Immunomodulation for Tissue Repair and Regeneration

Abstract

Various immune cells participate in repair and regeneration following tissue injury or damage, orchestrating tissue inflammation and regeneration processes. A deeper understanding of the immune system's involvement in tissue repair and regeneration is critical for the development of successful reparatory and regenerative strategies. Here we review recent technologies that facilitate cell-based and biomaterial-based modulation of the immune systems for tissue repair and regeneration. First, we summarize the roles of various types of immune cells in tissue repair. Second, we review the principle, examples, and limitations of regulatory T (Treg) cell-based therapy, a representative cell-based immunotherapy. Finally, we discuss biomaterial-based immunotherapy strategies that aim to modulate immune cells using various biomaterials for tissue repair and regeneration.

Keywords: Biomaterial; Immunomodulation; M2 macrophage; Regulatory T (Treg) cell; Tissue repair.

Fig. 1

Steps of the tissue repair process and immune cells in chronological order. Reprinted with permission from ref [1].

Fig. 2

Interaction of Treg cells with various immune cells. Reprinted with permission from ref [56].

Fig. 3

Various strategies of Treg cell-based therapies. Reprinted with permission from ref [97].

Fig. 4

A Schematic showing DNAzyme gold particles with three types of particles. Active (Dz), inactive (i-Dz) and nonspecific (Dz-NS) DNAzyme. TNF-α expression levels B when macrophages were treated with each group at 24 h in vitro and C when injected into a rat model of MI at 3 days. Restoration in cardiac function determined through analysis of D fractional shortening and € ejection fraction. Reprinted with permission from ref [118].

Fig. 5

Mechanism of multifunctional hydrogels for ROS scavenging and oxygen generation. Reprinted with permission from ref [172].