tetano
Editor, Senior Moderator
J Allergy Clin Immunol
. 2021 Sep 15;S0091-6749(21)01392-0.
doi: 10.1016/j.jaci.2021.09.008. Online ahead of print.
Immunological memory to SARS-CoV-2 in convalescent COVID-19 patients at one-year post-infection
Hongyan Hou[SUP] 1 [/SUP], Yandi Zhang[SUP] 2 [/SUP], Guoxing Tang[SUP] 1 [/SUP], Ying Luo[SUP] 1 [/SUP], Wei Liu[SUP] 1 [/SUP], Chang Cheng[SUP] 3 [/SUP], Yuhuan Jiang[SUP] 4 [/SUP], Zhigang Xiong[SUP] 1 [/SUP], Shiji Wu[SUP] 5 [/SUP], Ziyong Sun[SUP] 6 [/SUP], Shabei Xu[SUP] 7 [/SUP], Xionglin Fan[SUP] 8 [/SUP], Feng Wang[SUP] 9 [/SUP]
Affiliations
Abstract
Background: Understanding the complexities of immune memory to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is key to gain insights into the durability of protective immunity against reinfection.
Objective: To evaluate the immune memory to SARS-CoV-2 in convalescent patients with longer follow-up time.
Methods: SARS-CoV-2-specific humoral and cellular responses were assessed in convalescent coronavirus disease 2019 (COVID-19) patients at one-year post-infection.
Results: A total of 78 convalescent COVID-19 patients (26 moderate, 43 severe, and 9 critical) were recruited after one year of recovery. The positive rates of both anti-RBD and anti-N antibodies were 100%, whereas we did not observe a statistical difference in antibody levels among different severity groups. Accordingly, the prevalence of neutralizing antibodies (nAbs) reached 93.59% in convalescent patients. Although nAb titres displayed an increasing trend in convalescent patients with increased severity, the difference failed to achieve statistical significance. Notably, there was a significant correlation between nAb titres and anti-RBD levels. Interestingly, SARS-CoV-2-specific T cells could be robustly maintained in convalescent patients, and the number of them was positively correlated with both nAb titres and anti-RBD levels. Amplified SARS-CoV-2-specific CD4[SUP]+[/SUP] T cells mainly produced a single cytokine, accompanying with increased expression of exhaustion markers including PD-1, Tim-3, TIGIT, CTLA-4 and CD39, while the proportion of multifunctional cells was low.
Conclusions: Robust SARS-CoV-2-specific humoral and cellular responses are maintained in convalescent COVID-19 patients at one-year post-infection. However, the dysfunction of SARS-CoV-2-specific CD4[SUP]+[/SUP] T cells supports the notion that vaccination is needed in convalescent patients for preventing reinfection.
Keywords: CD4(+) T cell responses; COVID-19; SARS-CoV-2; immune memory; neutralizing antibodies.
. 2021 Sep 15;S0091-6749(21)01392-0.
doi: 10.1016/j.jaci.2021.09.008. Online ahead of print.
Immunological memory to SARS-CoV-2 in convalescent COVID-19 patients at one-year post-infection
Hongyan Hou[SUP] 1 [/SUP], Yandi Zhang[SUP] 2 [/SUP], Guoxing Tang[SUP] 1 [/SUP], Ying Luo[SUP] 1 [/SUP], Wei Liu[SUP] 1 [/SUP], Chang Cheng[SUP] 3 [/SUP], Yuhuan Jiang[SUP] 4 [/SUP], Zhigang Xiong[SUP] 1 [/SUP], Shiji Wu[SUP] 5 [/SUP], Ziyong Sun[SUP] 6 [/SUP], Shabei Xu[SUP] 7 [/SUP], Xionglin Fan[SUP] 8 [/SUP], Feng Wang[SUP] 9 [/SUP]
Affiliations
- PMID: 34536418
- PMCID: PMC8440318
- DOI: 10.1016/j.jaci.2021.09.008
Abstract
Background: Understanding the complexities of immune memory to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is key to gain insights into the durability of protective immunity against reinfection.
Objective: To evaluate the immune memory to SARS-CoV-2 in convalescent patients with longer follow-up time.
Methods: SARS-CoV-2-specific humoral and cellular responses were assessed in convalescent coronavirus disease 2019 (COVID-19) patients at one-year post-infection.
Results: A total of 78 convalescent COVID-19 patients (26 moderate, 43 severe, and 9 critical) were recruited after one year of recovery. The positive rates of both anti-RBD and anti-N antibodies were 100%, whereas we did not observe a statistical difference in antibody levels among different severity groups. Accordingly, the prevalence of neutralizing antibodies (nAbs) reached 93.59% in convalescent patients. Although nAb titres displayed an increasing trend in convalescent patients with increased severity, the difference failed to achieve statistical significance. Notably, there was a significant correlation between nAb titres and anti-RBD levels. Interestingly, SARS-CoV-2-specific T cells could be robustly maintained in convalescent patients, and the number of them was positively correlated with both nAb titres and anti-RBD levels. Amplified SARS-CoV-2-specific CD4[SUP]+[/SUP] T cells mainly produced a single cytokine, accompanying with increased expression of exhaustion markers including PD-1, Tim-3, TIGIT, CTLA-4 and CD39, while the proportion of multifunctional cells was low.
Conclusions: Robust SARS-CoV-2-specific humoral and cellular responses are maintained in convalescent COVID-19 patients at one-year post-infection. However, the dysfunction of SARS-CoV-2-specific CD4[SUP]+[/SUP] T cells supports the notion that vaccination is needed in convalescent patients for preventing reinfection.
Keywords: CD4(+) T cell responses; COVID-19; SARS-CoV-2; immune memory; neutralizing antibodies.