Open Access

Biomarkers for immune thrombocytopenia

  • Lingjia Yu1,
  • Chunmei Zhang2,
  • Liping Zhang3,
  • Yongyu Shi4 and
  • Xuebin Ji1Email author
Contributed equally
Biomarker Research20153:19

https://doi.org/10.1186/s40364-015-0045-0

Received: 15 June 2015

Accepted: 6 July 2015

Published: 16 July 2015

Abstract

Immune thrombocytopenia is an autoimmune disease with abnormal biomarkers. Immune thrombocytopenia pathogenesis is a complicated process in which the patient’s immune system is activated by platelet autoantigens resulting in immune mediated platelet destruction or suppression of platelet production. The autoantibodies produced by autoreactive B cells against self antigens are considered to play a crucial role. In addition, biomarkers such as transforming growth factor-beta1,Toll-like receptors,T helper 1 andT helper 2 cytokine bias, Notch signaling and abnormal biomarker in megakaryocyte maturation are involved in the pathogenesis of this disease. With the genomewide association study on immune thrombocytopenia, more biomarkers will be founded in the future. They may provides a theoretical basis for the mechanism and treatment of immune thrombocytopenia.

Keywords

Immune thrombocytopenia Biomarker T cell B cell Pathogenesis

Introduction

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder in which the patient’s immune system is activated by platelet autoantigens resulting in immune-mediated platelet destruction and/or suppression of platelet production with the clinical manifestations of oral gingival and skin mucous membrane bleeding.

Biomarkers are very important to the pathogenesis of disease. Many abnormal immune biomarkers play crucial roles in ITP pathogenesis [1]. The abnormal B, T cell and some new biomarkers in ITP were introduced. It may help people to know the complicated pathogenesis of ITP.

Abnormal B cell immune biomarkers

ITP is an autoimmune disease. Glycoprotein (GP) specific autoantibodies (e.g., GPVI, GPIb/IX, GPIIb/IIIa autoantibodies) can be detected in most ITP patients’ plasma or platelet eluates by modified monoclonal antibody immobilization of platelet antigen (MAIPA) assay, which bind to the specific glycoproteins by an antigen-binding fragment (Fab) and then activate the mononuclear-macrophage or complement system [2, 3]. The autoantibodies produced by autoreactive B cells against self-antigens, specifically immunoglobulin G (IgG) antibodies against GPIIb/IIIa and/or GPIb/IX, are considered to play a crucial role in the plaletet destruction [4].

Approximately 75 % of platelet autoantigens are localized to either the platelet GP IIb/IIIa or GP Ib/IX complex. Inhibition of the binding of autoantibodies from several ITP patients by either another ITP autoantibody or by a monoclonal anti-GPIIb/IIIa antibody suggests that the antigenic repertoire in chronic ITP may be limited. Many patients may produce multiple antibodies. Once produced, antiplate autoantibodies may either bind to platelets, causing their destruction by either phagocytosis or possibly complement activation and lysis, or bind to megakaryocytes, resulting in decreased thrombopoiesis. A variety of new investigative techniques including MAIPA assay have localized a few autoantigens to specific regions of the cytoplasmic or extracellular regions of both GPIIb/IIIa and GPIb/IX. These methods that allow incubation of patient serum or plasma with intact platelets (MAIPA and immunobead) have greater sensitivity than techniques in which the patient antibody is tested against previously isolated platelet glycoproteins [5].

Platelets with affiliated IgG are targeted for exploitation by Fc receptor-mediated phagocytic cellular material within the reticuloendothelial system. The expression of FC gamma receptors (FCGR) IIb was decreased in ITP. Lower expression of FCGRIIb may be involved in the pathogenesis of ITP. An increasing in FCGRIIb may be considered as a therapeutic target for human ITP treatment or possibly as a new biomarker for ITP analysis [6].

It was demonstrated decreased expression of FCGRIIb and elevated expression of FCGRIIa and FCGRIII on monocytes in ITP patients before high-dose dexamethasone (HDDXM) therapy. HD-DXM treatment may change the FCGR balance toward the inhibitory FCGRIIb, thus providing new insights into the mechanism of HD-DXM in the treatment of ITP [7].

B-cell activating factor (BAFF; also known as B-lymphocyte stimulator) belonging to the family of tumor necrosis factor (TNF) ligands is critical for the maintenance of normal B-cell development, homeostasis, and autoreactivity [8, 9] and T-cell costimulation [1012]. BAFF is an important homeostatic cytokine for B cells that is up-regulated during inflammation and links adaptive with innate immunity. BAFF has been shown to enhance the expression of CD19 and mediate the maturation of autoreactive B cells. It is shown that BAFF is elevated in ITP patients with active disease, and excessive BAFF may rescue autoreactive B and T cells from apoptosis [13].

