Identification of IFN-γ-producing innate B cells.

Abstract

Although B cells play important roles in the humoral immune response and the regulation of adaptive immunity, B cell subpopulations with unique phenotypes, particularly those with non-classical immune functions, should be further investigated. By challenging mice with Listeria monocytogenes, Escherichia coli, vesicular stomatitis virus and Toll-like receptor ligands, we identified an inducible CD11a(hi)FcγRIII(hi) B cell subpopulation that is significantly expanded and produces high levels of IFN-γ during the early stage of the immune response. This subpopulation of B cells can promote macrophage activation via generating IFN-γ, thereby facilitating the innate immune response against intracellular bacterial infection. As this new subpopulation is of B cell origin and exhibits the phenotypic characteristics of B cells, we designated these cells as IFN-γ-producing innate B cells. Dendritic cells were essential for the inducible generation of these innate B cells from the follicular B cells via CD40L-CD40 ligation. Increased Bruton's tyrosine kinase activation was found to be responsible for the increased activation of non-canonical NF-κB pathway in these innate B cells after CD40 ligation, with the consequent induction of additional IFN-γ production. The identification of this new population of innate B cells may contribute to a better understanding of B cell functions in anti-infection immune responses and immune regulation.

• Authors: Yan Bao, Xingguang Liu, Chaofeng Han, Sheng Xu, Bin Xie, Qian Zhang, Yan Gu, Jin Hou, Li Qian, Cheng Qian, Huanxing Han, Xuetao Cao
• Journal: Cell research (Cell Res) Vol. 24 Issue 2 Pg. 161-76 (Feb 2014) ISSN: 1748-7838 [Electronic] England
• PMID: 24296781 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• CD11a Antigen
• CD40 Antigens
• Fcgr3 protein, mouse
• NF-kappa B
• Receptors, IgG
• CD40 Ligand
• Interferon-gamma
• Protein-Tyrosine Kinases
• Agammaglobulinaemia Tyrosine Kinase
• Btk protein, mouse

Topics

• Agammaglobulinaemia Tyrosine Kinase
• Animals
• B-Lymphocytes (immunology, metabolism)
• Bone Marrow Cells (cytology)
• CD11a Antigen (metabolism)
• CD40 Antigens (metabolism)
• CD40 Ligand (metabolism)
• Cells, Cultured
• Dendritic Cells (cytology, immunology, metabolism)
• Immunity, Innate
• Interferon-gamma (deficiency, genetics, metabolism)
• Listeria monocytogenes (pathogenicity)
• Mice
• Mice, Inbred C57BL
• Mice, Knockout
• NF-kappa B (metabolism)
• Protein-Tyrosine Kinases (deficiency, genetics, metabolism)
• Receptors, IgG (metabolism)