Leucocyte-derived extracellular trap formation significantly contributes to Haemonchus contortus larval entrapment

• DOI: 10.1186/s13071-015-1219-1
• Publication Date: 2015-11-26T11:50:23Z
• Authors: Tamara Muñoz-Caro; Mario C. Rubio R; Liliana M. R. Silva; Gerd Magdowski; Ulrich Gärtner; Tom N. McNeilly; Anja Taubert; Carlos Hermosilla
• Keywords: Neutrophil Extracellular Traps

Polymorphonuclear neutrophil (PMN) and eosinophil extracellular trap (ETs) formation has recently been described as an important host effector mechanism against invading pathogens. So far, scarce evidence on metazoan-triggered ET published. We here describe for the first time Haemonchus contortus-triggered ETs being released by bovine PMN ovine eosinophils in response to ensheathed exsheathed third stage larvae (L3). The visualization of was achieved SEM analysis. identification classical components performed via fluorescence microscopy effect larval exsheathment parasite integrity evaluated Pico Green®- intensities. under acidic conditions assessed using media different pH ranges. Parasite entrapment microscopically after co-culture L3. inhibition experiments were inhibitors NADPH oxidase, NE MPO. Eosinophil-derived estimated L3 significantly induced PMN-mediated significant through structures rapidly observed 60 min co-culture. Co-localization studies PMN-derived DNA with histones (H3), elastase (NE) myeloperoxidase (MPO) parasite-entrapping confirmed characteristics ETs. diminished oxidase-, NE- MPO-inhibition. Interestingly, forms ETs, i.e. aggregated (aggETs), spread (sprETs) diffused (diffETs) AggETs sprETs firmly ensnared a dependent manner. Significantly stronger aggETs reactions detected upon exposure than ones. Low are present abomasum did not block ETosis led moderate decrease Eosinophil-ETs identified extruding staining. postulate that may limit establishment H. contortus within definitive immobilizing hampering them from migrating into site infection. Consequently, contortus-mediated might have impact outcome disease. Finally, besides PMN-triggered we indications exposure.