title: With a little help from their friends: interleukin-21, T cells, and B cells.
abstract: T follicular cells help B cells generate high-affinity antibodies. Two papers in this issue of Immunity (Nurieva et al., 2008, and Vogelzang et al., 2008) have identified a role for interleukin-21 in the development of these specialized cells and highlight questions about how this dedicated population is generated.
authors.affiliation: Department of Pathobiology, University of Pennsylvania, School of Veterinary Medicine, Room 313, Hill Pavillion, 380 South University Avenue, Philadelphia, PA 19104-4539, USA.
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Silver
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Hunter
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D018858:Germinal Center / Q000166:cytology / Q000276:immunology; D007378:Interleukins / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D008211:Lymphocyte Cooperation / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D000098546:Interleukin-21
chemical_list: D007378:Interleukins; D000098546:Interleukin-21