tetano
Editor, Senior Moderator
Int J Infect Dis
. 2025 Aug 20:108024.
doi: 10.1016/j.ijid.2025.108024. Online ahead of print. High CD4⁺ T-cell Responses in Seronegative Individuals Following SARS-CoV-2 Exposure during a Dormitory Outbreak
Ooiean Teng[SUP] 1 [/SUP], Amy May Lin Quek[SUP] 2 [/SUP], Delicia Shu Qin Ooi[SUP] 3 [/SUP], Suqing Wang[SUP] 1 [/SUP], Lorivie Fragata[SUP] 1 [/SUP], Isabel Xue Qi Ng[SUP] 1 [/SUP], Jianzhou Cui[SUP] 4 [/SUP], Jinmiao Chen[SUP] 5 [/SUP], Mikael Hartman[SUP] 6 [/SUP], Paul Edward Hutchinson[SUP] 7 [/SUP], Paul Anantharajah Tambyah[SUP] 8 [/SUP], Raymond Chee Seong Seet[SUP] 9 [/SUP]
Affiliations
Objectives: We studied individuals who remained uninfected by SARS-CoV-2 despite repeated exposures during a May-July 2020 dormitory outbreak in Singapore.
Methods: We compared immune profiles of those with exposed seronegative (ESN) (negative PCR and serology), with non-infected and infected groups. Following the lifting of quarantine, incident infection rates were compared between the ESN and non-infected cohorts.
Results: The immune profiles of 135 men with ESN (repeated negative PCR and persistent seronegativity), and 98 non-infected men, and 139 infected men were examined (mean age 33 years). Men with ESN exhibited higher percentages of CD4[SUP]+[/SUP] T-cells and classical monocytes, alongside increased specific CD4[SUP]+[/SUP] T cell responses to the non-structural protein 12-3 region (NSP12-3) and spike peptides of SARS-CoV-2, compared with non-infection controls. Those with ESN did not differ in their IgG levels against endemic human coronaviruses compared with non-infection controls. Men in the ESN group were found to be less likely to become infected compared with non-infected controls (21% vs. 39%, hazard ratio 0.47 [95% CI 0.27-0.73]) after the lifting of quarantine measures.
Conclusions: These findings highlight the possible importance of cellular immunity in conferring partial resistance to infection and support the development of T-cell-focused strategies for high-risk settings.
Gov number: NCT04446104.
Keywords: CD4(+) T-cells; SARS-CoV-2; cytokines; exposed seronegative.
. 2025 Aug 20:108024.
doi: 10.1016/j.ijid.2025.108024. Online ahead of print. High CD4⁺ T-cell Responses in Seronegative Individuals Following SARS-CoV-2 Exposure during a Dormitory Outbreak
Ooiean Teng[SUP] 1 [/SUP], Amy May Lin Quek[SUP] 2 [/SUP], Delicia Shu Qin Ooi[SUP] 3 [/SUP], Suqing Wang[SUP] 1 [/SUP], Lorivie Fragata[SUP] 1 [/SUP], Isabel Xue Qi Ng[SUP] 1 [/SUP], Jianzhou Cui[SUP] 4 [/SUP], Jinmiao Chen[SUP] 5 [/SUP], Mikael Hartman[SUP] 6 [/SUP], Paul Edward Hutchinson[SUP] 7 [/SUP], Paul Anantharajah Tambyah[SUP] 8 [/SUP], Raymond Chee Seong Seet[SUP] 9 [/SUP]
Affiliations
- PMID: 40845939
- DOI: 10.1016/j.ijid.2025.108024
Objectives: We studied individuals who remained uninfected by SARS-CoV-2 despite repeated exposures during a May-July 2020 dormitory outbreak in Singapore.
Methods: We compared immune profiles of those with exposed seronegative (ESN) (negative PCR and serology), with non-infected and infected groups. Following the lifting of quarantine, incident infection rates were compared between the ESN and non-infected cohorts.
Results: The immune profiles of 135 men with ESN (repeated negative PCR and persistent seronegativity), and 98 non-infected men, and 139 infected men were examined (mean age 33 years). Men with ESN exhibited higher percentages of CD4[SUP]+[/SUP] T-cells and classical monocytes, alongside increased specific CD4[SUP]+[/SUP] T cell responses to the non-structural protein 12-3 region (NSP12-3) and spike peptides of SARS-CoV-2, compared with non-infection controls. Those with ESN did not differ in their IgG levels against endemic human coronaviruses compared with non-infection controls. Men in the ESN group were found to be less likely to become infected compared with non-infected controls (21% vs. 39%, hazard ratio 0.47 [95% CI 0.27-0.73]) after the lifting of quarantine measures.
Conclusions: These findings highlight the possible importance of cellular immunity in conferring partial resistance to infection and support the development of T-cell-focused strategies for high-risk settings.
Gov number: NCT04446104.
Keywords: CD4(+) T-cells; SARS-CoV-2; cytokines; exposed seronegative.