IGG SUBCLASS RESPONSE TO A ACTINOMYCETEMCOMITANS

局限性青少年牙周炎(LJP)的发病风险 在不同的EC群体中差异很大，黑人是 患这种疾病的可能性大约是白人的15倍 疾病。LJP也倾向于在家庭内部聚集，这表明 这种易感性可能是由基因决定的。然而，到目前为止， LJP的遗传标记尚未确定。黑人LJP 受试者对A. 放线菌角化放线菌是本病的病原体， 相当大比例的免疫球蛋白应答由以下成分组成 IgG2亚类抗体。这些免疫球蛋白G2的有效性 宿主防御中的抗体还没有定义。从基因上讲- Ig G Fc受体定义的多态性(Fc-lambda-R)可以 显著影响人免疫球蛋白亚类的受体亲和力， 尤其是IgG2。这项提议的一个主要目标是 评价Fc-lambda-R基因多态性与 抗A. 伴生放线菌与LJP风险的种族差异。 此外，我们将检查初始的免疫球蛋白亚类对 疾病发作后的这种有机体。具体来说，我们 建议： L。确定等位基因频率的变异是否 Fc-lambda-R基因多态性在不同性别的UP人群中存在 种族背景。 2.明确Fc-lambda-R基因多态性对 LJP血清中Ig G亚类抗体促进免疫功能的研究 伴生放线菌的优化作用。 3.评估免疫球蛋白亚类对A. 伴生放线菌，出现在早期阶段 从牙周健康状态过渡到LJP状态。 4.比较不同种族LJP的免疫球蛋白亚类反应 受试者对伴生放线菌的关键抗原的研究。 从拟议研究中得出的信息将提供 深入了解Fc-lambda-R多态在定义 LJP在不同种族之间的风险，以及在监管 伴放线放线菌免疫球蛋白亚类抗体的特性 在LJP受试者血清中。此外，这些研究将加强我们的 了解免疫球蛋白对A. LJP发病后的伴生放线菌以及 猪免疫球蛋白免疫球蛋白应答的质和/或量的变化 不同种族的LJP受制于这种生物。

Risk for development of localized juvenile periodontitis (LJP) varies markedly among different e c groups, with blacks being roughly 15 times more likely than Caucasians to develop this disease. LJP also tends to aggregate within families, suggesting that susceptibility may be genetically-defined. To date, however, a genetic marker for LJP has not been identified. Black LJP subjects mount a strong IgG response toward A. actinomycetemcornitans, the etiologic agent of this disease, a significant proportion of the IgG response being comprised of antibodies of the IgG2 subclass. The effectiveness of these IgG2 antibodies in host defense has not been defined. Genetically- defined polymorphism of IgG Fc receptors (Fc-lambda-R) can markedly affect receptor affinity for human IgG subclasses, particularly IgG2. A principal objective of this proposal is to evaluate the relationship between Fc-lambda-R polymorphism, opsonic activities of IgG subclass antibodies to A. actinomycetemcomitans, and ethnic variations in risk for LJP. Moreover, we will examine the initial IgG subclass responses to this organism following the onset of disease. Specifically, we propose to: l. Determine if variations in the frequency of allelic polymorphism of Fc-lambda-R exist among UP subjects of diverse ethnic background. 2. Define the influence of Fc-lambda-R polymorphism upon the effectiveness of IgG subclass antibodies in LJP sera in promoting opsonization of A. actinomycetemcomitans. 3. Assess temporal changes in the IgG subclass responses to A. actinomycetemcomitans which occur during the early stages of transition from a periodontally healthy state to one of LJP. 4. Compare the IgG subclass responses of ethnically diverse LJP subjects to key antigens of A. actinomycetemcomitans. The information derived from the proposed studies will provide insight into the role of Fc-lambda-R polymorphism in defining risk for LJP among various ethnic groups, and in regulating the properties of IgG subclass antibodies to A. actinomycetemcomitans in sera of LJP subjects. Moreover, these studies will enhance our understanding of the dynamics of the IgG response to A. actinomycetemcomitans following the onset of LJP, as well as of qualitative and/or quantitative variations in the IgG response of ethnically diverse LJP subjects to this organism.