Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA.
Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA; Charité Universitätsmedizin, 10117 Berlin, Germany.
Cell. 2020 Nov 25;183(5):1298-1311.e11. doi: 10.1016/j.cell.2020.09.063. Epub 2020 Oct 29.
Immunological memory is required for protection against repeated infections and is the basis of all effective vaccines. Antibodies produced by memory B cells play an essential role in many of these responses. We have combined lineage tracing with antibody cloning from single B cells to examine the role of affinity in B cell selection into germinal centers (GCs) and the memory B cell compartment in mice immunized with an HIV-1 antigen. We find that contemporaneously developing memory and GC B cells differ in their affinity for antigen throughout the immune response. Whereas GC cells and their precursors are enriched in antigen binding, memory B cells are not. Thus, the polyclonal memory B cell compartment is composed of B cells that were activated during the immune response but whose antigen binding affinity failed to support further clonal expansion in the GC.
免疫记忆是预防反复感染所必需的，也是所有有效疫苗的基础。记忆 B 细胞产生的抗体在许多这些反应中起着至关重要的作用。我们将谱系追踪与单个 B 细胞的抗体克隆相结合，以研究在 HIV-1 抗原免疫的小鼠中，亲和力在 B 细胞选择进入生发中心 (GC) 和记忆 B 细胞区室中的作用。我们发现，在整个免疫反应中，同时发育的记忆 B 细胞和 GC B 细胞在其对抗原的亲和力上存在差异。尽管 GC 细胞及其前体富含抗原结合，但记忆 B 细胞并非如此。因此，多克隆记忆 B 细胞区室由在免疫反应中被激活的 B 细胞组成，但它们的抗原结合亲和力未能支持在 GC 中进一步的克隆扩增。