Abnormal T cell immune biomarkers

The cytokine transforming growth factor-beta1 (TGF-β1) is a central player in maintaining the immune response balance, which belongs to regulator T cell (Treg) cytokines. Tregs play crucial roles in the induction and maintenance of immune tolerance, which are involved in ITP abnormal T cell immunity. It was found that the concentration TGF-β1 was lower in ITP patients [14]. The dominant function of TGF-β1 is to regulate peripheral immune homeostasis [15].

Toll-like receptors (TLRs) are the major molecules involved in the immune regulatory process [16, 17]. TLRs play an important role in defending the host against pathogenic microbes through the induction of inflammatory cytokines and type I interferons. Furthermore, TLRs play roles in shaping pathogen-specific humoral and cellular adaptive immune responses [18]. TLRs have been found to be associated with immune-mediated diseases but it is still not clear whether they play a role in ITP, especially TLR4. CD4+ T-lymphocyte abnormalities, including T helper (Th)17. Th1, Th2, and Treg are considered important in ITP. It was showed that TLR4, CD4+ T cells (Th1, Th17 and Treg cells) and related cytokines may take part in the pathogenesis of ITP. TLR4 may play a role through the TLR4-cytokine-CD4+ T lymphocyte cell pathway [19].

Th1 polarization persists in the autoimmune response found in ITP. TLR7 expression, which also plays an important role in autoimmune diseases, was found increasing in ITP. The findings indicate that TLR7 promotes Th1 polarization and may contribute in ITP pathogenesis [20].

Th1/Th2 cytokine bias may be an important mechanism of ITP. The Th1/Th2 balance is important to normal human immunity. Th1 cells primarily secrete the inflammatory cytokines interleukin (IL)-2, IL-12, interferon-gamma (IFN-γ) and TNF-β. Th2 cells primarily secrete the inflammatory cytokines IL-4, IL-5, IL-6 and IL-10.

ITP is associated with a Th1 type of T helper cytokine response, while that of type Th2 is downregulated. The present study demonstrates that an imbalance of Th1 and Treg cytokines may mediate the pathogenesis of ITP [21]. Uncontrolled Th-1 lymphocyte activation may be an important mechanism of ITP. Treatment with a large dose of dexamethasone, the Th1-type cytokine spectrum returns to the dominant position after treatment with dexamethasone [22]. Shifting the cytokine patterns from Th1 to Th2 may be a potential immunotherapy for ITP.

Cytotoxic T-lymphocytes (CTLs) can induce the lysis of autologous platelets. CTLs-mediated platelet destruction and aberrant cytokine profiles play important roles in the pathogenesis of ITP. Interleukin-27 (IL-27) has pleiotropic immunomodulatory effects. The results suggest that IL-27 can inhibit CTL-mediated platelet destruction by negatively regulating CTL cytotoxicity toward platelets in ITP. IL-27 may have a therapeutic role in treating ITP patients [23].

Notch signaling has been implicated in peripheral T-cell activation and effector cell differentiation. Th17 cells and Treg cells, along with Th1 and Th2 cells, may contribute to the pathogenesis of ITP. The imbalance of Th17/Treg toward Th17 cells has been shown to play an important role in the peripheral immune response. However, the role of Th17/Treg in the pathogenesis of ITP and the effect of Notch signaling on Th17/Treg imbalances still remain uncertain in ITP [24].

To investigate the role of Notch signaling pathway in ITP, the expression of Notch pathway molecules in ITP patients were measured and evaluated their clinical relevance. It was found that Notch1 and Notch3 expression elevated, while Notch2 decreased statistically in ITP patients. The findings suggest that the Notch signaling pathway may be involved in ITP. The blockage of Notch1 pathway may be a promising therapeutic method [25].

Abnormal biomarker in ITP megakaryocyte maturation

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) belongs to the TNF super-family protein biomarkers. TRAIL can promote the apoptosis and maturation of megakaryocytes. It was demonstrated that low expression of TRAIL in megakaryocytes contributed to impaired platelet production in ITP. TRAIL expression on megakaryocytes and the TRAIL concentrations of ITP patients were decreased. Megakaryocyte apoptosis mediated by TRAIL in the plasma of ITP patients may be a potential mechanism by which the megakaryocyte number increases in vitro [26]. It was found that low dose decitabine can promote megakaryocyte maturation and platelet production and enhance TRAIL expression in megakaryocytes in healthy controls and ITP [27].

New biomarkers in ITP

Genetic sequence variations, such as single nucleotide polymorphisms (SNPs), may have biological roles in modifying the outcome risk of many diseases. Genomewide association study(GWAS) is a new method that can be used to find genetic characteristic SNPs of many complex disease by case–control association analysis [28, 29]. GWAS on ITP may find some genetic SNPs which can be developed to new biomarkers for the clinical practice, individualized diagnosis and treatment of ITP.

