BioDrugs

, Volume 24, Issue 4, pp 225–235 | Cite as

CpG Oligodeoxynucleotides as TLR9 Agonists

Therapeutic Application in Allergy and Asthma
Review Article

Abstract

Unmethylated cytosine-phosphate-guanine (CpG) dinucleotides in microbial DNA sequences activate Toll-like receptor (TLR) 9, and previous studies have shown that oligodeoxynucleotides (ODNs) containing CpG in specific base sequence motifs (CpG ODNs) can reiterate the majority of the immunomodulatory effects produced by bacterial DNA. Many of the manifestations in allergic diseases are primarily due to T helper (Th)-2 cell-type responses. CpG ODNs can induce Th1 and T-regulatory (Treg) cell-type cytokines that can suppress the Th2 response. The therapeutic application of TLR9 has been explored extensively in recent years, and many studies are being conducted to assess the safety and efficacy of TLR9 agonists in various diseases, including atopic and infectious diseases, and cancer. Studies in murine models have shown that the development of atopic airway disease can be prevented by treatment with CpG ODNs. Various clinical trials are currently ongoing to determine the efficacy of CpG ODNs as a therapeutic tool for atopic diseases. In this review, we discuss the therapeutic application of CpG ODNs in allergy and asthma. CpG ODNs may be used alone or as an adjuvant to immunotherapy to treat these disorders.

Notes

Acknowledgments

This work was supported by NIH grant 1R01AI075315. The authors have no conflicts of interest directly relevant to the content of this review.

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Authors and Affiliations

  1. 1.Center for Clinical and Translational Science, Department of Biomedical SciencesCreighton University School of MedicineOmahaUSA

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