Reverse Adverse Immune Microenvironments by Biomaterials Enhance the Repair of Spinal Cord Injury

Abstract

Spinal cord injury (SCI) is a severe and traumatic disorder that ultimately results in the loss of motor, sensory, and autonomic nervous function. After SCI, local immune inflammatory response persists and does not weaken or disappear. The interference of local adverse immune factors after SCI brings great challenges to the repair of SCI. Among them, microglia, macrophages, neutrophils, lymphocytes, astrocytes, and the release of various cytokines, as well as the destruction of the extracellular matrix are mainly involved in the imbalance of the immune microenvironment. Studies have shown that immune remodeling after SCI significantly affects the survival and differentiation of stem cells after transplantation and the prognosis of SCI. Recently, immunological reconstruction strategies based on biomaterials have been widely explored and achieved good results. In this review, we discuss the important factors leading to immune dysfunction after SCI, such as immune cells, cytokines, and the destruction of the extracellular matrix. Additionally, the immunomodulatory strategies based on biomaterials are summarized, and the clinical application prospects of these immune reconstructs are evaluated.

Pathophysiology and Therapeutic Approaches for Spinal Cord Injury

“…Peripheral immune cells invade the injury site and chronically persist within the spinal cord [22]. Fibroblasts, which infiltrate from the periphery or differentiate from other resident cells, deposit inhibitory extracellular matrix (ECM) components that aggravate the inflammatory environment [23]. Moreover, SCI generates cellular debris and releases intracellular proteins that induce potent inflammatory stimuli.…”

Biomaterials targeting the microenvironment for spinal cord injury repair: progression and perspectives

“…SCIs are chronic and permanent injuries mainly caused by traffic accidents and unintentional falls that typically lead to compromised behavior, dysfunction, impairment, and a multitude of comorbidities ( Wang et al, 2022 ). SCI is a major central nervous system (CNS) injury that represents a significant clinical challenge ( Yuan et al, 2021 ).…”

Mesenchymal stem cells in the treatment of spinal cord injury: Mechanisms, current advances and future challenges

“…Spinal cord injury (SCI) is the most serious complication of spinal injury and usually results in transient or permanent loss of sensory, motor, and autonomic nerves below the level of injury (1). The overall global incidence of SCI is 10.5 per 100,000 persons (2). Although 94% of patients with acute traumatic SCI survive treatment, survival is greatly reduced due to post-injury complications (3).…”