Ticks are important vectors of serious human and animal disease-causing organisms, but their innate immunity can fight invading pathogens and may have the ability to reduce or block transmission to mammalian hosts. Lectins, sugar-binding proteins, can distinguish between self and non-self-oligosaccharide motifs on pathogen surfaces. Although tick hemolymph possesses strong lectin activity, and several lectins have already been isolated and characterized, little is known about the implementation of these molecules in tick immunity. Here, we have described and functionally characterized fibrinogen-related protein (FReP) lectins in Ixodes ticks. We have shown that the FReP family contains at least 27 genes (ixoderins, ixo) that could, based on phylogenetic and expression analyses, be divided into three groups with differing degrees of expansion. By using RNA interference-mediated gene silencing (RNAi) we demonstrated that IXO-A was the main lectin in tick hemolymph. Further, we found that ixoderins were important for phagocytosis of Gram-negative bacteria and yeasts by tick hemocytes and that their expression was upregulated upon injection of microbes, wounding, or after blood feeding. However, although the tick hemocytes could swiftly phagocytose Borrelia afzelii spirochetes, their transmission and burst of infection in mice was not altered. Our results demonstrate that tick ixoderins are crucial immune proteins that work as opsonins in the tick hemolymph, targeting microbes for phagocytosis or lysis.

Biology Centre Institute of Parasitology Czech Academy of Sciences Ceske Budejovice Czechia

Faculty of Science University of South Bohemia Ceske Budejovice Czechia

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Burešová V., Franta Z., Kopáček P. (2006). A comparison of Chryseobacterium indologenes pathogenicity to the soft tick Ornithodoros moubata and hard tick Ixodes ricinus. J. Invertebr. Pathol. 93, 96–104. 10.1016/j.jip.2006.05.006 PubMed DOI

Buresova V., Hajdusek O., Franta Z., Loosova G., Grunclova L., Levashina E. A., et al. . (2011). Functional genomics of tick thioester-containing proteins reveal the ancient origin of the complement system. J. Innate Immun. 3, 623–630. 10.1159/000328851 PubMed DOI

Burgdorfer W. (1984). Discovery of the lyme disease spirochete and its relation to tick vectors. Yale J. Biol. Med. 57, 515–520. PubMed PMC

Cerenius L., Soderhall K. (2013). Variable immune molecules in invertebrates. J. Exp. Biol. 216, 4313–4319. 10.1242/jeb.085191 PubMed DOI

DeFranco A., Locksley R. M., Robertson M. (2007). Immunity: The Immune Response in Infectious and Inflammatory Disease. London: New Science Press.

de Taeye S. W., Kreuk L., van Dam A. P., Hovius J. W., Schuijt T. J. (2013). Complement evasion by Borrelia burgdorferi: it takes three to tango. Trends Parasitol. 29, 119–128. 10.1016/j.pt.2012.12.001 PubMed DOI

Dong Y., Aguilar R., Xi Z., Warr E., Mongin E., Dimopoulos G. (2006). Anopheles gambiae immune responses to human and rodent Plasmodium parasite species. PLoS Pathog. 2:e52. 10.1371/journal.ppat.0020052 PubMed DOI PMC

Dong Y., Dimopoulos G. (2009). Anopheles fibrinogen-related proteins provide expanded pattern recognition capacity against bacteria and malaria parasites. J. Biol. Chem. 284, 9835–9844. 10.1074/jbc.M807084200 PubMed DOI PMC

Dunham-Ems S. M., Caimano M. J., Pal U., Wolgemuth C. W., Eggers C. H., Balic A., et al. . (2009). Live imaging reveals a biphasic mode of dissemination of Borrelia burgdorferi within ticks. J. Clin. Invest. 119, 3652–3665. 10.1172/JCI39401 PubMed DOI PMC

Dusbábek F. (1996). Nymphal sexual dimorphism in the sheep tick Ixodes ricinus (Acari: Ixodidae). Folia Parasitol. 43, 75–79. PubMed

Endo Y., Matsushita M., Fujita T. (2011). The role of ficolins in the lectin pathway of innate immunity. Int. J. Biochem. Cell Biol. 43, 705–712. 10.1016/j.biocel.2011.02.003 PubMed DOI

Gokudan S., Muta T., Tsuda R., Koori K., Kawahara T., Seki N., et al. . (1999). Horseshoe crab acetyl group-recognizing lectins involved in innate immunity are structurally related to fibrinogen. Proc. Natl. Acad. Sci. U.S.A. 96, 10086–10091. 10.1073/pnas.96.18.10086 PubMed DOI PMC

