LPS-Induced Galectin-3 Oligomerization Results in Enhancement of Neutrophil Activation

Autor(es)

Fermino, Marise Lopes ^{[1, 2]} ; Polli, Claudia Danella ^{[1, 3]} ; Toledo, Karina Alves ^{[1, 2, 4]} ; Liu, Fu-Tong ^[5] ; Hsu, Dan K. ^[5] ; Roque-Barreira, Maria Cristina ^[2] ; Pereira-da-Silva, Gabriela ^[6] ; Bernardes, Emerson Soares ^[7] ; Halbwachs-Mecarelli, Lise ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Paris 05, Paris - France

^[2] Univ Sao Paulo, Fac Med, Dept Cellular & Mol Biol & Pathogen Bioagents, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Fac Med, Program Basic & Appl Immunol, Sao Paulo - Brazil

^[4] Univ Sao Paulo, Dept Biol Sci, Sao Paulo - Brazil

^[5] Univ Calif Davis, Sch Med, Dept Dermatol, Sacramento, CA 95817 - USA

^[6] Univ Sao Paulo, Ribeirao Preto Coll Nursing, Sao Paulo - Brazil

^[7] Univ Porto, Inst Mol Pathol & Immunol, P-4100 Oporto - Portugal

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 6, n. 10, p. e26004, 2011.
• Citações Web of Science: 41

Resumo

Galectin-3 (Gal 3) is a glycan-binding protein that can be secreted by activated macrophages and mast cells at inflammation sites and plays an important role in inflammatory diseases caused by Bacteria and their products, such as lipopolysaccharides (LPS). Although it is well established that Gal 3 can interact with LPS, the pathophysiological importance of LPS/Gal 3 interactions is not fully understood. Data presented herein demonstrate for the first time that the interaction of Gal 3, either via its carbohydrate binding C-terminal domain or via its N-terminal part, with LPS from different bacterial strains, enhances the LPS-mediated neutrophil activation in vitro. Gal 3 allowed low LPS concentrations (1 mu g/mL without serum, 1 ng/mL with serum) to upregulate CD11b expression and reactive oxygen species (ROS) generation on human neutrophils in vitro and drastically enhanced the binding efficiency of LPS to the neutrophil surface. These effects required LPS preincubation with Gal 3, before neutrophil stimulation and involved specific Gal 3/LPS interaction. A C-terminal Gal-3 fragment, which retains the lectin domain but lacks the N-terminal part, was still able to bind both to Escherichia coli LPS and to neutrophils, but had lost the ability to enhance neutrophil response to LPS. This result emphasizes the importance of an N-terminus-mediated Gal 3 oligomerization induced by its interaction with LPS. Finally we demonstrated that Balb/C mice were more susceptible to LPS-mediated shock when LPS was pretreated with Gal 3. Altogether, these results suggest that multimeric interactions between Gal 3 oligomers and LPS potentiate its proinflammatory effects on neutrophils. (AU)

• Processo FAPESP: 06/60757-4 - Participação da galectina-3 na modulação das funções de células T reguladoras (T CD4+CD25+)- a infecção por Leishmania major como modelo
• Beneficiário: Marise Lopes Fermino
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto