Liu Xun, Peng Jinxiu, Hu Lina, Luo Yanping, Niu Hongxia, Bai Chunxiang, Wang Qian, Li Fei, Yu Hongjuan, Wang Bingxiang, Chen Huiyu, Guo Ming, Zhu Bingdong
a Gansu Provincial Key Laboratory of Evidence Based Medicine and Clinical Translation & Lanzhou Center for Tuberculosis Research, School of Basic Medical Sciences, Lanzhou University , Lanzhou , China.
b Institute of Pathogen Biology, School of Basic Medical Sciences, Lanzhou University , Lanzhou , China.
Hum Vaccin Immunother. 2016 Jul 2;12(7):1670-7. doi: 10.1080/21645515.2016.1141159. Epub 2016 Feb 22.
To develop an effective subunit vaccine which could target tubercle bacilli with different metabolic states and provide effective protective immunity, we fused antigens ESAT6, Ag85B, peptide 190-198 of MPT64, and Mtb8.4 mainly expressed by proliferating bacteria and latency-associated antigen Rv2626c together to construct a multistage protein ESAT6-Ag85B-MPT64(190-198)-Mtb8.4-Rv2626c (LT70 for short) with the molecular weight of 70 kDa. The human T-cell responses to LT70 and other antigens were analyzed. The immune responses of LT70 in the adjuvant of DDA and Poly I:C and its protective efficacy against Mycobacterium tuberculosis (M. tuberculosis) infection in C57BL/6 mice were evaluated. The results showed that LT70 was stably produced in Escherichia coli and could be purified by successive salting-out and chromatography. LT70 could be strongly recognized by human T cells from TB patients and persons who are supposed latently infected with M. tuberculosis. The subunit vaccine LT70 generated strong antigen-specific humoral and cell-mediated immunity, and induced higher protective efficacy (5.41±0.37 Log10 CFU in lung) than traditional vaccine Bacillus Calmette-Guerin (6.01±0.33 Log10 CFU) and PBS control (6.53±0.26 Log10 CFU) at 30 weeks post vaccination (10 weeks post-challenge) against M. tuberculosis infection (p < 0.05). These findings suggested that LT70 would be a promising subunit vaccine candidate against M. tuberculosis infection.
为研发一种能靶向不同代谢状态结核杆菌并提供有效保护性免疫的高效亚单位疫苗，我们将主要由增殖细菌表达的抗原ESAT6、Ag85B、MPT64的190 - 198肽段、Mtb8.4和潜伏相关抗原Rv2626c融合在一起，构建了一种分子量为70 kDa的多阶段蛋白ESAT6 - Ag85B - MPT64(190 - 198) - Mtb8.4 - Rv2626c（简称LT70）。分析了人T细胞对LT70及其他抗原的反应。评估了LT70在DDA和Poly I:C佐剂中的免疫反应及其对C57BL/6小鼠结核分枝杆菌感染的保护效果。结果显示，LT70能在大肠杆菌中稳定表达，可通过连续盐析和层析进行纯化。LT70能被结核病患者以及疑似潜伏感染结核分枝杆菌者的人T细胞强烈识别。亚单位疫苗LT70产生了强烈的抗原特异性体液免疫和细胞介导免疫，在接种疫苗后30周（攻击后10周）对结核分枝杆菌感染的保护效果（肺中5.41±0.37 Log10 CFU）高于传统疫苗卡介苗（6.01±0.33 Log10 CFU）和PBS对照组（6.53±0.26 Log10 CFU）（p < 0.05）。这些发现表明，LT70有望成为一种抗结核分枝杆菌感染的亚单位疫苗候选物。
