Human neutrophil migration and activation by BJcuL, a galactose binding lectin purified from Bothrops jararacussu venom

Selene Elifio-Esposito,Gabriel M Fugii,Carolina Schwartz,Andréa N Moreno,Luciana Fm Zishler,Luiz Claudio Fernandes,Luciane Tomazeli,Patrícia M Stuelp-Campelo,Ana Paula Gimenez

doi:10.1186/1471-2172-12-10

Selene Elifio-Esposito, Gabriel M Fugii + Show 7 more

Open Access

https://doi.org/10.1186/1471-2172-12-10

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Abstract

BackgroundNeutrophil migration to an inflamed site constitutes the first line of the innate immune response against invading microorganisms. Given the crucial role of endogenous lectins in neutrophil mobilization and activation, lectins from exogenous sources have often been considered as putative modulators of leukocyte function. Lectins purified from snake venom have been described as galactoside ligands that induce erythrocyte agglutination and platelet aggregation. This study evaluated human neutrophil migration and activation by C-type lectin BJcuL purified from Bothrops jararacussu venom.ResultsUtilizing fluorescence microscopy, we observed that biotinylated-BJcuL was evenly distributed on the neutrophil surface, selectively inhibited by D-galactose. Lectin was able to induce modification in the neutrophil morphology in a spherical shape for a polarized observed by optical microscopy and exposure to BJcuL in a Boyden chamber assay resulted in cell migration. After 30 minutes of incubation with BJcuL we found enhanced neutrophil functions, such as respiratory burst, zymozan phagocytosis and an increase in lissosomal volume. In addition, BJcuL delays late apoptosis neutrophils.ConclusionThese results demonstrate that BJcuL can be implicated in a wide variety of immunological functions including first-line defense against pathogens, cell trafficking and induction of the innate immune response since lectin was capable of inducing potent neutrophil activation.

Highlights

Neutrophil migration to an inflamed site constitutes the first line of the innate immune response against invading microorganisms
Viperid and elapid snake venoms contain complex mixtures of pharmacologically active molecules, including enzymes and proteins without enzymatic activity, such as C-type lectins. Based on their structural and functional properties snake venom C-type lectins have been classified as true C-type lectins, which contain a carbohydrate recognition domain (CRD) and bind to a specific sugar molecule, and the C-type lectin-like domain proteins (CTLDs) with CRD-related non-carbohydrate-binding domains that do not bind to a sugar moiety [6,7], but act as factor IX/X-binding proteins and those interacting with platelet receptors [8]
Bothrops jararacussu venom lectin (BJcuL) induces polarization of human neutrophils Since neutrophils are polarized when exposed to chemoattractants, we analyzed the capacity of BJcuL to induce polarization of human neutrophils

Summary

Introduction

Neutrophil migration to an inflamed site constitutes the first line of the innate immune response against invading microorganisms. Neutrophil activation leads to directed migration with changes in cell morphology from rounded cells covered with microvilli to elongated ruffled cells [2,3] Neutrophils exert their bactericidal activity at the inflammatory site through recognition and phagocytosis of the infectious agent, generation of toxic oxygen derivatives, and release of microbicidal molecules from their specialized lysosomes and granules [4]. Viperid and elapid snake venoms contain complex mixtures of pharmacologically active molecules, including enzymes and proteins without enzymatic activity, such as C-type lectins. Based on their structural and functional properties snake venom C-type lectins have been classified as true C-type lectins, which contain a carbohydrate recognition domain (CRD) and bind to a specific sugar molecule, and the C-type lectin-like domain proteins (CTLDs) with CRD-related non-carbohydrate-binding domains that do not bind to a sugar moiety [6,7], but act as factor IX/X-binding proteins and those interacting with platelet receptors [8].

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