Identification of Bcl-6-dependent follicular helper NKT cells that provide cognate help for B cell responses.

Journal article

Lipid antigens trigger help from natural killer T cells (NKT cells) for B cells, and direct conjugation of lipid agonists to antigen profoundly augments antibody responses. Here we show that in vivo, NKT cells engaged in stable and prolonged cognate interactions with B cells and induced the formation of early germinal centers. Mouse and human NKT cells formed CXCR5(+)PD-1(hi) follicular helper NKT cells (NKT(FH) cells), and this process required expression of the transcriptional repressor Bcl-6, signaling via the coreceptor CD28 and interaction with B cells. NKT(FH) cells provided direct cognate help to antigen-specific B cells that was dependent on interleukin 21 (IL-21). Unlike T cell-dependent germinal centers, those driven by NKT(FH) cells did not generate long-lived plasma cells. Our results demonstrate the existence of a Bcl-6-dependent subset of NKT cells specialized in providing help to B cells.

Authors: Chang, P; Barral, P; Fitch, J; Pratama, A; Ma, C

• Publication status: Published
• Journal: Nature immunology
• Volume: 13
• Issue: 1
• Pages: 35-43
• Publication date: 2012-01-01
• DOI: 10.1038/ni.2166
• EISSN: 1529-2916
• ISSN: 1529-2908
• Language: English
• Keywords: Humans; Germinal Center; Mice, Knockout; B-Lymphocytes; Phenotype; Cells, Cultured; Mice, Inbred C57BL; Mice; Immunophenotyping; Animals; Natural Killer T-Cells; Cell Communication; Interleukins; Proto-Oncogene Proteins c-bcl-6; T-Lymphocytes, Helper-Inducer