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Alarmin S100A11 initiates a chemokine response to the human pathogen Toxoplasma gondii


Toxoplasma gondii is a common protozoan parasite that infects up to one third of the world’s population. Notably, very little is known about innate immune sensing mechanisms for this obligate intracellular parasite by human cells. Here, by applying an unbiased biochemical screening approach, we show that human monocytes recognized the presence of T. gondii infection by detecting the alarmin S100A11 protein, which is released from parasite-infected cells via caspase-1-dependent mechanisms. S100A11 induced a potent chemokine response to T. gondii by engaging its receptor RAGE, and regulated monocyte recruitment in vivo by inducing expression of the chemokine CCL2. Our experiments reveal a sensing system for T. gondii by human cells that is based on the detection of infection-mediated release of S100A11 and RAGE-dependent induction of CCL2, a crucial chemokine required for host resistance to the parasite.

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Fig. 1: Transcriptome analysis identifies CCL2 as a signature response to T. gondii infection.
Fig. 2: Soluble mediator elicits CCL2 production in response to T. gondii infection.
Fig. 3: Biochemical isolation of S100A11 as a CCL2-inducing molecule.
Fig. 4: Role of RAGE in S100A11-induced CCL2.
Fig. 5: Role of caspase-1 in S100A11 release.
Fig. 6: S100A11 regulates monocyte recruitment in vivo.

Data availability

The materials, data, and any associated protocols that support the findings of this study are available from the authors upon reasonable request. All RNA-seq data generated in this study have been deposited in the Gene Expression Omnibus (GEO) under accession code GSE119835.


  1. Iwasaki, A. & Medzhitov, R. Control of adaptive immunity by the innate immune system. Nat. Immunol. 16, 343–353 (2015).

    CAS  Article  Google Scholar 

  2. Man, S. M., Karki, R. & Kanneganti, T. D. Molecular mechanisms and functions of pyroptosis, inflammatory caspases and inflammasomes in infectious diseases. Immunol. Rev. 277, 61–75 (2017).

    CAS  Article  Google Scholar 

  3. Kawai, T. & Akira, S. The role of pattern-recognition receptors in innate immunity: update on Toll-like receptors. Nat. Immunol. 11, 373–384 (2010).

    CAS  Article  Google Scholar 

  4. Yarovinsky, F. Innate immunity to Toxoplasma gondii infection. Nat. Rev. Immunol. 14, 109–121 (2014).

    CAS  Article  Google Scholar 

  5. Pifer, R. & Yarovinsky, F. Innate responses to Toxoplasma gondii in mice and humans. Trends. Parasitol. 27, 388–393 (2011).

    CAS  Article  Google Scholar 

  6. Yarovinsky, F. et al. TLR11 activation of dendritic cells by a protozoan profilin-like protein. Science 308, 1626–1629 (2005).

    CAS  Article  Google Scholar 

  7. Plattner, F. et al. Toxoplasma profilin is essential for host cell invasion and TLR11-dependent induction of an interleukin-12 response. Cell Host Microbe 3, 77–87 (2008).

    CAS  Article  Google Scholar 

  8. Raetz, M. et al. Cooperation of TLR12 and TLR11 in the IRF8-dependent IL-12 response to Toxoplasma gondii profilin. J. Immunol. 191, 4818–4827 (2013).

    CAS  Article  Google Scholar 

  9. Koblansky, A. A. et al. Recognition of profilin by Toll-like receptor 12 is critical for host resistance to Toxoplasma gondii. Immunity 38, 119–130 (2013).

    CAS  Article  Google Scholar 

  10. Andrade, W. A. et al. Combined action of nucleic acid-sensing Toll-like receptors and TLR11/TLR12 heterodimers imparts resistance to Toxoplasma gondii in mice. Cell Host Microbe 13, 42–53 (2013).

    CAS  Article  Google Scholar 

  11. Neal, L. M. & Knoll, L. J. Toxoplasma gondii profilin promotes recruitment of Ly6Chi CCR2+ inflammatory monocytes that can confer resistance to bacterial infection. PLoS Pathog. 10, e1004203 (2014).

  12. Dupont, C. D., Christian, D. A. & Hunter, C. A. Immune response and immunopathology during toxoplasmosis. Semin. Immunopathol. 34, 793–813 (2012).

    CAS  Article  Google Scholar 

  13. Roach, J. C. et al. The evolution of vertebrate Toll-like receptors. Proc. Natl Acad. Sci. USA 102, 9577–9582 (2005).

    CAS  Article  Google Scholar 

  14. Muller, U. B. & Howard, J. C. The impact of Toxoplasma gondii on the mammalian genome. Curr. Opin. Microbiol. 32, 19–25 (2016).

