期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2014
卷号：111
期号：31
页码：E3224-E3233
DOI：10.1073/pnas.1323985111
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Recent studies have demonstrated important roles of nucleic acid-sensing Toll-like receptors (TLRs) in promoting protective antibody responses against several viruses. To dissect how recognition of nucleic acids by TLRs enhances germinal center (GC) responses, mice selectively deleted for myeloid differentiation primary-response protein 88 (MyD88) in B cells or dendritic cells (DCs) were immunized with a haptenated protein antigen bound to a TLR9 ligand. TLR9 signaling in DCs led to greater numbers of follicular helper T (TFH) cells and GC B cells, and accelerated production of broad-affinity antihapten IgG. In addition to modulating GC selection by increasing inducible costimulator (ICOS) expression on TFH cells and reducing the number of follicular regulatory T cells, MyD88-dependent signaling in B cells enhanced GC output by augmenting a class switch to IgG2a, affinity maturation, and the memory antibody response. Thus, attachment of a TLR9 ligand to an oligovalent antigen acted on DCs and B cells to coordinate changes in the T-cell compartment and also promoted B cell-intrinsic effects that ultimately programmed a more potent GC response.
