Dentone Chiara, Fenoglio Daniela, Ponzano Marta, Cerchiaro Matteo, Altosole Tiziana, Franciotta Diego, Portunato Federica, Mikulska Malgorzata, Taramasso Lucia, Magnasco Laura, Uras Chiara, Magne Federica, Ferrera Francesca, Scavone Graziana, Signori Alessio, Vena Antonio, Visconti Valeria, Filaci Gilberto, Sette Alessandro, Grifoni Alba, Di Biagio Antonio, Bassetti Matteo
Infectious Disease Clinic, IRCCS Policlinico San Martino Hospital, Largo Rosanna Benzi, 10, 16132 Genoa, Italy.
Department of Internal Medicine, Centre of Excellence for Biomedical Research (CEBR), University of Genoa, 16126 Genoa, Italy.
Vaccines (Basel). 2022 Oct 24;10(11):1784. doi: 10.3390/vaccines10111784.
We prospectively studied immunological response against SARS-CoV-2 after vaccination among healthcare workers without (group A) and with previous infection (group B). The analyses were collected at T0 (before the BNT162b2), T1 (before the second dose), T2 and T6 (1 and 6 months after the second dose). For cellular immune response, the activation-induced cell marker assay was performed with CD4 and CD8 Spike peptide megapools expressed as Stimulation Index. For humoral immune response, we determined antibodies to Spike-1 and nucleocapsid protein. The linear mixed model compared specific times to T0. The CD4+ Spike response overall rate of change was significant at T1 (p = 0.038) and at T2 (p < 0.001), while decreasing at T6. For CD8+ Spike reactivity, the interaction between the time and group was significant (p = 0.0265), and the p value for group comparison was significant at the baseline (p = 0.0030) with higher SI in previously infected subjects. Overall, the anti-S Abs significantly increased from T1 to T6 compared to T0. The group B at T6 retained high anti-S titer (p < 0.001). At T6, in both groups we found a persistent humoral response and a high CD4+ T cell response able to cross recognize SARS-COV-2 variants including epsilon, even if not a circulating virus at that time.
我们前瞻性地研究了未感染过新冠病毒（A组）和既往有感染史（B组）的医护人员接种疫苗后针对严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的免疫反应。在T0（接种BNT162b2疫苗前）、T1（接种第二剂疫苗前）、T2和T6（接种第二剂疫苗后1个月和6个月）收集分析样本。对于细胞免疫反应，采用激活诱导细胞标记检测法检测针对CD4和CD8刺突蛋白多肽池的反应，以刺激指数表示。对于体液免疫反应，我们检测了针对刺突蛋白1和核衣壳蛋白的抗体。采用线性混合模型比较各特定时间点与T0的差异。CD4+刺突反应的总体变化率在T1（p = 0.038）和T2（p < 0.001）时显著，而在T6时下降。对于CD8+刺突反应性，时间与组间的交互作用显著（p = 0.0265），组间比较的p值在基线时显著（p = 0.0030），既往感染的受试者刺激指数更高。总体而言，与T0相比，抗刺突蛋白抗体（anti-S Abs）从T1到T6显著增加。B组在T6时保持高抗刺突蛋白滴度（p < 0.001）。在T6时，两组均发现持续的体液反应和高CD4+ T细胞反应，能够交叉识别包括ε变体在内的SARS-CoV-2变体，即使该变体在当时并非流行病毒。
