Regulatory effects on the functions of neutrophils by human salivary antimicrobial peptides, histatins

1.组抑素的定量测定及其性质建立了人唾液中组抑素的反相高效液相色谱法。组抑素与唾液中的高分子酸组分结合在一起。健康受试者唾液中总组抑素的平均值为28.6微米，且未观察到性别差异。组蛋白分泌的日变化无节律。唾液中的组蛋白被唾液中存在的蛋白水解酶在pH 7.0下孵育时自动降解。在分泌的唾液中，组蛋白5不是由组蛋白3.2产生的。组他汀类药物对中性粒细胞产生H_2O_2的抑制作用：中性粒细胞在纤维连接蛋白包被的培养皿上加入fMLP后产生H_2O_2，这种H_2O_2产生被组他汀类药物剂量依赖性地抑制，但不能抑制PMA诱导的H_2O_2产生。组素可通过中性粒细胞表面受体抑制H_2O_2的产生。另一方面，组他汀类药物并不能抑制其趋化和吞噬功能。这些结果表明，抗菌剂组他汀类药物持续分泌到口腔中，保护口腔粘膜免受中性粒细胞产生的活性氧的影响。

1. Quantitative determination of histatins and their characterization.The assay method for histatins in human saliva using a reversed-phase high performance liquid chromatography has been developed. The histatins have been bound to the high-molecular mass acid components in saliva. A mean value of the total histatins in whole saliva from healthy subjects was 28.6 muM and sex related differences for the histatin concentration was not observed. Diurnal changes of the histatin secretion did not show rhythms. Histatins in the saliva were autodegraded by proteolytic enzymes present in the saliva, as incubated at pH 7.0. In secreted saliva, histatin 5 was not generated from histatin 3.2. Inhibition by histatins on H_2O_2 generation from neutrophils.Neutrophils generated H_2O_2 in the addition of fMLP on the fibronectin-coated dish plate and this H_2O_2 production was inhibited by histatins dose-dependently, PMA-induced H_2O_2 generation was not inhibited by them. Histatins could inhibit the H_2O_2 generation via receptors on the neutrophils. On the other hand, histatins did not inhibit their chemotaxis and phagocytosis.These results suggest that antimicrobial histatins are secreted into the oral cavity constantly, and protect the oral mucous membrane from active oxygen generated by neutrophils.