Grubhoffer L., Kovár V., Rudenko N. (2004). Tick lectins: structural and functional properties. Parasitology 129, S113–S125. 10.1017/S0031182004004858 PubMed DOI

Hajdušek O., Síma R., Ayllón N., Jalovecká M., Perner J., de la Fuente J., et al. . (2013). Interaction of the tick immune system with transmitted pathogens. Front. Cell. Infect. Microbiol. 3:26. 10.3389/fcimb.2013.00026 PubMed DOI PMC

Hajdusek O., Sojka D., Kopacek P., Buresova V., Franta Z., Sauman I., et al. (2009). Knockdown of proteins involved in iron metabolism limits tick reproduction and development. Proc. Natl. Acad. Sci. U.S.A. 106, 1033–1038. 10.1073/pnas.0807961106 PubMed DOI PMC

Hanington P. C., Zhang S. M. (2011). The primary role of fibrinogen-related proteins in invertebrates is defense, not coagulation. J. Innate Immun. 3, 17–27. 10.1159/000321882 PubMed DOI PMC

Iwanaga S. (2002). The molecular basis of innate immunity in the horseshoe crab. Curr. Opin. Immunol. 14, 87–95. 10.1016/S0952-7915(01)00302-8 PubMed DOI

Jongejan F., Uilenberg G. (2004). The global importance of ticks. Parasitology 129, 3–14. 10.1017/S0031182004005967 PubMed DOI

Kovár V., Kopáček P., Grubhoffer L. (2000). Isolation and characterization of Dorin M, a lectin from plasma of the soft tick Ornithodoros moubata. Insect Biochem. Mol. Biol. 30, 195–205. 10.1016/S0965-1748(99)00107-1 PubMed DOI

Le Saux A., Ng P. M. L., Koh J. J. Y., Low D. H. P., Leong G. E. L., Ho B., et al. . (2008). The macromolecular assembly of pathogen-recognition receptors is impelled by serine proteases, via their complement control protein modules. J. Mol. Biol. 377, 902–913. 10.1016/j.jmb.2008.01.045 PubMed DOI

Levashina E. A., Moita L. F., Blandin S., Vriend G., Lagueux M., Kafatos F. C. (2001). Conserved role of a complement-like protein in phagocytosis revealed by dsRNA knockout in cultured cells of the mosquito, Anopheles gambiae. Cell 104, 709–718. 10.1016/S0092-8674(01)00267-7 PubMed DOI

Ng P. M. L., Le Saux A., Lee C. M., Tan N. S., Lu J., Thiel S., et al. . (2007). C-reactive protein collaborates with plasma lectins to boost immune response against bacteria. EMBO J. 26, 3431–3440. 10.1038/sj.emboj.7601762 PubMed DOI PMC

Obonyo M., Munderloh U. G., Fingerle V., Wilske B., Kurtti T. J. (1999). Borrelia burgdorferi in tick cell culture modulates expression of outer surface proteins A and C in response to temperature. J. Clin. Microbiol. 37, 2137–2141. PubMed PMC

Ohnishi J., Piesman J., de Silva A. M. (2001). Antigenic and genetic heterogeneity of Borrelia burgdorferi populations transmitted by ticks. Proc. Natl. Acad. Sci. U.S.A. 98, 670–675. 10.1073/pnas.98.2.670 PubMed DOI PMC

Palmer W. J., Jiggins F. M. (2015). Comparative genomics reveals the origins and diversity of arthropod immune systems. Mol. Biol. Evol. 32, 2111–2129. 10.1093/molbev/msv093 PubMed DOI PMC

Pfaffl M. W. (2001). A new mathematical model for relative quantification in real-time RT-PCR. Nucleic Acids Res. 29:e45. 10.1093/nar/29.9.e45 PubMed DOI PMC

Ramamoorthi N., Narasimhan S., Pal U., Bao F., Yang X. F., Fish D., et al. . (2005). The lyme disease agent exploits a tick protein to infect the mammalian host. Nature 436, 573–577. 10.1038/nature03812 PubMed DOI PMC

Rego R. O. M., Hajdušek O., Kovár V., Kopáček P., Grubhoffer L., Hypša V. (2005). Molecular cloning and comparative analysis of fibrinogen-related proteins from the soft tick Ornithodoros moubata and the hard tick Ixodes ricinus. Insect Biochem. Mol. Biol. 35, 991–1004. 10.1016/j.ibmb.2005.04.001 PubMed DOI

Rego R. O. M., Kovár V., Kopáček P., Weise C., Man P., Šauman I., et al. . (2006). The tick plasma lectin, Dorin M, is a fibrinogen-related molecule. Insect Biochem. Mol. Biol. 36, 291–299. 10.1016/j.ibmb.2006.01.008 PubMed DOI

