An Antigen-Specific T Cell-Mediated Mouse Model for Oral Lichen Planus-Like Lesions: A Preliminary Study

Background The lack of an appropriate animal model has hindered the study of the precise aetiology and targeted therapy of oral lichen planus (OLP). Herein, we aimed to establish a reliable OLP-like mouse model using keratin 14-soluble ovalbumin transgenic mice and adoptive transfer of OT-I mice splenocytes. Methods A preconditioning step of a sublethal irradiation preconditioning step was followed by adoptive transfer of OVA-specific OT-I splenocytes. Histopathological and immunohistochemical analyses of buccal and tongue mucosa were performed to assess critical features of OLP. Results The keratin 14-soluble ovalbumin/OT-I adoptive transfer model induced a progressive inflammatory syndrome, which was not observed in wild-type controls. Mice in this model developed oral mucosal erythema, scaling, conjunctivitis, significant weight loss, and mortality. Histopathological examination revealed the hydropic degeneration and necrosis of basal keratinocytes, a band-like lymphocytic infiltration at the epithelial-lamina propria junction, and epithelial disruption. Immunohistochemistry confirmed a T cell-dominant (CD8⁺) infiltrate with sparse B cells (CD20⁺), aligning with the human OLP phenotype. Conclusion We developed a stable and antigen-specific mouse model that recapitulates the key immunopathological features of OLP. This model, driven by defined T cell-mediated cytotoxicity against epithelial antigen, provides a physiologically relevant platform for investigating OLP pathogenesis and evaluating novel targeted therapies.