Photodynamic therapy mediates innate immune responses via fibroblast–macrophage interactions


Antibacterial photodynamic therapy (PDT) has come to attract attention as an alternative therapy for drug-resistant bacteria. Recent reports revealed that antibacterial PDT induces innate immune response and stimulates abundant cytokine secretion as a part of inflammatory responses. However, the underlying mechanism how antibacterial PDT interacts with immune cells responsible for cytokine secretion has not been well outlined. In this study, we aimed to clarify the difference in gene expression and cytokine secretion between combined culture of fibroblasts and macrophages and their independent cultures. SCRC-1008, mouse fibroblast cell line and J774, mouse macrophage-like cell line were co-cultured and PDT treatments with different parameters were carried out. After various incubation periods (1–24 h), cells and culture medium were collected, and mRNA and protein levels for cytokines were measured using real-time PCR and ELISA, respectively. Our results showed that fibroblasts and macrophages interact with each other to mediate the immune response. We propose that fibroblasts initially respond to PDT by expressing Hspa1b, which regulates the NF-κB pathway via Tlr2 and Tlr4. Activation of the NF-κB pathway then results in an enhanced secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and neutrophil chemoattractant MIP-2 and KC from macrophages.

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  1. 1.

    Tanaka M, Mroz P, Dai T, Huang L, Morimoto Y, Kinoshita M, et al. Photodynamic therapy can induce a protective innate immune response against murine bacterial arthritis via neutrophil accumulation. PLoS One. 2012;7(6):e39823. doi:10.1371/journal.pone.0039823.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  2. 2.

    Tanaka M, Kinoshita M, Yoshihara Y, Shinomiya N, Seki S, Nemoto K, et al. Photodynamic therapy using intra-articular photofrin for murine MRSA arthritis: biphasic light dose response for neutrophil-mediated antibacterial effect. Lasers Surg Med. 2011;43(3):221–9.

    PubMed Central  Article  PubMed  Google Scholar 

  3. 3.

    Asea A, Rehli M, Kabingu E, Boch JA, Baré O, Auron PE, et al. Novel signal transduction pathway utilized by extracellular HSP70: role of toll-like receptor (TLR) 2 and TLR4. J Biol Chem. 2002;277(17):15028–34.

    CAS  Article  PubMed  Google Scholar 

  4. 4.

    Folkesson HG, Matthay MA, Hebert CA, Broaddus VC. Acid aspiration-induced lung injury in rabbits is mediated by interleukin-8-dependent mechanisms. J Clin Investig. 1995;96(1):107–16. doi:10.1172/JCI118009.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  5. 5.

    Porat R, Poutsiaka DD, Miller LC, Granowitz EV, Dinarello CA. Interleukin-1 (IL-1) receptor blockade reduces endotoxin and Borrelia burgdorferi-stimulated IL-8 synthesis in human mononuclear cells. FASEB J. 1992;6(7):2482–6.

    CAS  PubMed  Google Scholar 

  6. 6.

    Jourdan T, Godlewski G, Cinar R, Bertola A, Szanda G, Liu J, et al. Activation of the Nlrp3 inflammasome in infiltrating macrophages by endocannabinoids mediates beta cell loss in type 2 diabetes. Nat Med. 2013;19(9):1132–40.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  7. 7.

    Westwell-Roper CY, Ehses JA, Verchere CB. Resident macrophages mediate islet amyloid polypeptide-induced islet IL-1β production and β-cell dysfunction. Diabetes. 2014;63(5):1698–711. doi:10.2337/db13-0863.

    CAS  Article  PubMed  Google Scholar 

  8. 8.

    Korbelik M, Sun J, Cecic I. Photodynamic therapy-induced cell surface expression and release of heat shock proteins: relevance for tumor response. Cancer Res. 2005;65(3):1018–26.

    CAS  PubMed  Google Scholar 

  9. 9.

    Luna MC, Ferrario A, Wong S, Fisher AMR, Gomer CJ. Photodynamic therapy-mediated oxidative stress as a molecular switch for the temporal expression of genes ligated to the human heat shock promoter. Cancer Res. 2000;60(6):1637–44.

    CAS  PubMed  Google Scholar 

  10. 10.

    Mambula SS, Calderwood SK. Heat shock protein 70 is secreted from tumor cells by a nonclassical pathway involving lysosomal endosomes. J Immunol. 2006;177(11):7849–57. doi:10.4049/jimmunol.177.11.7849.

    CAS  Article  PubMed  Google Scholar 

  11. 11.

    Frasch SC, Henson PM, Nagaosa K, Fessler MB, Borregaard N, Bratton DL. Phospholipid flip-flop and phospholipid scramblase 1 (PLSCR1) co-localize to uropod rafts in formylated Met-Leu-Phe-stimulated neutrophils. J Biol Chem. 2004;279(17):17625–33. doi:10.1074/jbc.M313414200.

    CAS  Article  PubMed  Google Scholar 

  12. 12.

    John K, Schreiber S, Kubelt J, Herrmann A, Müller P. Transbilayer movement of phospholipids at the main phase transition of lipid membranes: implications for rapid flip-flop in biological membranes. Biophys J. 2002;83(6):3315–23. doi:10.1016/S0006-3495(02)75332-0.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  13. 13.

    Asea A. Chaperokine-induced signal transduction pathways. Exerc Immunol Rev. 2003;9:25–33.

    PubMed Central  PubMed  Google Scholar 

  14. 14.

    Botzler C, Li G, Issels RD, Multhoff G. Definition of extracellular localized epitopes of Hsp70 involved in an NK immune response. Cell Stress Chaperones. 1998;3(1):6–11.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  15. 15.

    Lawrence T. The nuclear factor NF-κB pathway in inflammation. Cold Spring Harb Perspect Biol. 2009;1(6):a001651. doi:10.1101/cshperspect.a001651.

    PubMed Central  Article  PubMed  Google Scholar 

  16. 16.

    Knott PG, Gater PR, Dunford PJ, Fuentes ME, Bertrand CP. Rapid up-regulation of CXC chemokines in the airways after Ag-Specific CD4+ T cell activation. J Immunol. 2001;166(2):1233–40. doi:10.4049/jimmunol.166.2.1233.

    CAS  Article  PubMed  Google Scholar 

  17. 17.

    Miura M, Fu X, Zhang Q-W, Remick DG, Fairchild RL. Neutralization of Groα and macrophage inflammatory protein-2 attenuates renal ischemia/reperfusion injury. Am J Pathol. 2001;159(6):2137–45. doi:10.1016/S0002-9440(10)63065-9.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

  18. 18.

    Roche JK, Keepers TR, Gross LK, Seaner RM, Obrig TG. CXCL1/KC and CXCL2/MIP-2 are critical effectors and potential targets for therapy of Escherichia coli O157:H7-associated renal inflammation. Am J Pathol. 2007;170(2):526–37. doi:10.2353/ajpath.2007.060366.

    PubMed Central  CAS  Article  PubMed  Google Scholar 

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This study was supported in part of JSPS research Grant (to Y. Morimoto) and a Grant from Okinaka Memorial Institute for Medical Research (to Y. Morimoto). We thank M. Yano, A. Majima and Y. Iida (National Defense Medical College, NDMC) for their technical assistance.

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The authors declare that they have no conflict of interest.

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Correspondence to Y. Morimoto.

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Zulaziz, N., Azhim, A., Himeno, N. et al. Photodynamic therapy mediates innate immune responses via fibroblast–macrophage interactions. Human Cell 28, 159–166 (2015).

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  • Immune response
  • Macrophage
  • Fibroblast
  • PDT
  • Neutrophil migration