Abstract:Objective: To study the effect of microrna-205-5p (mir-205-5p) targeting high mobility group protein B1 / toll like receptor 4 (HMGB1 / TLR4) pathway on immune function of allergic rhinitis (AR). Methods: 60 male rats were selected and divided into normal control group (group A), allergic rhinitis group (group B), allergic rhinitis + miR-205-5p agomir group (group C), allergic rhinitis + miR-205- 5p antagomir group (group D) included 4 groups of 15 animals in each group. Group A did not receive any treatment, while groups B, C, and D were sensitized with ovalbumin nasal enhancement to establish AR models. After the model was established, 300 μg miR-205-5p agomir was injected into the tail of group C, miR-205-5p antagomir was injected into the tail of group D, and normal saline was injected into both groups A and B. One week later, the behavioral and immune-related indexes of each group [interferon-γ (IFN-γ), interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10), Immunoglobulin E (IgE)], nasal mucosal inflammatory response, tight junctions between epithelial cells, endoplasmic reticulum morphology and expression of tight junction proteins, HMGB1/TLR4 pathway proteins. The targeting relationship between miR-205-5p and TLR4 was analyzed using a dual-luciferase reporter assay. Results: The behavioral score, IL-4, IgE, HMGB1, TLR4, NF-κB expression and tight junction width of each group from low to high were group A < group B < group C < group D; IFN-γ, IL-2 The expression levels of IL-10, IL-10 and tight junction protein from low to high were group D < group C < group B < group A, and the differences between groups were statistically significant (all P < 0.05). The dual-luciferase reporter results indicated that miR-205-5p could target TLR4.Conclusion: miR-205-5p can target the HMGB1/TLR4 pathway to inhibit the AR immune disorder caused by Th1/Th2 imbalance, strengthen the barrier function of the nasal mucosa, thereby reducing the invasion of allergens, relieving AR-related symptoms, and having a positive effect on the treatment of AR .