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Human monocytes/macrophages are a target of Neisseria meningitidis Adhesin A (NadA)
Author(s) -
Franzoso Susanna,
Mazzon Cristina,
Sztukowska Maryta,
Cecchini Paola,
Kasic Tihana,
Capecchi Barbara,
Tavano Regina,
Papini Emanuele
Publication year - 2008
Publication title -
journal of leukocyte biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.819
H-Index - 191
eISSN - 1938-3673
pISSN - 0741-5400
DOI - 10.1189/jlb.1207810
Subject(s) - bacterial adhesin , neisseria meningitidis , biology , monocyte , microbiology and biotechnology , tumor necrosis factor alpha , macrophage , secretion , phagocytosis , immunology , fimbria , escherichia coli , in vitro , gene , bacteria , biochemistry , genetics
Specific surface proteins of Neisseria meningitidis have been proposed to stimulate leukocytes during tissue invasion and septic shock. In this study, we demonstrate that the adhesin N. meningitidis Adhesin A (NadA) involved in the colonization of the respiratory epithelium by hypervirulent N. meningitidis B strains also binds to and activates human monocytes/macrophages. Expression of NadA on the surface on Escherichia coli does not increase bacterial‐monocyte association, but a NadA‐positive strain induced a significantly higher amount of TNF‐α and IL‐8 compared with the parental NadA‐negative strain, suggesting that NadA has an intrinsic stimulatory action on these cells. Consistently, highly pure, soluble NadA Δ351–405 , a proposed component of an antimeningococcal vaccine, efficiently stimulates monocytes/macrophages to secrete a selected pattern of cytokines and chemotactic factors characterized by high levels of IL‐8, IL‐6, MCP‐1, and MIP‐1α and low levels of the main vasoactive mediators TNF‐α and IL‐1. NadA Δ351–405 also inhibited monocyte apoptosis and determined its differentiation into a macrophage‐like phenotype.