Conclusions

ITP is an autoimmune disease with abnormal immune biomarkers. The autoantibodies produced by autoreactive B cells against self-antigens, specifically antibodies against GPIIb/IIIa and/or GPIb/IX, are considered to play a crucial role in the pathogenesis of ITP. Biomarkers such as TGF-β1,TLRs, Notch signaling, TRAIL,Th1/Th2 cytokine bias are involved in ITP T cell abnormality. With the GWAS on ITP, more biomarkers will be founded in the future. They may provides a theoretical basis for the mechanism and treatment of ITP.

Notes

Abbreviations

ITP: 

immune thrombocytopenia

MAIPA: 

modified monoclonal antibody immobilization of platelet antigen

Treg: 

T regulatory cell

FCGR: 

FC gamma receptors

Th: 

T helper

TLR: 

toll-like receptors

IFN-γ: 

interferon-gamma

TGF-β: 

transforming growth factor-beta

IL: 

interleukin

TNF-β: 

tumor necrosis factor-beta

GP: 

glycoprotein

TRAIL: 

tumor necrosis factor-related apoptosis-inducing ligand

GWAS: 

genomewide association study

Declarations

Acknowledgements

The present study was partially supported by the National Natural Science Foundation (81100336), the Science and Technology development Plan of Shandong Province (2014GSF118035), the Natural Science, Foundation of Shandong Province (ZR2013HQ001), the Fundamental Research Funds of Shandong University (2015JC013,2015QLMS07), the Cultivation Fund of the Key Scientific and Technical Innovation Project, the Ministry of Education of China (NO704030), the Taishan Scholar Foundation, and the SRF for ROCS and SEM.

Authors’ Affiliations

(1)
Department of Hematology, Qilu Hospital, Shandong University
(2)
Department of Hematology, the central Hospital of TaiAn
(3)
Jinan Stomatological Hospital
(4)
Institute of Immunology, School of Medicine, Shandong University

