title: New helping friends for B cells.
abstract: Over the past decade, a growing recognition of the importance of neutralizing antibodies in host defense combined with the success of B-cell depletion therapies in treating auto-immune disorders has led to an increased focus on better understanding the pathways underpinning B-cell antibody production. In general, B cells require cognate interaction with T helper cells in the germinal center of lymphoid follicles to generate protective antibodies. However, recent evidence shows that B cells receive additional help from invariant natural killer T cells, dendritic cells, and various granulocytes, including neutrophils, eosinophils, and basophils. These innate immune cells enhance T-cell-dependent antibody responses by delivering B-cell helper signals both in the germinal center and at postgerminal center lymphoid sites such as the bone marrow. In addition to enhancing and complementing the B-cell helper activity of canonical T cells, invariant natural killer T cells, dendritic cells, and granulocytes can deliver T cell-independent B-cell helper signals at the mucosal interface and in the marginal zone of the spleen to initiate rapid innate-like antibody responses. Here, we discuss recent advances in the role of adaptive and innate B-cell helper signals in antibody diversification and production.
authors.affiliation: ICREA, Catalan Institute for Research and Advanced Studies, Barcelona Biomedical Research Park, Barcelona, Spain. acerutti@imim.es
authors.forename: Andrea
authors.initials: A
authors.lastname: Cerutti
authors.forename: Irene
authors.initials: I
authors.lastname: Puga
authors.forename: Montserrat
authors.initials: M
authors.lastname: Cols
mesh_terms: D056704:Adaptive Immunity; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D002450:Cell Communication; D003713:Dendritic Cells / Q000276:immunology; D018858:Germinal Center / Q000276:immunology; D006098:Granulocytes / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate; D008213:Lymphocyte Activation; D008221:Lymphoid Tissue / Q000276:immunology; D055611:Natural Killer T-Cells / Q000276:immunology; D015398:Signal Transduction; D013154:Spleen / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology