Treatment of surgical brain injury with immune tolerance induced by intrathymic injection of brain antigen / 中华创伤杂志

ABSTRACT

Objective To determine the effect of induction of immune tolerance by intrathymic injection of myelin basic protein (MBP) for treatment of surgical brain injury (SBI) in rats.Methods Twenty-four male SD rats were divided into experimental group,control group and sham group with 8 rats each,according to the random number table.SBI model was established in experimental group and control group.Thymuses were exposed and injected with MBP (experimental group) or saline (control group) respectively.Sham group received craniotomy without durotomy and thymus paracentesis.Modified neurological severity score (MNSS),cerebral edema volume,levels of peripheral blood proinflammatory cytokine interleukin (IL)-2 and anti-inflammatory cytokine IL-4,and CD4 +/CD8 + T-cell ratio were measured at postoperative 1,3,7,14 and 21 d.Results MNSS between control and experimental groups differed significantly at each time point (P ＜ 0.05).Compared to sham group,MNSS in experimental group was recovered the same value at 21 d (P ＞ 0.05),but in control group remained high over the study (P ＜ 0.05).Less cerebral edema was observed in control and experimental groups than in control group at each time point (P ＜ 0.05),but all were lower than these in sham group (P ＜ 0.05).Lower IL-2 concentrations and higher IL-4 concentrations were observed in experimental group than in control group at 3,7 and 14 d (P ＜0.05).Compared to sham group,IL-2 concentrations in experimental group and IL-4 concentrations in control group revealed no significant differences at each time point (P ＞0.05).CD4 +/CD8 + T-cell ratio between experimental group and control group revealed significant difference at 1,7 and 14 d (P ＜0.05).CD4 +/CD8 + T-cell ratio in experimental group and control group recovered to the same level in sham group at 7 and 21 d(P ＞ 0.05).Conclusion Induction of immune tolerance through intrathymic injection of MBP can reduce neurological deficit and brain edema and facilitate the recovery of function from SBI.