免疫基因治疗是当前肿瘤研究领域的研究热点，发展新型基因疫苗载体是肿瘤免疫基因治疗研究的重要课题。β-葡聚糖可通过Detin-1受体靶向抗原呈递细胞，还具有免疫增强作用。前期研究中，我们采用肝素偶联小分子量聚乙烯亚胺（PEI），首次设计、制备了一种可降解、毒性低、转染效率高的新型肝素-PEI（HPEI）非病毒基因载体(Gou ML,et al.ACS Nano 2010;IF=9.85)。进一步，我们通过化学法处理酵母提取了主要成分为β-葡聚糖的囊状酵母壳（YS），然后采用YS包裹HPEI，设计了一种新型可降解HPEI-YS靶向基因疫苗传输载体。目前，我们已制备了HPEI-YS载体，初步实验发现HPEI-YS介导的模式肿瘤基因疫苗能显著抑制肿瘤生长。下一步，我们将深入研究HPEI-YS增强肿瘤基因疫苗疗效的作用及机理，以探索增强肿瘤基因疫苗疗效的新方法，为设计新型肿瘤基因疫苗载体提供新思路。

Developing novel DNA vaccine delivery system is an interesting topic in the field of immune gene therapy, which is one of the reseach focuses of cancer research. β-glucan can target antigen presentation cells (APCs) via its receptor: Dectin-1, and can also strengthen the immune system. In recent work, we conjugated low-molecular weight polyethyleneimine (PEI) by heparin, creating a novel hearpin-PEI (HPEI) non-viral gene carrier with degrability, low cytotoxity and high transfection efficiency (Gou ML, et al. ACS Nano 2010;IF=9.85). We also prepared yeast shell (YS) with main components of β-glucan by chemical extraction of yeast, and used YS to encapsulate HPEI, designing a novel biodegradable HPEI-YS DNA vaccine delivery system with capacity to target APCs. Now, we have prepared HPEI-YS, and found that HPEI-YS mediated model cancer DNA vaccine can significantly inhibit the growth of cancer in vivo. In future work, we will deeply study the effect and machanism of HPEI-YS enhancing therapeutic effects of cancer DNA vaccine, with the goal of finding new method to enhance the therapuetic effect of cancer DNA vaccine and providing new idea for designing novel cancer DNA vaccine delivery systems.