Effect of umbilical cord mesenchymal stem cells on immune microenvironment and vascular reconstruction in traumatic brain injury

Objective To investigate the effects of umbilical cord mesenchymal stem cells (UCMSCs) on immune microenvironment and angiogenesis in patients with traumatic brain injury. Methods Cerebrospinal fluid (CSF) samples were divided into 4 groups, including normal group (n=6), traumatic brain injury group (n=6), traumatic brain injury+UCMSCs treatment group (n=6) and craniocerebral trauma + conventional treatment group (n=6). The CSF samples were detected by liquid chromatography-mass spectrometry, and data were collected by data independent acquisition (DIA) technology. The differential proteins were screened by bioinformatics processing, and analyzed by Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Results A total of 688 proteins were screened in CSF samples and reliably quantified. There were 38 differential proteins in the CSF of patients with traumatic brain injury after treatment with UCMSCs, including 20 up-regulated proteins and 18 down-regulated proteins. The results of GO analysis and KEGG analysis showed that the differential proteins were mainly immunoregulatory function-related proteins, angiogenesis-related proteins, and various connexins. Conclusions The main possible mechanism of UCMSCs in the treatment of traumatic brain injury is to regulate the stability of the immune microenvironment and to promote the regeneration and reconstruction of damaged brain tissue. Key words: Traumatic brain injury; Mesenchymal stem cell transplantation; Umbilical cord; Cerebral revascularization; Immune microenvironment