Tsai Dong-Yan, Wang Chun-Hung, Schiro Perry G, Chen Nathan, Tseng Ju-Yu
MiCareo Taiwan Co., Ltd., 5F, No. 69, Ln. 77, Xing Ai Rd., Neihu Dist., Taipei City 114, Taiwan.
Adimmune Corporation, No. 3, Sec.1, Tanxing Rd., Tanzi Dist., Taichung City 427, Taiwan.
Vaccines (Basel). 2023 Mar 26;11(4):735. doi: 10.3390/vaccines11040735.
Rapid mutations within SARS-CoV-2 are driving immune escape, highlighting the need for in-depth and routine analysis of memory B cells (MBCs) to complement the important but limited information from neutralizing antibody (nAb) studies. In this study, we collected plasma samples and peripheral blood mononuclear cells (PBMCs) from 35 subjects and studied the nAb titers and the number of antigen-specific memory B cells at designated time points before and after vaccination. We developed an assay to use the MiSelect R II System with a single-use microfluidic chip to directly detect the number of spike-receptor-binding domain (RBD)-specific MBCs in PBMCs. Our results show that the number of spike-RBD-specific MBCs detected by the MiSelect R II System is highly correlated with the level of nAbs secreted by stimulated PBMCs, even 6 months after vaccination when nAbs were generally not present in plasma. We also found antigen-specific cells recognizing Omicron spike-RBD were present in PBMCs from booster vaccination of subjects, but with a high variability in the number of B cells. The MiSelect R II System provided a direct, automated, and quantitative method to isolate and analyze subsets of rare cells for tracking cellular immunity in the context of a rapidly mutating virus.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的快速突变正在推动免疫逃逸，这凸显了对记忆B细胞（MBC）进行深入和常规分析的必要性，以补充来自中和抗体（nAb）研究的重要但有限的信息。在本研究中，我们收集了35名受试者的血浆样本和外周血单核细胞（PBMC），并研究了疫苗接种前后指定时间点的nAb滴度和抗原特异性记忆B细胞数量。我们开发了一种检测方法，使用带有一次性微流控芯片的MiSelect R II系统直接检测PBMC中刺突受体结合域（RBD）特异性MBC的数量。我们的结果表明，MiSelect R II系统检测到的刺突-RBD特异性MBC数量与受刺激PBMC分泌的nAb水平高度相关，即使在接种疫苗6个月后血浆中通常不存在nAb时也是如此。我们还发现，在接受加强疫苗接种的受试者的PBMC中存在识别奥密克戎刺突-RBD的抗原特异性细胞，但B细胞数量存在很大差异。MiSelect R II系统提供了一种直接、自动化和定量的方法，用于在快速突变病毒的背景下分离和分析稀有细胞亚群以追踪细胞免疫。
