Longitudinal Change in CD86 Expression Is Associated with Regression of Cervical Intraepithelial Neoplasia

Background/Objectives: Cervical intraepithelial neoplasia (CIN) exhibits heterogeneous clinical behavior, with some lesions regressing spontaneously, whereas others persist or progress to higher-grade disease. Identifying biomarkers that reflect lesion dynamics remains a major clinical challenge. This study aimed to evaluate the clinical significance of CD86 expression in cervical lesions by examining longitudinal changes and determining whether temporal alterations in CD86 expression are associated with lesion regression and epithelial-associated immune dynamics. Methods: Cervical samples were collected from patients with CIN, and gene expression was analyzed using reverse transcription–quantitative PCR. Longitudinal analyses were performed using paired samples to evaluate the temporal changes in CD86 expression. Regression status and time to regression were assessed, and associations with CD86 changes were evaluated using receiver operating characteristic analysis, logistic regression, and Cox proportional hazards models. Longitudinal patterns were further characterized using a spaghetti plot and slope analyses. Results: Baseline CD86 expression did not associate with regression status or CIN grade. However, longitudinal changes in CD86 expression differed significantly between the regression and non-regression group. CD86 change demonstrated moderate predictive performance for regression and was significantly associated with both regression and shorter time to regression. Longitudinal analyses revealed distinct temporal patterns between the regression and progression groups. Baseline CD86 expression was strongly correlated with FOXP3 expression, whereas CD86 dynamics were not independently associated with lymphocyte-related markers. Conclusions: Longitudinal changes in CD86 expression are significantly associated with lesion regression in CIN and may reflect lesion-associated immune dynamics during follow-up, particularly within epithelial-derived cervical cytology specimens.