AIM2 Inflammasome Is Critical for dsDNA-Induced IL-1β Secretion in Human Dental Pulp Cells
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The AIM2 inflammasome pathway has been determined to play an important role in cellular immune defense against bacterial and viral infections; however, its function and regulatory mechanism in human dental pulp cells (HDPCs) during pulpitis remains poorly understood. In this study, we explored whether the AIM2 inflammasome pathway was activated in HDPCs in response to dsDNA and defined its role in regulating IL-1β secretion. We demonstrated that stimulation with IFN-γ and cytoplasmic DNA significantly activated the AIM2 inflammasome and increased IL-1β secretion in HDPCs. Moreover, AIM2 overexpression significantly up-regulated both cleaved Caspase-1 expression and IL-1β release in HDPCs, while suppression of ASC and Caspase-1 resulted in down-regulation of cleaved Caspase-1 and IL-1β secretion. These results suggest that Caspase-1-dependent IL-1β processing and secretion require the AIM2 inflammasome pathway in HDPCs and that the AIM2 inflammasome pathway is critical for regulation of the dental pulp immune response.
KEY WORDSabsent in melanoma 2 (AIM2) inflammasome pathway cytoplasmic DNA IL-1β human dental pulp
This study was supported by the National Natural Science Foundation of China (81670984) and the Science and Technology International Cooperation Projects of Guangdong Province (2016B050502008).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Research Involving Human Participants
All procedures performed in studies involving human participants were in accordance with the ethical standards of the ethics committee of the Guanghua School of Stomatology, Sun Yat-Sen University and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
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