2-specific T cells in individuals with pulmonary PASC are associated with increased systemic inflammation and decreased lung function, suggesting that SARS-CoV-2-specific T cells contribute to lingering pulmonary symptoms. These findings also provide mechanistic insight on the pathophysiology of PASC that can inform development of potential treatments to reduce symptom burden.
. 2022 May 26;18(5):e1010359.
doi: 10.1371/journal.ppat.1010359. Online ahead of print.
SARS-CoV-2-specific T cells associate with inflammation and reduced lung function in pulmonary post-acute sequalae of SARS-CoV-2
Katherine M Littlefield[SUP] 1 [/SUP], Renée O Watson[SUP] 1 [/SUP], Jennifer M Schneider[SUP] 1 [/SUP], Charles P Neff[SUP] 1 [/SUP], Eiko Yamada[SUP] 1 [/SUP], Min Zhang[SUP] 1 [/SUP], Thomas B Campbell[SUP] 1 [/SUP], Michael T Falta[SUP] 1 [/SUP], Sarah E Jolley[SUP] 1 [/SUP], Andrew P Fontenot[SUP] 1 2 [/SUP], Brent E Palmer[SUP] 1 [/SUP]
Affiliations
- PMID: 35617421
- DOI: 10.1371/journal.ppat.1010359
Abstract
As of January 2022, at least 60 million individuals are estimated to develop post-acute sequelae of SARS-CoV-2 (PASC) after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While elevated levels of SARS-CoV-2-specific T cells have been observed in non-specific PASC, little is known about their impact on pulmonary function which is compromised in the majority of these individuals. This study compares frequencies of SARS-CoV-2-specific T cells and inflammatory markers with lung function in participants with pulmonary PASC and resolved COVID-19 (RC). Compared to RC, participants with respiratory PASC had between 6- and 105-fold higher frequencies of IFN-γ- and TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells in peripheral blood, and elevated levels of plasma CRP and IL-6. Importantly, in PASC participants the frequency of TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells, which exhibited the highest levels of Ki67 indicating they were activity dividing, correlated positively with plasma IL-6 and negatively with measures of lung function, including forced expiratory volume in one second (FEV1), while increased frequencies of IFN-γ-producing SARS-CoV-2-specific T cells associated with prolonged dyspnea. Statistical analyses stratified by age, number of comorbidities and hospitalization status demonstrated that none of these factors affect differences in the frequency of SARS-CoV-2 T cells and plasma IL-6 levels measured between PASC and RC cohorts. Taken together, these findings demonstrate elevated frequencies of SARS-CoV-2-specific T cells in individuals with pulmonary PASC are associated with increased systemic inflammation and decreased lung function, suggesting that SARS-CoV-2-specific T cells contribute to lingering pulmonary symptoms. These findings also provide mechanistic insight on the pathophysiology of PASC that can inform development of potential treatments to reduce symptom burden.