Tokyo University of Pharmacy and Life Sciences Hachioji Japan.
FEBS Open Bio. 2019 Mar 15;9(4):791-800. doi: 10.1002/2211-5463.12615. eCollection 2019 Apr.
Melanin-producing and are highly invasive and can suppress or escape the immune system of the host. Since non-melanin-producing strains do not affect the immune system, melanin may play a role in immune system suppression. Artificial melanin synthesized using conventional methods is insoluble, making structural and functional analysis of this chemical difficult. In this study, we describe a melanin solubilization method based on polymerization of homogentisic acid (solubilizing component) and an equivalent amount of L-DOPA in the presence of laccase. In addition, we investigated the effect of melanin on the immune system. Homogentisic acid and L-DOPA mixed melanin (HALD), the synthetic solubilized melanin, did not exert a cytotoxic effect on mouse macrophages. HALD suppressed cytokine and reactive oxygen species production by macrophages when they were stimulated by fungal components. HALD also suppressed the phagocytosis of fungal components by macrophages. These results suggest that HALD can suppress the function of macrophages without causing cytotoxicity.
产黑色素的 和 高度侵袭性，可以抑制或逃避宿主的免疫系统。由于非产黑色素的菌株不会影响免疫系统，因此黑色素可能在免疫系统抑制中发挥作用。使用常规方法合成的人工黑色素不溶，使得对这种化学物质的结构和功能分析变得困难。在这项研究中，我们描述了一种基于聚合高邻苯二酚（溶解成分）和等当量 L-DOPA 在漆酶存在下的黑色素溶解方法。此外，我们研究了黑色素对免疫系统的影响。高邻苯二酚和 L-DOPA 混合黑色素（HALD），即合成的可溶解黑色素，对小鼠巨噬细胞没有细胞毒性作用。当真菌成分刺激巨噬细胞时，HALD 抑制细胞因子和活性氧的产生。HALD 还抑制了巨噬细胞对真菌成分的吞噬作用。这些结果表明，HALD 可以在不引起细胞毒性的情况下抑制巨噬细胞的功能。
