Robustness of tissues refers to their capability to maintain normal functions despite perturbation such as injuries. Recent studies suggest a key role of the immune system in injury repair. In this process, several immune cell lineages exhibit considerable plasticity as they migrate toward the site of damage and contribute to repair. For example, myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of immature cells and possess phenotypic plasticity in cancer, a pathological status that is considered as “wounds that do not heal.” They are characterized by their potent ability to suppress immune responses. In cutaneous wound healing, MDSCs not only execute their immunosuppressive function to inhibit inflammation but also stimulate cell proliferation once they adopt a fate of a totally different cell type. At a molecular level, we found that Krüppel-like factor 4 (KLF4), a transcription factor with multiple roles in homeostasis and disease development plays a critical role in regulating MDSCs. In this review, KLF4-mediated plasticity of MDSCs and the underlying mechanisms are discussed.
Part of the book: Cells of the Immune System