Activation of the neutrophil nicotinamide adenine dinucleotide phosphate oxidase by galectin-1.

• Galectins are a group of lactose-binding proteins widely distributed in nature. Twelve mammalian galectins have so far been identified, but their functions are to a large extent unknown. In this work we study galectin-1 in its interaction with human neutrophils, with regard to both cell surface binding and activation of the superoxide-producing NADPH-oxidase. We show that galectin-1 is able to activate the neutrophil NADPH-oxidase, provided that the cells have been primed by extravasation from the blood into the tissue, an activation pattern that is similar to that of galectin-3. Using in vitro priming protocols, the galectin-1 responsiveness was found to correlate to granule mobilization and galectin-1 binding to the cells, suggesting the presence of granule-localized receptors that are up-regulated to the cell surface upon priming. By galectin-1 overlay of fractionated neutrophils we identified potential galectin-1 receptor candidates localized in the membranes of the secretory vesicle and gelatinase granules. The binding of galectin-1 and galectin-3 to neutrophil proteins was compared, as were the dose dependencies for activation by the two lectins. The results suggest that, although similarities are found between the two galectins, they appear to activate the NADPH-oxidase using different receptors. In conclusion, galectin-1 appears to have proinflammatory functions, mediated through activation of the neutrophil respiratory burst.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Immunologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Immunology in the medical area (hsv//eng)

Keyword

Adjuvants

Immunologic

blood

metabolism

physiology

Antigens

Differentiation

metabolism

Carrier Proteins

metabolism

Cell Degranulation

immunology

Cell Movement

immunology

Cytoplasmic Granules

enzymology

immunology

metabolism

Dose-Response Relationship

Immunologic

Enzyme Activation

immunology

Exudates and Transudates

cytology

enzymology

immunology

Galectin 1

Galectin 3

Hemagglutinins

blood

metabolism

physiology

Humans

NADPH Oxidase

blood

metabolism

Neutrophil Activation

immunology

Neutrophils

enzymology

metabolism

Protein Binding

immunology

Receptors

Mitogen

metabolism

Subcellular Fractions

immunology

metabolism

Publication and Content Type

ref (subject category)

art (subject category)