    Article  Google Scholar 

  15. Debierre-Grockiego, F. et al. Activation of TLR2 and TLR4 by glycosylphosphatidylinositols derived from Toxoplasma gondii. J. Immunol. 179, 1129–1137 (2007).

    CAS  Article  Google Scholar 

  16. Ewald, S. E., Chavarria-Smith, J. & Boothroyd, J. C. NLRP1 is an inflammasome sensor for Toxoplasma gondii. Infect. Immun. 82, 460–468 (2014).

    Article  Google Scholar 

  17. Clay, G. M., Sutterwala, F. S. & Wilson, M. E. NLR proteins and parasitic disease. Immunol. Res. 59, 142–152 (2014).

    CAS  Article  Google Scholar 

  18. Black, M. W. & Boothroyd, J. C. Lytic cycle of Toxoplasma gondii. Microbiol. Mol. Biol. Rev. 64, 607–623 (2000).

    CAS  Article  Google Scholar 

  19. Denkers, E. Y., Schneider, A. G., Cohen, S. B. & Butcher, B. A. Phagocyte responses to protozoan infection and how Toxoplasma gondii meets the challenge. PLoS Pathog. 8, e1002794 (2012).

    CAS  Article  Google Scholar 

  20. Hakimi, M. A., Olias, P. & Sibley, L. D. Toxoplasma effectors targeting host signaling and transcription. Clin. Microbiol. Rev. 30, 615–645 (2017).

    Article  Google Scholar 

  21. Gay, G. et al. Toxoplasma gondii TgIST co-opts host chromatin repressors dampening STAT1-dependent gene regulation and IFN-γ-mediated host defenses. J. Exp. Med. 213, 1779–1798 (2016).

    CAS  Article  Google Scholar 

  22. Olias, P., Etheridge, R. D., Zhang, Y., Holtzman, M. J. & Sibley, L. D. Toxoplasma effector recruits the Mi-2/NuRD complex to repress STAT1 transcription and block IFN-γ-dependent gene expression. Cell Host Microbe 20, 72–82 (2016).

    CAS  Article  Google Scholar 

  23. Naor, A. et al. MYR1-dependent effectors are the major drivers of a host cell’s early response to Toxoplasma, including counteracting MYR1-independent effects. MBio 9, e02401-17 (2018).

  24. Koshy, A. A. et al. Toxoplasma co-opts host cells it does not invade. PLoS Pathog. 8, e1002825 (2012).

    CAS  Article  Google Scholar 

  25. Tosh, K. W. et al. The IL-12 response of primary human dendritic cells and monocytes to Toxoplasma gondii is stimulated by phagocytosis of live parasites rather than host cell invasion. J. Immunol. 196, 345–356 (2016).

    CAS  Article  Google Scholar 

  26. Christian, D. A. et al. Use of transgenic parasites and host reporters to dissect events that promote interleukin-12 production during toxoplasmosis. Infect. Immun. 82, 4056–4067 (2014).

    Article  Google Scholar 

  27. Melo, M. B., Jensen, K. D. & Saeij, J. P. Toxoplasma gondii effectors are master regulators of the inflammatory response. Trends. Parasitol. 27, 487–495 (2011).

    CAS  Article  Google Scholar 

  28. Donato, R. S100: a multigenic family of calcium-modulated proteins of the EF-hand type with intracellular and extracellular functional roles. Int. J. Biochem. Cell. Biol. 33, 637–668 (2001).

    CAS  Article  Google Scholar 

  29. Donato, R. et al. Functions of S100 proteins. Curr. Mol. Med. 13, 24–57 (2013).

    CAS  Article  Google Scholar 

  30. Ulas, T. et al. S100-alarmin-induced innate immune programming protects newborn infants from sepsis. Nat. Immunol. 18, 622–632 (2017).

    CAS  Article  Google Scholar 

  31. Gross, S. R., Sin, C. G., Barraclough, R. & Rudland, P. S. Joining S100 proteins and migration: for better or for worse, in sickness and in health. Cell. Mol. Life Sci. 71, 1551–1579 (2014).

    CAS  Article  Google Scholar 

  32. Kierdorf, K. & Fritz, G. RAGE regulation and signaling in inflammation and beyond. J. Leukoc. Biol. 94, 55–68 (2013).

    CAS  Article  Google Scholar 

  33. Leclerc, E., Fritz, G., Vetter, S. W. & Heizmann, C. W. Binding of S100 proteins to RAGE: an update. Biochim. Biophys. Acta 1793, 993–1007 (2009).

