DNA疫苗至今未能用于人类疾病的预防和治疗，其主要原因是免疫原性低。有关DNA疫苗在体内作用的细胞和分子机制知道较少，经口接种DNA疫苗在肠道黏膜局部如何进行抗原处理提呈和诱导产生适应性免疫应答的机制更不清楚。为此，本项目拟通过口服自行构建的Ag85A DNA疫苗，从与传统蛋白质抗原提呈方式不同的角度，对肠道黏膜局部APC和非APC细胞内识别双股DNA（dsDNA）疫苗的传感器分子及其信号传导途径，经此方式诱导细胞和体液免疫应答的机制进行研究，进一步深入了解影响口服 Ag85A DNA疫苗免疫原性的关键因素，为提高口服DNA疫苗的免疫原性及疫苗设计提供实验和理论依据。

DNA vaccines have not been applied clinically for prophylaxis and treatment, mainly due to the weak immunogenicity. So far there are very limited studies on molecular mechanisms of DNA vaccine and moreover, the immune mechanisms through which, oral DNA vaccine would be processed and presented to initiate an immune response in intestine mucous system remain unclear. The aim of this research is: via oral delivery of artificial Ag85A DNA vaccine, followed by, from different aspects of antigen presentation, to investigate sensor molecules, which will recognize dsDNA vaccine inside the APC or non APC in intestine mucous system and the way of transduction, as well as induced cellular and humeral immune responses in this way, so as to understand in depth, key factors which will affect immunogenicity of Ag85 DNA vaccine. This investigation will provide a meaningful mode of action and data for design of DNA vaccine with strong immunogenicity.