免疫调控分子CEACAM-1与TIM-3联合调控脓毒症患者单核细胞功能的研究

Monocyte de-activation has been linked to immune paralysis and high mortality in patients with severe sepsis. Our previous studies have found that the expression of immune regulatory molecules CEACAM-1 and TIM-3 were involved in altered monocyte function in septic patients, however, the specific mechanism is unclear. And we found a “drift” from CEACAM-1/TIM-3 single positive cells to CEACAM -1/TIM-3 double positive cells as with progression of sepsis, suggesting that two molecules may have a synergistic effect. In this study we plan to classify monocytes by marking CEACAM -1/TIM-3 and analyze the relationship with disease severity. And we would systemically investigate the different funtion of the corresponding monocyte subgroups by gene expression profiling, cytokine quantification, phagocytosis measurement and so on. And we would evaluate the effect of single or combined blockaded of CEACAM -1/TIM-3 on restoring monocyte function. Our research is aimed to explore novel target and potential for immunotherapy for patients with sepsis.

单核细胞功能失活与脓毒症患者后期的免疫麻痹状态及高死亡率密切相关。我们前期研究发现免疫调控分子CEACAM-1和TIM-3通过其表达方式的改变参与了对脓毒症患者单核细胞功能的调控，但具体机制尚不明确。同时我们发现病情更为严重的患者出现了CEACAM-1和TIM-3单阳性细胞向双阳性细胞的“漂移”，提示这两个分子可能具有协同效应。本研究中我们拟通过共标记CEACAM-1和TIM-3分子对单核细胞进行亚群分类并分析其与疾病严重程度的相关性，同时通过基因表达谱测序、细胞因子检测、吞噬功能检测等方法分别从基因和蛋白水平分析各单核细胞亚群不同的功能及相应的信号通路，并进一步在细胞和动物模型平台上评估单独或联合阻断CEACAM-1和TIM-3通路对恢复单核细胞功能的效果，为脓毒症患者的免疫治疗提供新的靶点和理论依据。

脓毒症患者单核细胞功能失活是导致患者后期免疫麻痹状态的重要原因并且与患者的高死亡率密切相关。本课题组基于前期研究成果，探讨了可能的机制，研究和分析了TIM-3联合其他免疫检验点分子PD-1和CEACAM-1在脓毒症患者单核细胞功能抑制中的作用。我们首先通过流式细胞术检测发现相较于健康对照组，脓毒症患者单核细胞TIM-3表达显著降低，PD-1显著升高，CEACAM1表达呈上升趋势，但无统计学差异。分析显示TIM-3及PD-1的表达差异主要集中在CD14+CD16+的单核细胞亚群。进一步的体外实验证实LPS刺激可导致单核细胞免疫检验点受体表达水平变化。最后，我们通过细胞功能实验结果证实单独阻断TIM-3/PD-1等受体分子通路均有助于恢复单核细胞的细胞因子分泌功能，然而联合阻断并不能进一步增加效果。该研究为治疗脓毒症患者单核细胞功能失活提供了一种潜在的细胞治疗方法和思路。