    CAS  Article  Google Scholar 

  34. Koch, M. et al. Structural basis for ligand recognition and activation of RAGE. Structure 18, 1342–1352 (2010).

    CAS  Article  Google Scholar 

  35. Penumutchu, S. R., Chou, R. H. & Yu, C. Structural insights into calcium-bound S100P and the V domain of the RAGE complex. PLoS One 9, e103947 (2014).

    Article  Google Scholar 

  36. Hori, M. et al. Mycalolide-B, a novel and specific inhibitor of actomyosin ATPase isolated from marine sponge. FEBS Lett. 322, 151–154 (1993).

    CAS  Article  Google Scholar 

  37. Lavine, M. D. & Arrizabalaga, G. Exit from host cells by the pathogenic parasite Toxoplasma gondii does not require motility. Eukaryot. Cell 7, 131–140 (2008).

    CAS  Article  Google Scholar 

  38. Dunay, I. R. et al. Gr1(+) inflammatory monocytes are required for mucosal resistance to the pathogen Toxoplasma gondii. Immunity 29, 306–317 (2008).

    CAS  Article  Google Scholar 

  39. Serbina, N. V., Jia, T., Hohl, T. M. & Pamer, E. G. Monocyte-mediated defense against microbial pathogens. Annu. Rev. Immunol. 26, 421–452 (2008).

    CAS  Article  Google Scholar 

  40. Shi, C. & Pamer, E. G. Monocyte recruitment during infection and inflammation. Nat. Rev. Immunol. 11, 762–774 (2011).

    CAS  Article  Google Scholar 

  41. Kim, Y. G. et al. The Nod2 sensor promotes intestinal pathogen eradication via the chemokine CCL2-dependent recruitment of inflammatory monocytes. Immunity 34, 769–780 (2011).

    CAS  Article  Google Scholar 

  42. Gov, L., Schneider, C. A., Lima, T. S., Pandori, W. & Lodoen, M. B. NLRP3 and potassium efflux drive rapid IL-1β release from primary human monocytes during Toxoplasma gondii infection. J. Immunol. 199, 2855–2864 (2017).

    CAS  Article  Google Scholar 

  43. Robben, P. M., LaRegina, M., Kuziel, W. A. & Sibley, L. D. Recruitment of Gr-1+ monocytes is essential for control of acute toxoplasmosis. J. Exp. Med. 201, 1761–1769 (2005).

    CAS  Article  Google Scholar 

  44. Pifer, R., Benson, A., Sturge, C. R. & Yarovinsky, F. UNC93B1 is essential for TLR11 activation and IL-12-dependent host resistance to Toxoplasma gondii. J. Biol. Chem. 286, 3307–3314 (2011).

    CAS  Article  Google Scholar 

  45. Saeij, J. P. et al. Toxoplasma co-opts host gene expression by injection of a polymorphic kinase homologue. Nature 445, 324–327 (2007).

    CAS  Article  Google Scholar 

  46. Reese, M. L., Zeiner, G. M., Saeij, J. P., Boothroyd, J. C. & Boyle, J. P. Polymorphic family of injected pseudokinases is paramount in Toxoplasma virulence. Proc. Natl Acad. Sci. USA 108, 9625–9630 (2011).

    CAS  Article  Google Scholar 

  47. Butcher, B. A. et al. Toxoplasma gondii rhoptry kinase ROP16 activates STAT3 and STAT6 resulting in cytokine inhibition and arginase-1-dependent growth control. PLoS Pathog. 7, e1002236 (2011).

    CAS  Article  Google Scholar 

  48. Burger, E. et al. Loss of Paneth cell autophagy causes acute susceptibility to Toxoplasma gondii–mediated inflammation. Cell Host Microbe 23, 177–190.e4 (2018).

  49. Lopez-Yglesias, A. H., Burger, E., Araujo, A., Martin, A. T. & Yarovinsky, F. T-bet-independent Th1 response induces intestinal immunopathology during Toxoplasma gondii infection. Mucosal Immunol. 11, 921–931 (2018).

    CAS  Article  Google Scholar 

  50. Raetz, M. et al. Parasite-induced TH1 cells and intestinal dysbiosis cooperate in IFN-γ-dependent elimination of Paneth cells. Nat. Immunol. 14, 136–142 (2013).

    CAS  Article  Google Scholar 

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This work was supported by National Institute of Allergy and Infectious Diseases grants R01AI136538 and R01AI121090 and by the Burroughs Wellcome Foundation.

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Authors and Affiliations



A.S. and F.Y. conceived of the study, interpreted data and wrote the manuscript; A.S. performed and analyzed all experiments, except those in Fig. 6 and Supplementary Fig. 8 (performed by A.A. and E.T.C.). E.T.C. contributed to Supplementary Fig. 7. T.J.M. and M.R.E. contributed to Supplementary Fig. 3. D.P.B. contributed to Fig. 1a,b and Supplementary Fig. 1.

