Fifth Department of Medicine (Nephrology/Endocrinology/Rheumatology/Pneumology), University Medical Centre Mannheim, University of Heidelberg, Germany; Department of Nephrology, Charité - Universitätsmedizin Berlin, Campus Mitte, Berlin, Germany.
Institute of Medical Diagnostics, IMD Berlin-Potsdam, Berlin, Germany.
Clin Chim Acta. 2022 Jul 1;532:130-136. doi: 10.1016/j.cca.2022.05.025. Epub 2022 Jun 8.
Both infection with and vaccination against SARS-CoV-2 trigger a complex B-cell and T-cell response. Methods for the analysis of the B-cell response are now well established. However, reliable methods for measuring the T-cell response are less well established and their usefulness in clinical settings still needs to be proven. Here, we have developed and validated a T-cell proliferation assay based on 3H thymidine incorporation. The assay is using SARS-CoV-2 derived peptide pools that cover the spike (S), the nucleocapsid (N) and the membrane (M) protein for stimulation. We have compared this novel SARS-CoV-2 lymphocyte transformation test (SARS-CoV-2 LTT) to an established ELISA assay detecting Immunoglobulin G (IgG) antibodies to the S1 subunit of the SARS-CoV-2 spike protein. The study was carried out using blood samples from both vaccinated and infected health care workers as well as from a non-infected control group. Our novel SARS-CoV-2 LTT shows excellent discrimination of infected and/or vaccinated individuals versus unexposed controls, with the ROC analysis showing an area under the curve (AUC) of > 0.95. No false positives were recorded as all unexposed controls had a negative LTT result. When using peptide pools not only representing the S protein (found in all currently approved vaccines) but also the N and M proteins (not contained in the vast majority of vaccines), the novel SARS-CoV-2 LTT can also discriminate T-cell responses resulting from vaccination against those induced by infection.
SARS-CoV-2 的感染和疫苗接种都会引发复杂的 B 细胞和 T 细胞反应。目前已经建立了用于分析 B 细胞反应的方法。然而，用于测量 T 细胞反应的可靠方法还不太完善，其在临床环境中的实用性仍有待证明。在这里，我们开发并验证了一种基于 3H 胸苷掺入的 T 细胞增殖测定法。该测定法使用 SARS-CoV-2 衍生的肽池来刺激刺突 (S)、核衣壳 (N) 和膜 (M) 蛋白。我们将这种新型 SARS-CoV-2 淋巴细胞转化试验 (SARS-CoV-2 LTT) 与一种已建立的 ELISA 测定法进行了比较，该测定法检测针对 SARS-CoV-2 刺突蛋白 S1 亚基的免疫球蛋白 G (IgG) 抗体。该研究使用了来自接种疫苗和感染的医护人员以及未感染对照组的血液样本。我们的新型 SARS-CoV-2 LTT 能够出色地区分感染和/或接种疫苗的个体与未暴露的对照组，ROC 分析显示曲线下面积 (AUC) > 0.95。由于所有未暴露的对照组的 LTT 结果均为阴性，因此没有记录到假阳性。当使用不仅代表 S 蛋白（存在于所有目前批准的疫苗中）而且还代表 N 和 M 蛋白（绝大多数疫苗中均不包含）的肽池时，新型 SARS-CoV-2 LTT 还可以区分疫苗接种引起的 T 细胞反应与感染引起的 T 细胞反应。
