转基因番木瓜作为抗结核植物口服疫苗的初步研究

An Initial Study of Transgenic Carica papaya Used as a Kind of Vaccine for Anti-Tuberculosis

转基因植物疫苗的研制 ,可改变传统的疫苗接种方式和接种手段 ,大大降低疫苗的生产成本 ,具有广阔的应用前景。结核病的泛滥使抗结核的免疫预防急需开发新型的疫苗 ,研制抗结核的转基因植物疫苗具有重大的理论和实践意义。本文对具有良好免疫原性的结核杆菌分泌蛋白ESAT 6基因 ,进行了修饰改造 ,构建了带潮霉素选择抗性基因的植物表达载体和根癌农杆菌工程菌 ;采用叶盘法转化热带水果番木瓜 ,获得了 13株抗性植株 ,通过PCR、Southernblot和RNAdotblot分子检测 ,确认了 4株为转基因植株。番木瓜ESAT 6转基因植株的获得 ,为进一步的结核病植物口服疫苗的免疫研究和新型抗结核疫苗的研制与开发奠定了基础。

Oral vaccines produced by transgenic plants would ch ange traditional means of production and inoculation of vaccines,and the cost of vaccine production would be reduced greatly.The epidemic of tuberculosis makes it necessary that the new and more effective vaccines for immunoprophylaxis of a nti- tuberculosis should be developed.Consequently,it is very significant to develop transgenic plant vaccines.In the report,ESAT-6 gene was modified by PC R,the Kozak sequence was placed upstream of the start codon of ESAT-6 gene and KDEL sequence was added to the end of the gene.The modified gene was integrated into a binary vector pBI121.Then ESAT-6 gene with 35S promoter and NOS terminat or was excised from pBI121/E-6 to construct plant expression plasmid with pCAMB IA1300. The plant expression plasmid pCAMBIA1300/E-6,which contains hygromycin photransferase gene (HYT)as selection marker,was transferred into Agrobacerium tumefaciens EHA105. BF Papaya's BFQ leaves were infected with Agrobace rium tumeaciens pCAMBIA1300/E-6/EHA105,and calli were screened on medium cont aining hygromycin.15 hygromycin-resistant plants were regenerated through somat ic embryogenesis from embryogenic calli,7 of which transgenic plants were identi fied by PCR,and ESAT-6 gene had been integrated into genomes of 4 transgenic pa payas by Southern blot analysis.ESAT-6 gene expression in 4 transgenic plants w as further analysised by RNA dot blot.These transgenic plants will provide new m aterial for the development of edible vaccines for anti- tuberculosis .