Characterization and role of B1 cells in experimental models: murine melanoma and Paracoccidioides brasiliensis infection

• Grant number: 07/51501-9
• Support Opportunities: Research Projects - Thematic Grants
• Start date: September 01, 2007
• End date: August 31, 2010
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: José Daniel Lopes
• Grantee: José Daniel Lopes
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

A large number of reports have been made in order to characterize and determine the origin and function of B-1 cells. At least three B cell subsets, B-1a, B-1b and B-2 (conventional B cells) are present in the mouse periphery. B1 cells express high levels of surface IgM, low levels of B220 and IgD, but not CD23, whereas conventional B-2 cells express high levels of B220 and IgD, CD23 and low levels of IgM. Although B-1 cells bear several features of B Iymphocytes, they also express characteristic surface markers of monocyte-derived macrophages such as low levels of Mac-1. Moreover, a subset designed B-1 a have intermediate levels of CD5 on their surface. However, Mac-1 and CD5 antigens are lost when B-1 cells migrate out of the peritoneal cavity. These cells might play a role on the kinetics and fate of the inflammatory response and on parasite infection. Xid mice, that have impaired production of B-1 lymphocyte, are significantly more resistant to T cruzi, P. brasiliensis (Kipnis, pers commun) and lymphatic filarial parasite infections. These data support the hypothesis that B-1 cells could down-regulate the efficacy of effectors cells, such as macrophages, to eliminate parasites in the inflammatory milieu. Additionally, B-1 cells produce and utilize IL-10 as an autocrine growth factor and this cytokine is an important negative regulator of cell mediated immunity. In this direction, our group demonstrated that B-1 cells can influence effectors functions of macrophages in vitro via IL-10 secretion. The role of these cells in the melanoma metastatic potential was demonstrated in vitro. B16F10 co-cultivated with B1 cells have increased expression of adhesion and protease molecules. Besides that, non-tumorigenic immortalized melanocytes (melan-a) co-cultivated with B1 cells for 72 hours were able to form tumors in mice. Herein we intend to demonstrate the importance of B-1 cells in melanoma and paracoccidioidomycosis, as well as evaluated their role in inflammation, autoimmunity and tolerance. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

XANDER, PATRICIA; NOVAES E BRITO, RONNI ROMULO; PEREZ, ELIZABETH CRISTINA; POZZIBON, JAQUELINE MACIEL; DE SOUZA, CAMILA FERREIRA; PELLEGRINO, RENATA; BERNARDO, VIVIANE; JASIULIONIS, MIRIAM GALVONAS; MARIANO, MARIO; LOPES, JOSE DANIEL. Crosstalk between B16 melanoma cells and B-1 lymphocytes induces global changes in tumor cell gene expression. Immunobiology, v. 218, n. 10, p. 1293-1303, OCT 2013. (07/51501-9)

LOPES, JOSE DANIEL; MARIANO, MARIO. B-1 cell: the precursor of a novel mononuclear phagocyte with immuno-regulatory properties. Anais da Academia Brasileira de Ciências, v. 81, n. 3, p. 489-496, SEP 2009. (07/51501-9, 04/08506-1)

PUGLIESE, LIVIA SOUZA; GONCALVES, THAIS OLIVEIRA; POPI, ANA FLAVIA; MARIANO, MARIO; PESQUERO, JOAO BOSCO; LOPES, JOSE DANIEL. B-1 lymphocytes differentiate into functional osteoclast-like cells. Immunobiology, v. 217, n. 3, p. 336-344, MAR 2012. (07/51501-9)