Preliminary immunological evaluation of Mycobacterium tuberculosis multicomponent protein vaccine candidates EPDPA015f and EPDPA015m
10.3760/cma.j.cn112309-20221025-00350
- VernacularTitle:结核分枝杆菌多组分蛋白候选疫苗EPDPA015f和EPDPA015m的免疫作用初步评价
- Author:
Ruihuan WANG
1
;
Xueting FAN
;
Chengyu QIAN
;
Bin CAO
;
Jinjie YU
;
Machao LI
;
Guilian LI
;
Xiuqin ZHAO
;
Xiuli LUAN
;
Haican LIU
;
Kanglin WAN
Author Information
1. 中国疾病预防控制中心传染病预防控制所，传染病预防控制国家重点实验室，北京 102206
- Keywords:
Mycobacterium tuberculosis;
Multicomponent protein;
T-cell epitope;
Vaccine;
Immunological evaluation
- From:
Chinese Journal of Microbiology and Immunology
2023;43(4):294-303
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To preliminarily evaluate the immunogenicity and efficacy of two novel tuberculosis vaccine candidates (a fusion multicomponent protein EPDPA015f and a mixed multicomponent protein EPDPA015m) and to provide a new antigen combination for the development of tuberculosis vaccines.Methods:Recombinant plasmids for the expression of EPDPA015f and EPDPA015m proteins were constructed. Six-week-old BALB/c mice were immunized with EPDPA015f or EPDPA015m in combination with aluminium adjuvant (50 μg/mouse) for three times with an interval of 10 d. The mice were sacrificed 10 d after the last immunization to collect blood and spleen samples. Serum antibody titers and cytokine levels were measured by ELISA, Luminex technique and enzyme-linked immunospot assay (ELISPOT). Mycobacterial growth inhibition assay (MGIA) was used to detect the ability of mouse splenocytes to inhibit the growth of Mtb in vitro. One-way analysis of variance and t-test were used for statistical analysis. Results:Both EPDPA015f and EPDPA015m could induce the production of various cytokines and IgG antibodies at a high level. The levels of cytokines related to Th1 (IL-2, TNF-α, IFN-γ), Th2 (IL-4, IL-6, IL-10) and Th17 (IL-17) as well as other proinflammatory cytokines (GM-CSF, IL-12) were higher in the EPDPA015f group than in the adjuvant group ( P<0.05). The titer of IgG antibody induced by EPDPA015f was as high as 1∶4×10 6. The results of MGIA showed that the numbers of Mtb (lgCFU) in the PBS, adjuvant, EPDPA015f and EPDPA015m groups were 3.46±0.11, 3.51±0.06, 2.98±0.09 and 3.19±0.08, respectively. The number of colonies in the EPDPA015f group was the least as compared with that in the other three groups ( P<0.001, P<0.001, P<0.01). Conclusions:The vaccine candidate EPDPA015f could elicit more comprehensive and high-level cellular and humoral immune responses, and exhibited superior in vitro inhibitory activity against the growth of Mtb. EPDPA015f had the potential to be used as a preventive vaccine or a booster vaccine
