The Critical Role of Cell Homing in Cytotherapeutics and Regenerative Medicine

Abstract

Recent advances in cell science and regenerative therapies mimic the therapeutic effects of patients’ own cells when they home to and accumulate at sites of injury. Inspired by stem cell trafficking under in vivo conditions, the facilitation of stem cell homing and the driving of endogenously mobilized mesenchymal stem cells (MSCs) for advanced therapeutics have shown indisputable success in several preclinical studies. In fact, stem cell homing is also relevant for cell transplantation. Ensuring that a sufficient number of transplanted cells arrive at the targeted region is a prerequisite for treatments to be successful, particularly when culture-expanded cells are injected intravenously. In this progress report, the authors discuss the important role of cell homing following i) the delivery of ex vivo-manipulated cellular materials, ii) the transplantation of bone marrow in a bone marrow transplant procedure, and iii) endogenous cell mobilization/recruitment in response to injury and disease. Considering a paradigm shift from in vitro tissue engineering to in situ tissue regeneration, current endeavors and future potential in the topics of chemokine-guided cell homing and the design of cell-comfortable scaffolds that combine both biochemical and biophysical cues for immunomodulation and in situ tissue regeneration are highlighted.