MICROBIAL ANTIGENS ASSOCIATED WITH SPECIFIC ADHERENCE

革兰氏阳性菌，主要是链球菌和放线菌， 口腔微生物定植，随后牙菌斑形成， 牙龈发炎 这些生物学事件，代表了 龋齿和牙周病的发展步骤，取决于 特定的粘合性能，这是常见的一些口腔 细菌 一种这样的相互作用是细菌粘附到 获得性表膜，启动牙齿定植的相互作用 草绿色链球菌感染 此前的大量研究表明， 这一过程涉及唾液酸反应性凝集素活性， 活性还介导细菌与各种宿主细胞的粘附， 红细胞 戈登链球菌查利斯的凝集素活性具有 现在与一种特定的细菌细胞表面抗原有关。 这 涉及菌株查利斯与自发菌株的抗原比较 特别缺乏血凝活性的突变体。 越过 免疫电泳显示，天然抗原存在于提取物中， 在非粘附突变体的提取物中不存在的亲本菌株。 的 纯化抗原由蛋白质和碳水化合物组成， 菌毛形态学基于标记细胞的外观， 针对纯化抗原制备的单特异性抗体。 值得注意的是，该抗体的Fab片段抑制凝集素介导的 细菌血凝，从而将唾液酸结合 凝集素活性与特定的细菌细胞表面结构有关。 链球菌细胞壁多糖也可能在 口腔微生物定植，因为这些分子被 对其他细菌的凝集素。 结构、免疫化学和遗传学研究 这些链球菌多糖正在进行更清楚地定义 免疫和凝集素识别的决定因素。 洞察力 关于各种口腔微生物粘合剂的分子基础 这种相互作用很可能为控制牙菌斑提供了新的途径 相关疾病。

Gram positive bacteria, primarily streptococci and actinomyces, initiate oral microbial colonization, subsequent dental plaque formation and gingival inflammation. These biological events, which represent essential steps in the development of caries and periodontal diseases, depend on specific adhesive properties, that are common to a number of oral bacteria. One such interaction is the adhesion of bacteria to the acquired pellicle, an interaction that initiates the colonization of teeth by viridans streptococci. Extensive previous studies have shown that this process involves a sialic acid reactive lectin activity and that this activity also mediates bacterial adhesions to various host cells including erythrocytes. The lectin activity of Streptococcus gordonii Challis has now been associated with a specific bacterial cell surface antigen. This involved the antigenic comparison of strain Challis with a spontaneous mutant that specifically lacked hemagglutinating activity. Crossed immunoelectrophoresis revealed a native antigen present in extracts of the parent strain that was absent in extracts of the nonadherent mutant. The purified antigen was composed of both protein and carbohydrate and had a fimbrial morphology based on the appearance of cells labeled with monospecific antibody prepared against the purified antigen. Significantly, Fab fragments of this antibody inhibited lectin-mediated bacterial hemagglutination, thereby associating the sialic acid binding lectin activity with a specific bacterial cell surface structure. Streptococcal cell wall polysaccharides may also play an essential role in oral microbial colonization since these molecules are recognized by lectins on other bacteria. Structural, immunochemical and genetic studies of these streptococcal polysaccharides are underway to more clearly define the determinants of immunological and lectin recognition. Insight concerning the molecular basis of various oral microbial adhesive interactions may well suggest novel approaches for the control of plaque related diseases.