title: Cross talk between peritoneal macrophages and B-1 cells in vitro.
abstract: B-1 cells constitute a distinct B cell population with unique phenotypic and functional characteristics. They represent the main B cell population found in mouse peritoneal and pleural cavities. The communication between B-1 cells and peritoneal macrophages has been previously studied, and the effect this interaction has on macrophages has been previously described. Using an in vitro co-culture model, herein we demonstrated that peritoneal macrophages were able to increase survival rates and to stimulate proliferation of B-1 cells. IL-6 was also found to be important in B-1 cell survival; recombinant IL-6 increases the percentage of viable B-1 cells in culture. Furthermore, molecules involved in the IL-6 signaling pathway, such as STAT-3 and Bcl-2, were highly expressed in B-1 cells after co-culture with peritoneal macrophages. IL-6-deficient peritoneal macrophages were not able to increase B-1 cell survival, confirming the importance of this cytokine. Altogether, our results indicate a novel mechanism in which peritoneal macrophages are able to regulate the B-1 population via IL-6 secretion.
authors.affiliation: Discipline of Immunology, Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Felipe Garutti
authors.initials: FG
authors.lastname: Thies
authors.forename: Maria Fernanda Lucatelli
authors.initials: MF
authors.lastname: Laurindo
authors.forename: Elizabeth Cristina
authors.initials: EC
authors.lastname: Perez
authors.forename: Ronni Romulo
authors.initials: RR
authors.lastname: Novaes e Brito
authors.forename: Mario
authors.initials: M
authors.lastname: Mariano
authors.forename: Ana Flavia
authors.initials: AF
authors.lastname: Popi
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology*; D015153:Blotting, Western; D005434:Flow Cytometry; D015850:Interleukin-6 / Q000378:metabolism*; D017737:Macrophages, Peritoneal / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D020239:Receptor Cross-Talk / Q000502:physiology*; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D015850:Interleukin-6; D019253:Proto-Oncogene Proteins c-bcl-2; D050796:STAT3 Transcription Factor