For a long time, many types of vaccines have been useful for the prophylaxis of many infectious diseases. Thus far, many adjuvants that enhance the effects of vaccines have been explored. However, very few adjuvants are being used for humans worldwide. In this study, we investigated the adjuvant activity of various substances, and found citrulline to have high potential as an adjuvant. Citrulline is a type of amino acid present in the body of many organisms. A number of biological activities of citrulline have been reported; however, no adjuvant activity has been reported thus far. Aluminum salts, which are commonly used as adjuvants are not water soluble; therefore, some difficulties are encountered while using them as vaccine adjuvants. Citrulline is easy to use because of its water solubility. In this study, we showed for the first time the adjuvant activity of citrulline by using viral antigens and amyloid β peptide. Water-soluble citrulline, which is present in our body, is a potential adjuvant candidate.

中文翻译：

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瓜氨酸作为疫苗的新型佐剂候选物。

长期以来，许多类型的疫苗已用于预防许多传染病。迄今为止，已经探索了许多增强疫苗作用的佐剂。然而，全世界几乎没有佐剂用于人类。在这项研究中，我们调查了各种物质的佐剂活性，发现瓜氨酸具有很高的佐剂潜力。瓜氨酸是存在于许多生物体内的一种氨基酸。据报道瓜氨酸有许多生物学活性。然而，迄今为止尚未报道佐剂活性。通常用作佐剂的铝盐不溶于水；因此，将它们用作疫苗佐剂时会遇到一些困难。瓜氨酸由于其水溶性而易于使用。在这个研究中，我们首次使用病毒抗原和β淀粉样蛋白肽显示了瓜氨酸的佐剂活性。存在于我们体内的水溶性瓜氨酸是潜在的佐剂候选物。