Tick saliva protein Evasin-3 modulates chemotaxis by disrupting CXCL8 interactions with glycosaminoglycans and CXCR2

Stepan S. Denisov, Johannes H. Ippel, Alexandra C. A. Heinzmann, Rory R. Koenen, Mudena Ortega-Gomez, Oliver Soehnlein, Tilman M. Hackeng, Ingrid Dijkgraaf*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Chemokines are a group of chemotaxis proteins that regulate cell trafficking and play important roles in immune responses and inflammation. Ticks are blood-sucking parasites that secrete numerous immune-modulatory agents in their saliva to evade host immune responses. Evasin-3 is a small salivary protein that belongs to a class of chemokine-binding proteins isolated from the brown dog tick, Rhipicephalus sanguineus. Evasin-3 has been shown to have a high affinity for chemokines CXCL1 and CXCL8 and to diminish inflammation in mice. In the present study, solution NMR spectroscopy was used to investigate the structure of Evasin-3 and its CXCL8-Evasin-3 complex. Evasin-3 is found to disrupt the glycosaminoglycan-binding site of CXCL8 and inhibit the interaction of CXCL8 with CXCR2. Structural data were used to design two novel CXCL8-binding peptides. The linear tEv3 17-56 and cyclic tcEv3 16-56 dPG Evasin-3 variants were chemically synthesized by solid-phase peptide synthesis. The affinity of these newly synthesized variants to CXCL8 was measured by surface plasmon resonance biosensor analysis. The K-d values of tEv3 17-56 and tcEv3 16-56 dPG were 27 and 13 nm, respectively. Both compounds effectively inhibited CXCL8-induced migration of polymorphonuclear neutrophils. The present results suggest utility of synthetic Evasin-3 variants as scaffolds for designing and fine-tuning new chemokine-binding agents that suppress immune responses and inflammation.

Original languageEnglish
Pages (from-to)12370-12379
Number of pages10
JournalJournal of Biological Chemistry
Volume294
Issue number33
DOIs
Publication statusPublished - 16 Aug 2019

Keywords

  • chemokine
  • peptide chemical synthesis
  • nuclear magnetic resonance (NMR)
  • protein structure
  • protein-protein interaction
  • C-X-C motif chemokine ligand (CXCL)
  • CHEMOKINE-BINDING-PROTEINS
  • CYSTINE KNOT
  • WEB SERVER
  • MONOCLONAL-ANTIBODY
  • RECEPTOR CXCR1
  • XPLOR-NIH
  • INTERLEUKIN-8
  • RECOGNITION
  • SELECTIVITY
  • STABILITY

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