Ahmed Mohamed I M, Plank Michael, Castelletti Noemi, Diepers Paulina, Eser Tabea M, Rubio-Acero Raquel, Noreña Ivan, Reinkemeyer Christina, Zapf Dorinja, Hoelscher Michael, Janke Christian, Wieser Andreas, Geldmacher Christof
Division of Infectious Diseases and Tropical Medicine, University Hospital, LMU Munich, 80802 Munich, Germany.
German Center for Infection Research (DZIF), Partner Site Munich, 81675 Munich, Germany.
Diagnostics (Basel). 2023 Mar 8;13(6):1024. doi: 10.3390/diagnostics13061024.
The currently prevailing variants of SARS-CoV-2 are subvariants of the Omicron variant. The aim of this study was to analyze the effect of mutations in the Spike protein of Omicron on the results Quan-T-Cell SARS-CoV-2 assays and Roche Elecsys anti-SARS-CoV-2 anti-S1. Omicron infected subjects (( = 37), vaccinated ( = 20) and unvaccinated ( = 17)) were recruited approximately 3 weeks after a positive PCR test. The Quan-T-Cell SARS-CoV-2 assays (EUROIMMUN) using Wuhan and the Omicron adapted antigen assay and a serological test (Roche Elecsys anti-SARS-CoV-2 anti-S1) were performed. Using the original Wuhan SARS-CoV-2 IGRA TUBE, in 19 of 21 tested Omicron infected subjects, a positive IFNy response was detected, while 2 non-vaccinated but infected subjects did not respond. The Omicron adapted antigen tube resulted in comparable results. In contrast, the serological assay detected a factor 100-fold lower median Spike-specific RBD antibody concentration in non-vaccinated Omicron infected patients ( = 12) compared to patients from the pre Omicron era ( = 12) at matched time points, and eight individuals remained below the detection threshold for positivity. For vaccinated subjects, the Roche assay detected antibodies in all subjects and showed a 400 times higher median specific antibody concentration compared to non-vaccinated infected subjects in the pre-Omicron era. Our results suggest that Omicron antigen adapted IGRA stimulator tubes did not improve detection of SARS-CoV-2-specific T-cell responses in the Quant-T-Cell-SARS-CoV-2 assay. In non-vaccinated Omicron infected individuals, the Wuhan based Elecsys anti-SARS-CoV-2 anti-S1 serological assay results in many negative results at 3 weeks after diagnosis.
目前流行的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）变体是奥密克戎变体的亚变体。本研究的目的是分析奥密克戎刺突蛋白中的突变对全T细胞SARS-CoV-2检测和罗氏电化学发光抗SARS-CoV-2抗S1检测结果的影响。在PCR检测呈阳性后约3周招募了奥密克戎感染受试者（n = 37，其中接种疫苗者n = 20，未接种疫苗者n = 17）。进行了使用武汉株和奥密克戎适配抗原检测的全T细胞SARS-CoV-2检测（欧蒙免疫）以及一项血清学检测（罗氏电化学发光抗SARS-CoV-2抗S1）。使用原始的武汉SARS-CoV-2 IGRA检测管，在21名接受检测的奥密克戎感染受试者中有19名检测到阳性的干扰素γ（IFNy）反应，而2名未接种疫苗但感染的受试者无反应。奥密克戎适配抗原检测管得到了类似结果。相比之下，在匹配时间点，血清学检测发现未接种疫苗的奥密克戎感染患者（n = 12）的刺突特异性RBD抗体中位浓度比奥密克戎出现前时代的患者（n = 12）低100倍，并且有8人低于阳性检测阈值。对于接种疫苗的受试者，罗氏检测在所有受试者中均检测到抗体，并且与奥密克戎出现前时代未接种疫苗的感染受试者相比，特异性抗体中位浓度高400倍。我们的结果表明，奥密克戎抗原适配的IGRA刺激管在全T细胞SARS-CoV-2检测中并未改善对SARS-CoV-2特异性T细胞反应的检测。在未接种疫苗的奥密克戎感染个体中，基于武汉株的罗氏电化学发光抗SARS-CoV--2抗S1血清学检测在诊断后3周时出现许多阴性结果。
