Fine D H, Furgang D
Dental Research Center and Department of Oral Pathology and Biology, University of Medicine and Dentistry of New Jersey, New Jersey Dental School, Newark 07103, USA.
J Periodontol. 2002 Jun;73(6):616-23. doi: 10.1902/jop.2002.73.6.616.
Prior reports have suggested that the iron-binding protein lactoferrin (LF) may either kill Actinobacillus actinomycetemcomitans (Aa) or interfere with its binding to host cells. Other studies have indicated that the degree of iron saturation of LF might play a role in these interactions. However, these studies utilized strains that had lost critical attachment characteristics found in well-preserved clinical isolates of Aa. The purpose of this work was to study the effect of LF iron levels on survival and attachment of well-preserved clinical isolates of Aa.
LF containing 0%, 30%, and 100% iron saturation was tested for its ability to kill clinical isolates of Aa and to inhibit their binding to buccal epithelial cells (BECs).
Neither iron-free LF (apo-LF) nor iron-saturated LF killed Aa clinical isolates. Increasing the iron saturation of LF resulted in an increased inhibition of Aa binding to BECs (P < or =0.005). This effect was consistent for the 3 clinical isolates tested. Pretreatment of Aa with iron-saturated LF reduced binding to BECs by 58%, 61.8%, and 64.2%, respectively, for each of the 3 clinical strains tested (P < or =0.005). Pretreatment of Aa strains with apo-LF, iron alone, or bovine serum albumin had no effect on binding. Pretreatment of BECs with LF (either apo-LF or iron-containing LF) had no influence on Aa binding.
These results indicate that reduction in binding of Aa to epithelial cells is maximized by pretreatment of Aa cells with iron-saturated lactoferrin. These in vitro results suggest that patients with lactoferrin containing lowered levels of iron would be more susceptible to Aa colonization.
先前的报告表明，铁结合蛋白乳铁蛋白（LF）可能杀死伴放线放线杆菌（Aa）或干扰其与宿主细胞的结合。其他研究表明，LF的铁饱和度程度可能在这些相互作用中发挥作用。然而，这些研究使用的菌株已失去了在保存良好的Aa临床分离株中发现的关键附着特性。这项工作的目的是研究LF铁水平对保存良好的Aa临床分离株存活和附着的影响。
测试了铁饱和度为0%、30%和100%的LF杀死Aa临床分离株以及抑制其与颊上皮细胞（BEC）结合的能力。
无铁LF（脱铁乳铁蛋白）和铁饱和LF均未杀死Aa临床分离株。增加LF的铁饱和度导致对Aa与BEC结合的抑制作用增强（P≤0.005）。对于所测试的3株临床分离株，这种效果是一致的。用铁饱和LF预处理Aa后，对于所测试的3株临床菌株，其与BEC的结合分别减少了58%、61.8%和64.2%（P≤0.005）。用脱铁乳铁蛋白、单独的铁或牛血清白蛋白预处理Aa菌株对结合没有影响。用LF（脱铁乳铁蛋白或含铁LF）预处理BEC对Aa结合没有影响。
这些结果表明，用铁饱和乳铁蛋白预处理Aa细胞可最大程度降低Aa与上皮细胞的结合。这些体外研究结果表明，乳铁蛋白中铁含量降低的患者更容易发生Aa定植。
