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Demonstration of innate immune responses in the thyroid gland: potential to sense danger and a possible trigger for autoimmune reactions.

ABSTRACT:

Background

Autoimmune thyroid disease is an archetypal organ-specific autoimmune disorder that is characterized by the production of thyroid autoantibodies and lymphocytic infiltration into the thyroid. However, the underlying mechanisms by which specific thyroid antibodies are produced are largely unknown. Recent studies have shown that innate immune responses affect both the phenotype and the severity of autoimmune reactions. Moreover, it appears that even non-immune cells, including thyroid cells, have an ability to launch such responses. The aim of this study was to conduct a more detailed analysis of innate immune responses of the thyroid upon stimulation with various "non-self" and "self" factors that might contribute to the initiation of autoimmune reactions.

Methods

We used rat thyroid FRTL-5 cells, human thyroid cells, and mice to investigate the effects of various pathogen-associated molecular patterns (PAMPs), danger-associated molecular patterns (DAMPs), and iodide on gene expression and function that were related to innate immune responses.

Results

RT-PCR analysis showed that both rat and human thyroid cells expressed mRNAs for Toll-like receptors (TLRs) that sensed PAMPs. Stimulation of thyrocytes with TLR ligands resulted in activation of the interferon-beta (IFN-?) promoter and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF?B)-dependent promoter. As a result, pro-inflammatory cytokines, chemokines, and type I interferons were produced. Similar activation was observed when thyroid cells were stimulated with double-stranded DNA, one of the typical DAMPs. In addition to these PAMPs and DAMPs, treatment of thyroid cells with high concentrations of iodide increased mRNA expression of various cytokines.

Conclusion

We show that thyroid cells express functional sensors for exogenous and endogenous dangers, and that they are capable of launching innate immune responses without the assistance of immune cells. Such responses may relate to the development of thyroiditis, which in turn may trigger autoimmune reactions.

SUBMITTER: Kawashima A

PROVIDER: S-EPMC3610444 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Publications

Demonstration of innate immune responses in the thyroid gland: potential to sense danger and a possible trigger for autoimmune reactions.

Kawashima Akira A Yamazaki Kazuko K Hara Takeshi T Akama Takeshi T Yoshihara Aya A Sue Mariko M Tanigawa Kazunari K Wu Huhehasi H Ishido Yuko Y Takeshita Fumihiko F Ishii Norihisa N Sato Kanji K Suzuki Koichi K

Thyroid : official journal of the American Thyroid Association 20130318 4

<h4>Background</h4>Autoimmune thyroid disease is an archetypal organ-specific autoimmune disorder that is characterized by the production of thyroid autoantibodies and lymphocytic infiltration into the thyroid. However, the underlying mechanisms by which specific thyroid antibodies are produced are largely unknown. Recent studies have shown that innate immune responses affect both the phenotype and the severity of autoimmune reactions. Moreover, it appears that even non-immune cells, including t ...[more]

PMID: 23234343

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Dataset Information

Demonstration of innate immune responses in the thyroid gland: potential to sense danger and a possible trigger for autoimmune reactions.

Background

Methods

Results

Conclusion

Publications

Demonstration of innate immune responses in the thyroid gland: potential to sense danger and a possible trigger for autoimmune reactions.

Similar Datasets

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