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Correspondence to Felix Yarovinsky.

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Integrated supplementary information

Supplementary Figure 1 Global gene transcriptome analysis of human PBMCs infected with T. gondii.

a, List of the most significant differentially expressed genes in human PBMCs infected with the Pru strain of T. gondii (MOI 3:1) for 12 h. b, Heat map of differentially expressed genes based on RNA-seq results of PBMCs infected with the RH strain of T. gondii (MOI 3:1) for 12 h.

Supplementary Figure 2 Identification of S100A11.

a, Amino acid peptides detected by mass spectrometry. The red boxes denote the most frequently detected peptides by mass spectrometry. The data shown are representative of three independent experiments. b, Complete gel images from Figs. 4c and 5. Dotted markings indicate the parts used for the figures.

Supplementary Figure 3 S100A11 participates in induction of CCL2.

ad, Knockdown of S100A11 in THP-1 cells was performed by siRNA targeting S100A11 or irrelevant targets (siRNA-GFP and ‘scrambled siRNA’). The efficiency of S100A11 knockdown was verified by immunoblot (a), qRT–PCR (b), and hS100A11-specific ELISA (c). THP-1 cells with the reduced S100A11 expression produced less CCL2 when infected with RH88 (c) or Pru (d) strains of T. gondii. The data shown (mean ± s.d.) are representative of three independent experiments. Each symbol represents an individual experimental sample.

Supplementary Figure 4 Gene ontology analysis identifies the RAGE pathway as activated in PBMCs infected by T. gondii (Pru strain).

Differentially expressed genes (fold change > 2, P < 0.001) in PBMCs (n = 5) identified by Ingenuity Pathway Analysis (IPA) software in response to the T. gondii Pru strain.

Supplementary Figure 5 Gene ontology analysis identifies the RAGE pathway as activated in PBMCs infected by T. gondii (RH88 strain).

Differentially expressed genes (fold change > 2, P < 0.001) in PBMCs (n = 5) identified by Ingenuity Pathway Analysis (IPA) software in response to T. gondii RH88 strain.

Supplementary Figure 6 Parasite invasion is required for induction of CCL2 responses.

a, Parental (TATi) and inducible profilin knockout parasites (ΔPRFe/PRFi) were grown for 4 d ± anhydrotetracycline (ATc), harvested and incubated with THP-1 cells at a 3:1 ratio for 16 h in triplicates. CCL2 expression was then measured by RT–PCR. The experiment shown is representative of five independent experiments performed. b, MYB- (3 μM) or DMSO-pretreated T. gondii parasites were added to THP-1 cells (MOI 3:1) for 16 h, and CCL2 expression was analyzed by RT–PCR. Each symbol represents an individual experimental sample. The data shown represent the mean ± s.d.

Supplementary Figure 7 Generation of S100a11 KO mice.

a, A schematic diagram of the CRISPR/Cas9 strategy used to generate S100a11-deficient mice and primer design used in the study. Exons 2 and 3 of the S100a11 gene were targeted by two sgRNAs depicted as sg#9 and sg#3. b, Representative genotyping of the targeted alleles with a set of primers S100A11 wtF and S100A11 wtR that result in PCR products of 2.7 kb for WT mice and 557 bp for the S100a11 KO allele, as a result of deletion of exons 2 and 3.

Supplementary Figure 8 S100A11 regulates monocyte recruitment during mucosal response to T. gondii.

a,b, WT and S100a11 KO mice (n = 5) were infected orally with T. gondii, and the presence of monocytes and neutrophils in small intestinal lamina propria (n = 3) was analyzed (a) and quantified by flow cytometry on day 7 after infection (b). c, CCL2 and IFN-γ secretion in small intestine. d, Parasite burden in small intestine (n = 5) was measured by qRT–PCR. e, Histological analysis of the small intestines (n = 5) of infected WT and S100a11 KO mice with 20 cysts of ME49 T. gondii on day 7 after infection. Image fields are representative of pathology in multiple tissue sections, and chosen sections were selected by blinded observation. f, Histological changes in the small intestine were analyzed on day 7 after infection based on an additive scoring system. The data shown (mean ± s.d.) are representative of three independent experiments. Each symbol represents an individual experimental sample, and unpaired two-tailed Student’s t test was used for statistical analysis; ns, not significant.

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Safronova, A., Araujo, A., Camanzo, E.T. et al. Alarmin S100A11 initiates a chemokine response to the human pathogen Toxoplasma gondii. Nat Immunol 20, 64–72 (2019).

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