疫苗是人类治疗和预防疾病最有效的手段。理想的疫苗应该具有以下特性：（一）一次接种即获得长效免疫保护；（二）在较高温度下性质稳定，便于贮存和运输；（三）接种价廉，大多数人能够接受［１］。传统的疫苗一般需多次反复接种，经历时间长，疫苗需低温储存，使其辍种率较? Vaccines are the most effective means of human treatment and prevention of disease. An ideal vaccine should have the following characteristics: (i) long-term immunoprotection is obtained upon one vaccination; (ii) it is stable at higher temperatures and is convenient for storage and transport; (iii) inexpensive for vaccination and most people are able to accept [1 ]. Traditional vaccines generally require repeated inoculation, experienced a long time, the vaccine need to be stored at low temperature, so that the rate of dropout?