Basic research for applying human lactoferrin to periodontal treatments

1. 龈沟液（GCF）和唾液中的人乳铁蛋白（hLf）我们测定了15个龈沟液样本和7个唾液样本的hLf水平，结果表明龈沟液中的hLf水平显著高于唾液（平均hLf水平：龈沟液226 μg/ml，唾液20μg/ml）。兔抗hLf抗体免疫荧光染色显示荧光区与结石区一致。粉状样品是用一个装有圆形燃烧器的电动机驱动系统从提取的根中制备的。采集标本，根据位置分为三组：第一层、第二层和第三层（从牙根表面到牙髓腔）。有结石区域的第一层检测到的hLf水平明显高于无结石区域的第一层。hLf和内毒素水平从第1 ~第3蛋鸡下降。4.我们对19名受试者的龈上牙菌斑和龈下牙菌斑进行了检测，结果显示龈上牙菌斑和龈下牙菌斑中的半胱氨酸水平无显著差异，但呈显著相关（0.609,p<0.01）。hLf对A.放线菌侵染的THP-1细胞sldh活性、DNA片段化和TNF-α产生的影响在添加hLf后降低。这些结果表明，中性粒细胞释放的hLf与LPS结合，抑制LPS对宿主细胞的免疫生物学作用，从而起到保护宿主的作用。

1. Human lactoferrin (hLf) in gingival crevicular fluid (GCF) and salivaWe measured hLf levels in 15 GCF samples and 7 saliva samples, showing that hLf levels in GCF were significantly higher than in saliva (mean hLf levels; 226 μg/ml in GCF and 20μg/ml in saliva).2. Distribution of hLf on periodontally-diseased dental rootThe area displaying fluorescence was in agreement with the area with calculus after immunofluorescence staining with rabbit anti-hLf antibody. Powdery samples were prepared from extracted roots with a round bur-equipped electric motor-driven system. The samples were collected and partitioned into three groups on the basis of location: Layers I, II and III (from the root surface to the pulp cavity). Significantly higher hLf levels were detected in Layer I from the area with calculus in comparison to Layer I from the area without calculus. hLf and endotoxin levels decreased from Layer I to Layer III.3. hLf levels in supra- and subgingival dental plaqueWe measured hLf levels in supra- and subgingival dental plaque from 19 subjects, showing that hLf levels in supra- and subgingival dental plaque were not significantly different, while the levels were significantly correlated (0.609, p<0.01).4. Effect of hLf on A. actinomycetemcomitans-infected THP-1 cellsLDH activity, DNA fragmentation and TNF-α production in the infected THP-1 cells were reduced upon addition of hLf. These findings suggested that hLf released by neutrophils is bound to LPS leading to inhibition of the immunobiological effects of LPS to host cells, which results in host protection.