Department of Biological Science and Biotechnology, Andong National University, Andong, 36729, Korea.
Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, 52727, Korea.
BMC Infect Dis. 2023 Oct 27;23(1):732. doi: 10.1186/s12879-023-08728-5.
We aimed to compare the adaptive immune response in individuals with or without prior SARS-CoV-2 infections following the administration of mRNA-based COVID-19 vaccines.
A total of 54 participants with ages ranging from 37 to 56 years old, consisting of 23 individuals without a history of SARS-CoV-2 infection (uninfected group) and 31 individuals with prior infection of SARS-CoV-2 (infected group) who have received two doses of mRNA SARS-CoV-2 vaccines were enrolled in this study. We measured the IFN-γ level upon administration of BNT162b2 (PF) or mRNA-1273 (MO) by QuantiFERON SARS-CoV-2. The production of neutralizing antibodies was evaluated by a surrogate virus neutralization assay, and the neutralizing capacity was assessed by a plaque reduction neutralization test (PRNT). The immune response was compared between the two groups.
A significantly higher level of IFN-γ (p < 0.001) and neutralization antibodies (p < 0.001) were observed in the infected group than those in the uninfected group following the first administration of vaccines. The infected group demonstrated a significantly higher PRNT titer than the uninfected group against the Wuhan strain (p < 0.0001). Still, the two groups were not significantly different against Delta (p = 0.07) and Omicron (p = 0.14) variants. Following the second vaccine dose, T- and B-cell levels were not significantly increased in the infected group.
A single dose of mRNA-based COVID-19 vaccines would boost immune responses in individuals who had previously contracted SARS-CoV-2.
本研究旨在比较既往感染 SARS-CoV-2 人群与无感染史人群在接种 mRNA 新冠疫苗后的适应性免疫反应。
本研究共纳入 54 名年龄在 37 至 56 岁之间的参与者，其中 23 名无 SARS-CoV-2 感染史（未感染组），31 名既往感染过 SARS-CoV-2（感染组），均接种了两剂 mRNA SARS-CoV-2 疫苗。我们通过 QuantiFERON SARS-CoV-2 检测接种 BNT162b2（PF）或 mRNA-1273（MO）时 IFN-γ 的水平。通过假病毒中和试验评估中和抗体的产生，并用蚀斑减少中和试验（PRNT）评估中和能力。比较两组间的免疫反应。
与未感染组相比，感染组在接种疫苗后首次给药时 IFN-γ（p<0.001）和中和抗体（p<0.001）水平显著升高。感染组对武汉株的 PRNT 滴度显著高于未感染组（p<0.0001）。然而，两组对 Delta（p=0.07）和 Omicron（p=0.14）变异株的差异无统计学意义。接种第二剂疫苗后，感染组 T 细胞和 B 细胞水平无显著升高。
单次接种 mRNA 新冠疫苗可增强既往感染 SARS-CoV-2 人群的免疫反应。
