Modulation of proliferation, differentiation and cytokine secretion of murine B-1b cells by proteins of the extracellular matrix

At least three B cell subsets, B-1a (Ly-1B), B-1b and B-2, are present in the mouse periphery. B-1a and B1-b cells represent a small population in the adult spleen and are abundant in the peritonial and pleural cavities. It has been demonstrated in our laboratory that B-1b cells spontaneously proliferated in stationary cultures of adherent peritonial cells. Further, that these cells migrate to a non-specific inflammatory focus. Based on these findings, it was investigated whether components of the extracellular matrix (ECM) might selectively influence the adherence, proliferation and cytokine production of these cells in vitro. Results showed that collagen induced a higher level of B-1b cells differentiation into adhrent phagocytic cells. It was observed that only fibronectin induced higher level of proliferation than other matrix components. the analysis of cytokine production has shown that the presence of laminin stimulated B-1b cells led to high levels of IL-10 production and fibronectin and collagen induced the production of high levels of TNF-alpha. the combination of fibronectin, collagen and laminin induced higher levels of IL-10. These results demonstrate that differentiation, proliferation and cytokine production by B-1b cells are markedly influenced by ECM components. (C) 2002 Elsevier Science B.V. All rights reserved.Universidade Federal de São Paulo, Disciplina Imunol, Dept Microbiol Imunol & Parasitol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Anal Clin & Toxicol, Fac Ciencias Farmaceut, São Paulo, BrazilUniversidade Federal de São Paulo, Disciplina Imunol, Dept Microbiol Imunol & Parasitol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Anal Clin & Toxicol, Fac Ciencias Farmaceut, São Paulo, BrazilWeb of Scienc