几种天然环二核苷酸作为人体佐剂作用潜力的比较

Comparison of potential effects of natural cyclic dinucleotides as adjuvant of vaccines for human use

目的对几种天然环二核苷酸(cyclic dinucleotide,CDN)作为人体佐剂作用的潜力进行比较。方法以相同剂量的CDN(c-di-GMP、c-di-AMP、3′3′cGAMP和2′3′cGAMP)同人体来源的单核细胞白血病细胞(human monocytic leukaemia cells,THP-1)共孵育,同时将CDN(c-di-GMP和2′3′cGAMP)与脂质体混合后同THP-1细胞共孵育,刺激5 h后,收集细胞及培养液,采用实时定量PCR及ELISA法检测IFNβ基因及蛋白的表达水平,同时检测脂质体对不同类型CDN刺激作用的影响。结果 4种CDN均能有效刺激THP-1细胞IFNβ基因及蛋白表达水平的提高,且对人体细胞作用从强到弱依次为2′3′cGAMP、3′3′cGAMP、c-di-AMP和c-di-GMP,各自之间差异有统计学意义(P <0. 01)。脂质体能显著增强典型和非典型CDN对THP-1细胞的刺激作用,差异有统计学意义(P <0. 01)。结论 4种天然CDN对人体均具有潜在的佐剂效应,从作用强度看,2′3′cGAMP是最优选择,同时脂质体能增强CDN的这种效应,为将来进一步对CDN类化合物的佐剂作用的研究奠定基础。

Objective To compare the potential of several natural cyclic dinucleotides(CDN)as adjuvant of vaccines for human use.Methods THP-1 cells were co-incubated with various CDNs(c-di-GMP,c-di-AMP,3′3′cGAMP and 2′3′cGAMP) at an equal concentration in vitro.Meanwhile,c-di-GMP and 2′ 3′ cGAMP were mixed with liposome and coincubated with THP-1 cells.After incubation for 5 h,the cell pellets and supernatant were collected and determined for expression of IFNβ gene and protein by real-time quantitative polymerase chain reaction(q PCR)and ELISA respectively.The influence of liposome on stimulatory effect of various CDNs was evaluated.Results The CDNs enhanced the expressions of IFNβ gene and protein in THP-1 cells.In the turn of effect intensities,the CDNs were 2′3′cGAMP,3′3′cGAMP,c-di-AMP and c-di-GMP,with significant differences(P< 0.01).Liposomes enhanced the effects of both noncanonical CDN and the canonical CDN on THP-1 cells significantly(P< 0.01).Conclusion All the natural CDNs showed potential adjuvanticity to vaccines for human use.Specifically,2′ 3′ cGAMP was the optimal choice in terms of effect intensity,and liposome enhanced the effect.It laid a foundation of further study on the adjuvanticity of CDNs and their analogues.