References

  1. Ji X, Zhang L, Peng J, Hou M. T cell immune abnormalities in immune thrombocytopenia. J Hematol Oncol. 2014;7:72.PubMed CentralPubMedView ArticleGoogle Scholar
  2. Hou M, Stockelberg D, Kutti J, Wadenvik H. Antibodies against platelet GPIb/IX, GPIIb/IIIa, and other platelet antigens in chronic idiopathic thrombocytopenic purprua. Eur J Haematol. 1995;55:307–14.PubMedView ArticleGoogle Scholar
  3. Mc MR. Antiplatelet antibodies in chronic immune thrombocytopenia and their role in platelet destruction and defective platelet production. Hematol Oncol Clin North Am. 2009;23:1163–75.View ArticleGoogle Scholar
  4. McMillan R. Autoantibodies and autoantigens in chronic immune thrombocytopenic purprua. Semin Hematol. 2000;37:239–48.PubMedView ArticleGoogle Scholar
  5. Nugent D, McMillan R, Nichol JL, Slichter SJ. Pathogenesis of chronic immune thrombocytopenia: increased platelet destruction and/or decreased platelet production. Br J Haematol. 2009;146:585–96.PubMedView ArticleGoogle Scholar
  6. Wu Z, Zhou J, Prsoon P, Wei X, Liu X, Peng B. Low expression of FCGRIIB in macrophages of immune thrombocytopenia-affected individuals. Int J Hematol. 2012;96:588–93.PubMedView ArticleGoogle Scholar
  7. Liu XG, Ma SH, Sun JZ, Ren J, Shi Y, Sun L, et al. High-dose dexamethasone shifts the balance of stimulatory and inhibitory Fcgamma receptors on monocytes in patients with primary immune thrombocytopenia. Blood. 2011;117:2061–9.PubMedView ArticleGoogle Scholar
  8. Schneider P, MacKay F, Steiner V, Hofmann K, Bodmer JL, Holler N, et al. BAFF, a novel ligand of the tumor necrosis factor family, stimulates B cell growth. J Exp Med. 1999;189:1747–56.Google Scholar
  9. Moore PA, Belvedere O, Orr A, Pieri K, LaFleur DW, Feng P, et al. BLyS: member of the tumor necrosis factor family and B lymphocyte stimulator. Science. 1999;285:260–3.Google Scholar
  10. Huard B, Schneider P, Mauri D, Tschopp J, French LE. T cell costimulation by the TNF ligand BAFF. J Immunol. 2001;167:6225–31.PubMedView ArticleGoogle Scholar
  11. Ye Q, Wang L, Wells AD, Tao R, Han R, Davidson A, et al. BAFF binding to T cell-expressed BAFF-R costimulates T cell proliferation and alloresponses. Eur J Immunol. 2004;34:2750–9.Google Scholar
  12. Huard B, Arlettaz L, Ambrose C, Kindler V, Mauri D, Roosnek E, et al. BAFF production by antigen-presenting cells provides T cell co-stimulation. Int Immunol. 2004;16:467–75.Google Scholar
  13. Zhu XJ, Shi Y, Peng J, Guo CS, Shan NN, Qin P, et al. The effects of BAFF and BAFF-R-Fc fusion protein in immune thrombocytopenia. Blood. 2009;114:5362–7.Google Scholar
  14. Ma L, Liang Y, Fang M, Guan Y, Si Y, Jiang F, et al. The cytokines (IFN-gamma, IL-2, IL-4, IL-10, IL-17) and Treg cytokine (TGF-beta1) levels in adults with immune thrombocytopenia. Pharmazie. 2014;69:694–7.Google Scholar
  15. Malhotra N, Kang J. SMAD regulatory networks construct a balanced immune system. Immunology. 2013;139:1–10.PubMed CentralPubMedView ArticleGoogle Scholar
  16. Zhu J, He S, Du J, Wang Z, Li W, Chen X, et al. Local administration of a novel Toll-like receptor 7 agonist in combination with doxorubicin induces durable tumouricidal effects in a murine model of T cell lymphoma. J Hematol Oncol. 2015;8:21.Google Scholar
  17. Isaza-Correa JM, Liang Z, van den Berg A, Diepstra A, Visser L. Toll-like receptors in the pathogenesis of human B cell malignancies. J Hematol Oncol. 2014;7:57.Google Scholar
  18. Kumar H, Kawai T, Akira S. Toll-like receptors and innate immunity. Biochem Biophys Res Commun. 2009;388:621–5.PubMedView ArticleGoogle Scholar
  19. Liu H, Ouyang X, Li Y, Zeng H, Wang X, Xie S, et al. Involvement of levels of Toll like receptor-4 in monocytes, CD4+ T-lymphocyte subsets, and cytokines in patients with immune thrombocytopenic purpura. Thromb Res. 2013;132:196–201.Google Scholar
  20. Yang Q, Wang B, Yu H, Zhu Y, Wang X, Jiang H, et al. TLR7 promotes Th1 polarization in immune thrombocytopenia. Thromb Res. 2011;128:237–42.Google Scholar
  21. Andersson J. Cytokines in idiopathic thrombocytopenic purpura (ITP). Thromb Res. 2013;132:196–201.View ArticleGoogle Scholar
  22. Ma D, Zhu X, Zhao P, Zhao C, Li X, Zhu Y, et al. Profile of Th17 cytokines (IL-17, TGF-beta, IL-6) and Th1 cytokine (IFN-gamma) in patients with immune thrombocytopenic purpura. Ann Hematol. 2008;87:899–904.Google Scholar
  23. Zhou H, Qiu JH, Wang T, Yu YY, Liu XN, Li X, et al. Interleukin 27 inhibits cytotoxic T-lymphocyte-mediated platelet destruction in primary immune thrombocytopenia. Blood. 2014;124:3316–9.Google Scholar
  24. Yu S, Liu C, Li L, Tian T, Wang M, Hu Y, et al. Inactivation of Notch signaling reverses the Th17/Treg imbalance in cells from patients with immune thrombocytopenia. Lab Invest. 2015;95:157–67.Google Scholar
  25. Ma D, Dai J, Zhu X, Yan S, Zhao P, Zhang J, et al. Aberrant expression of Notch signaling molecules in patients with immune thrombocytopenic purpura. Ann Hematol. 2010;89:155–61.Google Scholar
  26. Yang L, Wang L, Zhao CH, Zhu XJ, Hou Y, Peng J, et al. Contributions of TRAIL mediated megakaryocyte apoptosis to impaired megakaryocyte and platelet production in immune thrombocytopenia. Blood. 2010;116:4307–16.Google Scholar
  27. Zhou H, Hou Y, Liu X, Qiu J, Feng Q, Wang Y, et al. Low-dose decitabine promotes megakaryocyte maturation and platelet production in healthy controls and immune thrombocytopenia. Thromb Haemost. 2015;113:1021–34.Google Scholar
  28. Yang TH, Kon M, DeLisi C. Genome-wide association studies. Methods Mol Biol. 2013;939:233–51.PubMedView ArticleGoogle Scholar
  29. Nakabayashi K, Tajima A, Shirasawa S. Genome-wide association studies: recent advances and future directions. Nihon Rinsho. 2009;67:469–76.PubMedGoogle Scholar

Copyright

© Yu et al. 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

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