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Synthesis and Evaluation of QS-7-Based Vaccine Adjuvants.

ABSTRACT: We have designed and synthesized two analogs (5 and 6) of QS-7, a natural saponin compound isolated from Quillaja saponaria (QS) Molina tree bark. The only structural difference between compound 5 and 6 is that 5 is acetylated at the 3- and 4-O positions of the quillaic acid C28 fucosyl unit while 6 is not. However, the two analogs show significantly different immunostimulant profiles. Compound 5 may potentiate a mixed Th1/Th2 (Th, T helper cells) immune response against the specific antigens while compound 6 may only induce a Th2-biased immunity. These results suggest that the 3- and/or 4-O acetyl groups of the fucosyl unit may play an important role in tuning the adjuvanticity of the QS-7 analogs, and compound 5 can serve as a structurally defined synthetic adjuvant when a mixed Th1/Th2 immune responses is desired.

SUBMITTER: Wang P

PROVIDER: S-EPMC6848976 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Synthesis and Evaluation of QS-7-Based Vaccine Adjuvants.

Wang Pengfei P Škalamera Đani Đ Sui Xianwei X Zhang Ping P Michalek Suzanne M SM

ACS infectious diseases 20190328 6

We have designed and synthesized two analogs (5 and 6) of QS-7, a natural saponin compound isolated from Quillaja saponaria (QS) Molina tree bark. The only structural difference between compound 5 and 6 is that 5 is acetylated at the 3- and 4-O positions of the quillaic acid C28 fucosyl unit while 6 is not. However, the two analogs show significantly different immunostimulant profiles. Compound 5 may potentiate a mixed Th1/Th2 (Th, T helper cells) immune response against the specific antigens wh ...[more]

PMID: 30920199

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