Ricklin D., Hajishengallis G., Yang K., Lambris J. D. (2010). Complement: a key system for immune surveillance and homeostasis. Nat. Immunol. 11, 785–797. 10.1038/ni.1923 PubMed DOI PMC

Rittig M. G., Kuhn K. H., Dechant C. A., Gauckler A., Modolell M., Ricciardi-Castagnoli P., et al. . (1996). Phagocytes from both vertebrate and invertebrate species use “coiling” phagocytosis. Dev. Comp. Immunol. 20, 393–406. 10.1016/S0145-305X(96)00023-7 PubMed DOI

Schuijt T. J., Coumou J., Narasimhan S., Dai J., Deponte K., Wouters D., et al. . (2011a). A tick mannose-binding lectin inhibitor interferes with the vertebrate complement cascade to enhance transmission of the Lyme disease agent. Cell Host Microbe 10, 136–146. 10.1016/j.chom.2011.06.010 PubMed DOI PMC

Schuijt T. J., Narasimhan S., Daffre S., DePonte K., Hovius J. W. R., van't Veer C., et al. . (2011b). Identification and characterization of Ixodes scapularis antigens that elicit tick immunity using yeast surface display. PLoS ONE 6:e15926. 10.1371/journal.pone.0015926 PubMed DOI PMC

Simser J. A., Mulenga A., Macaluso K. R., Azad A. F. (2004). An immune responsive factor D-like serine proteinase homologue identified from the American dog tick, Dermacentor variabilis. Insect Mol. Biol. 13, 25–35. 10.1111/j.1365-2583.2004.00455.x PubMed DOI

Sonenshine D. E., Macaluso K. R. (2017). Microbial invasion vs. tick immune regulation. Front. Cell. Infect. Microbiol. 7:390. 10.3389/fcimb.2017.00390 PubMed DOI PMC

Štepánová-Tresová G., Kopecký J., Kuthejlová M. (2000). Identification of Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii in Ixodes ricinus ticks from Southern Bohemia using monoclonal antibodies. Zentralblatt für Bakteriol. 289, 797–806. 10.1016/S0934-8840(00)80005-5 PubMed DOI

Sterba J., Dupejova J., Fiser M., Vancova M., Grubhoffer L. (2011). Fibrinogen-related proteins in ixodid ticks. Parasit. Vectors 4:127. 10.1186/1756-3305-4-127 PubMed DOI PMC

Tagawa K., Yoshihara T., Shibata T., Kitazaki K., Endo Y., Fujita T., et al. (2012). Microbe-specific C3b deposition in the horseshoe crab complement system in a C2/factor B-dependent or -independent manner. PLoS ONE 7:e36783 10.1371/journal.pone.0036783 PubMed DOI PMC

Urbanova V., Hajdušek O., Hönig Mondeková H., Šíma R., Kopáček P. (2017). Tick thioester-containing proteins and phagocytosis do not affect transmission of Borrelia afzelii from the competent vector Ixodes ricinus. Front. Cell. Infect. Microbiol. 7:73 10.3389/fcimb.2017.00073 PubMed DOI PMC

Urbanova V., Šíma R., Šauman I., Hajdušek O., Kopáček P. (2015). Thioester-containing proteins of the tick Ixodes ricinus: gene expression, response to microbial challenge and their role in phagocytosis of the yeast Candida albicans. Dev. Comp. Immunol. 48, 55–64. 10.1016/j.dci.2014.09.004 PubMed DOI

Urbanova V., Hajdusek O., Sima R., Franta Z., Honig-Mondekova H., Grunclova L., et al. . (2018). IrC2/Bf - a yeast and Borrelia responsive component of the complement system from the hard tick Ixodes ricinus. Dev. Comp. Immunol. 79, 86–94. 10.1016/j.dci.2017.10.012 PubMed DOI

Urbanova V., Hartmann D., Grunclova L., Sima R., Flemming T., Hajdusek O., et al. . (2014). IrFC-an Ixodes ricinus injury-responsive molecule related to Limulus factor C. Dev. Comp. Immunol. 46, 439–447. 10.1016/j.dci.2014.05.016 PubMed DOI

Zhu Y., Ng P. M. L., Wang L., Ho B., Ding J. L. (2006). Diversity in lectins enables immune recognition and differentiation of wide spectrum of pathogens. Int. Immunol. 18, 1671–1680. 10.1093/intimm/dxl101 PubMed DOI

Zhu Y., Thangamani S., Ho B., Ding J. L. (2005). The ancient origin of the complement system. EMBO J. 24, 382–394. 10.1038/sj.emboj.7600533 PubMed DOI PMC

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