Aspirin Blocks Orthodontic Relapse via Inhibition of CD4+ T Lymphocytes

• Published in: Journal of dental research 2017-05, Vol.96 (5), p.586-594
• Main Authors: Liu, Y., Zhang, T., Zhang, C., Jin, S.S., Yang, R.L., Wang, X.D., Jiang, N., Gan, Y.H., Kou, X.X., Zhou, Y.H.
• Format: Article
• Language: English
• Subjects: Adapter proteins; Animals; Anti-inflammatory agents; Aspirin; Aspirin - pharmacology; CD25 antigen; CD4 antigen; CD4-Positive T-Lymphocytes - immunology; Cytokines; Dentistry; Enzyme-Linked Immunosorbent Assay; Etanercept; Flow Cytometry; Immunosuppressive agents; Inflammation; Interferon-gamma - metabolism; Lymphocytes; Lymphocytes T; Male; Maxilla - diagnostic imaging; Monoclonal antibodies; Nonsteroidal anti-inflammatory drugs; Orthodontics; Osteoclasts - immunology; Periodontal ligament; Rats; Rats, Sprague-Dawley; Recurrence; Serum levels; Silicones; Spleen; Spleen - cytology; Statistical analysis; Studies; Th1 Cells - immunology; Tomography; Tooth Movement Techniques; Tumor Necrosis Factor-alpha - metabolism; Tumor necrosis factor-TNF; Tumor necrosis factor-α; X-Ray Microtomography; γ-Interferon
• ISSN: 0022-0345; 1544-0591
• DOI: 10.1177/0022034516685527

Immunologic response plays an important role in orthodontic tooth movement (OTM) and relapse. Nonsteroidal anti-inflammatory drugs, such as aspirin, affect immune cells and clinical orthodontic treatment. However, the mechanisms by which nonsteroidal anti-inflammatory drugs regulate immune cells to affect orthodontic relapse are unclear. In this study, male Sprague-Dawley rats were grouped as relapse and relapse + aspirin for 10 d after 14 d of OTM. Silicone impressions of the rats’ maxillary dentitions were obtained to record the distance of OTM at the indicated time point. CD4+ T lymphocytes in spleen were examined by flow cytometry. Serum levels of type 1 T-helper (Th1) cell–associated cytokines tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ) were determined through enzyme-linked immunosorbent assay. The effects of aspirin on CD4+ T and Th1 cells were also analyzed in vitro. Aspirin treatment significantly reduced the relapse rate. More interestingly, injection of CD25 neutralizing antibody basiliximab or TNF-α inhibitor etanercept can significantly reduce the relapse rate as well. Correspondingly, aspirin treatment significantly accelerated the decrease of orthodontic force–induced secretion of TNF-α and IFN-γ in serum and the expression of TNF-α and IFN-γ in periodontal ligament during relapse. Furthermore, aspirin treatment in vitro significantly repressed the differentiation of CD4+ T and Th1 cells. Overall, results indicated that aspirin treatment can block orthodontic relapse by regulating Th1 cells.