Beyond Molecular Markers: The Therapeutic Significance of Mesenchymal Stem Cell Deformability in Regenerative Medicine.

Mesenchymal stem cells (MSCs) are characterized by their unique therapeutic properties, which include the ability to differentiate, secrete paracrine factors, and migrate toward sites of tissue injury. Although classical molecular markers facilitate phenotypic characterization, they do not always reflect the true functional capacity of MSCs. This article introduces deformability, i.e., the capacity of cells to deform under mechanical forces, as a novel, integrative marker of MSC biological quality. It examines the relationship between cellular mechanical deformability and key therapeutic attributes, such as stemness, homing ability, and differentiation status. It overviews current measurement techniques, categorized by resolution, throughput, and clinical applicability. The potential applications of deformability in quality control and cell sorting for therapeutic purposes are also discussed. The article proposes that, in addition to molecular features, deformability may serve as a functional biomarker, potentially enhancing the effectiveness of MSC-based therapies.