title: A Trypanosoma cruzi antigen signals CD11b+ cells to secrete cytokines that promote polyclonal B cell proliferation and differentiation into antibody-secreting cells.
abstract: Microbial-induced polyclonal activation of B cells is a common event in several forms of infections, and is believed to play a crucial role both for enhancing the production of specific antibodies and for maintenance of B cell memory. Therefore, a major challenge in biomedical research is the identification of pathogen-derived products capable of rapidly mounting B cell expansion and differentiation. Here we report that glutamate dehydrogenase (GDH) stimulates polyclonal proliferation and differentiation of naive B cells. This stimulation was found to be T cell independent, but to absolutely require CD11b(+) cells. Moreover, we demonstrate that stimulation of CD11b(+) cells by GDH leads to the production of IL-6, IL-10 and B cell-activating factor (BAFF), all of which combine to powerfully induce B cell expansion. Importantly, IL-6 and IL-10 further drive B cell terminal differentiation into plasma cells by up-regulating critical transcription factors and immunoglobulin secretion. Our data provide the first evidence that a protozoan antigen can induce BAFF production by accessory cells, which in concert with other cytokines trigger polyclonal B cell activation.
authors: Department of Clinical Biochemistry, Faculty of Chemical Science, National University of Córdoba, Argentina.
authors: Carolina L
authors: CL
authors: Montes
authors: Eva V
authors: EV
authors: Acosta-Rodríguez
authors: Juan
authors: J
authors: Mucci
authors: Elina I
authors: EI
authors: Zuniga
authors: Oscar
authors: O
authors: Campetella
authors: Adriana
authors: A
authors: Gruppi