Abstract
Background/Objectives: Osteoarthritis (OA) is a chronic inflammatory disease with limited disease-modifying therapies. This study explored a novel immunomodulatory approach using autologous, antigen-pulsed semi-mature dendritic cells (DCs) to modulate the inflammatory milieu in knee OA patients. Methods: In this open-label, quasi-experimental study, 29 subjects received a single subcutaneous injection of autologous DCs. Outcomes assessed at baseline and 4 weeks included the WOMAC index for symptoms and serum levels of IL-6 and TNF-α. Responses were analyzed in the overall cohort and by BMI subgroups. Results: The overall cohort showed a non-significant trend in WOMAC improvement (p = 0.080) and no change in IL-6 (p = 0.785) or TNF-α (p = 0.330). Subgroup analysis revealed differential patterns of response: WOMAC scores improved significantly only in normal-weight patients (p = 0.030), while serum TNF-α decreased significantly only in overweight patients (p = 0.025). IL-6 levels were unchanged across all groups. Conclusions: Autologous antigen-pulsed DC administration was associated with differential responses across BMI subgroups. Symptomatic benefit was observed in normal-weight individuals, while a reduction in systemic TNF-α occurred in overweight patients. These findings suggest that the host metabolic state may modulate the response to DC-based immunotherapy, and therefore warrant validation in a randomized, placebo-controlled trial.