Human Dental Pulp Stem Cells Modulate Acute Inflammation Kinetics in the AIRmax Murine Model by Sustained TNF-Alpha Suppression and Transient Homing.

Abstract

Mesenchymal stem cells (MSCs) are multipotent adult cells that are highly valued for their immunomodulatory potential and intrinsic ability to home to inflamed sites. This study specifically utilized human dental pulp stem cells (hDPSCs), a unique MSC subtype derived from the neural crest, due to their reported superior anti-inflammatory capacity. To rigorously test their efficacy, we employed the AIRmax murine model, which exhibits a genetically determined high-inflammatory phenotype. Acute inflammation was induced by subcutaneous injection of the polyacrylamide suspension Biogel P-100. Two hours post-induction, AIRmax mice were treated intravenously with hDPSCs. Our results demonstrate that hDPSC treatment produced significant anti-inflammatory effects evident at 24 h. The treated group showed a pronounced reduction in leukocyte migration and decreased protein extravasation in the inflammatory exudate. Crucially, hDPSCs also modulated molecular mediators, significantly decreasing the pro-inflammatory cytokine TNF-alpha and reactive oxygen species (ROS) production. Furthermore, while hDPSCs efficiently and rapidly homed to the inflammation site within 2 h, their maximal therapeutic benefits only manifested after 24 h. This suggests that their robust capacity to modulate acute inflammatory responses relies not only on rapid migration but also on a paracrine "hit-and-run" mechanism that suppresses cellular infiltration and oxidative stress over time. This study reinforces the potential of hDPSCs as a powerful, multi-target therapeutic agent for inflammatory conditions, supporting further investigation into their precise mechanisms and clinical application.