Abstract：
BACKGROUND: T cell immunity plays a pivotal role in mitigating the severity of coronavirus disease 2019 (COVID-19). Therefore, reliable functional T cell assays are required to evaluate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell immunity in specific patient populations.
METHODS: We recruited a cohort of 23 healthcare workers who received their bivalent Omicron BA.1 / ancestral mRNA booster vaccination or were infected with the Omicron variant at a median of 144 days and 227 days before blood collection, respectively. In this cohort, we compared the performances of two widely utilized commercial SARS-CoV-2 interferon-gamma release assays (IGRAs), i.e., QuantiFERON SARS-CoV-2 and T-SPOT.COVID, and an in-house designed Omicron enzyme-linked immunospot (ELISpot).
RESULTS: The QuantiFERON SARS-CoV-2 and T-SPOT.COVID assays detected SARS-CoV-2 spike-specific T cells in 34.8 % and 21.7 % of participants, respectively. Moreover, our in-house designed ELISpot that included Omicron BA.4 and BA.5 full-spike peptides detected T cell responses in 47.8 % of participants and was strongly associated with the T-SPOT.COVID.
CONCLUSIONS: The evaluation of SARS-CoV-2 T cell immunity using commercially accessible assays may yield disparate outcomes as results from different assays are not directly comparable. A specific Omicron ELISpot should be considered to assess Omicron-specific T cell immunity.
METHODS: We recruited a cohort of 23 healthcare workers who received their bivalent Omicron BA.1 / ancestral mRNA booster vaccination or were infected with the Omicron variant at a median of 144 days and 227 days before blood collection, respectively. In this cohort, we compared the performances of two widely utilized commercial SARS-CoV-2 interferon-gamma release assays (IGRAs), i.e., QuantiFERON SARS-CoV-2 and T-SPOT.COVID, and an in-house designed Omicron enzyme-linked immunospot (ELISpot).
RESULTS: The QuantiFERON SARS-CoV-2 and T-SPOT.COVID assays detected SARS-CoV-2 spike-specific T cells in 34.8 % and 21.7 % of participants, respectively. Moreover, our in-house designed ELISpot that included Omicron BA.4 and BA.5 full-spike peptides detected T cell responses in 47.8 % of participants and was strongly associated with the T-SPOT.COVID.
CONCLUSIONS: The evaluation of SARS-CoV-2 T cell immunity using commercially accessible assays may yield disparate outcomes as results from different assays are not directly comparable. A specific Omicron ELISpot should be considered to assess Omicron-specific T cell immunity.
摘要：
背景：T细胞免疫在减轻2019年冠状病毒病（COVID-19）的严重程度中起着关键作用。因此,需要可靠的功能性T细胞试验来评估特定患者人群中严重急性呼吸综合征冠状病毒2型(SARS-CoV-2)特异性T细胞免疫.
方法：我们招募了一组23名医护人员，他们在采血前144天和227天的中位数接受了二价OmicronBA.1/祖先mRNA加强疫苗接种或感染了Omicron变体，分别。在这个队列中，我们比较了两种广泛使用的商业SARS-CoV-2干扰素-γ释放试验（IGRAs）的性能，即，QuantiferonSARS-CoV-2和T-SPOT。COVID,和内部设计的Omicron酶联免疫斑点（ELISpot）。
结果：QuantiferonSARS-CoV-2和T-SPOT。COVID检测在34.8%和21.7%的参与者中检测到SARS-CoV-2尖峰特异性T细胞，分别。此外，我们内部设计的ELISpot包括OmicronBA4和BA.5全峰肽,在47.8%的参与者中检测到T细胞应答,并且与T-SPOT密切相关.COVID.
结论：使用商业上可获得的测定法评估SARS-CoV-2T细胞免疫可能会产生不同的结果，因为不同测定法的结果无法直接比较。应考虑使用特定的OmicronELISpot来评估Omicron特异性T细胞免疫。
方法：我们招募了一组23名医护人员，他们在采血前144天和227天的中位数接受了二价OmicronBA.1/祖先mRNA加强疫苗接种或感染了Omicron变体，分别。在这个队列中，我们比较了两种广泛使用的商业SARS-CoV-2干扰素-γ释放试验（IGRAs）的性能，即，QuantiferonSARS-CoV-2和T-SPOT。COVID,和内部设计的Omicron酶联免疫斑点（ELISpot）。
结果：QuantiferonSARS-CoV-2和T-SPOT。COVID检测在34.8%和21.7%的参与者中检测到SARS-CoV-2尖峰特异性T细胞，分别。此外，我们内部设计的ELISpot包括OmicronBA4和BA.5全峰肽,在47.8%的参与者中检测到T细胞应答,并且与T-SPOT密切相关.COVID.
结论：使用商业上可获得的测定法评估SARS-CoV-2T细胞免疫可能会产生不同的结果，因为不同测定法的结果无法直接比较。应考虑使用特定的OmicronELISpot来评估Omicron特异性T细胞免疫。
