Functional analyzes of peripheral blood and locally infiltrated T cells in periodontitis patients.

以往的研究表明，慢性炎症牙周病变中以CD45~+T淋巴细胞为主，血清中抗牙龈卟啉单胞菌的抗体效价为lgG2。牙周炎患者的牙周炎程度与临床指标呈正相关。为了进一步研究边缘牙周炎的局部和全身免疫反应，对P.G.来源的抗原P.G.超声波提取物(P.G.S.E.)并检测炎症牙周组织中细胞因子的产生。刺激指数平均值(S.I.)25例患者血药浓度为1.63，高于健康志愿者的0.99。7例患者对S.I.2.以上的P.G.S.E.有明显的增殖反应。在5名表现出高S.I.的健康志愿者中，加入抗CD4和抗II类MHC的单抗可抑制对P.G.S.E.的增殖反应。这提示CD4T细胞在第II类MHC-res…中识别P.G.来源的抗原更曲折的方式，导致它们的扩散。流式细胞仪分析显示，在P.G.S.E.刺激下，增殖的T细胞中CD45RA、CD45RO的比例增加。为了更详细地检测CD45亚型的表达，引入了选择性剪接外显子两侧的RT-PCR方法。扩增的CD45基因表达谱显示，P.G.S.E.刺激的T细胞使含有第5外显子的单一外显子形式的CD45mRNA和CD45RO异构体的表达增加，表明CD45异构体的表达比流式细胞仪检测的更复杂。从牙周炎患者牙周组织中提取RNA，用RT-PCR法检测炎症牙周组织中细胞因子mRNA的表达。T细胞来源的细胞因子、IL-2和IL-4mRNAs在牙周炎患者牙周组织中未检测到，但从CD3激活的外周血T细胞中成功地扩增出它们的RNA。这些结果可能表明，慢性炎症牙周组织中T细胞的渗透降低了分泌这些细胞因子的能力，并丧失了局部免疫反应的调节功能。进一步的研究将是必要的，特别是为了澄清炎症牙龈中P.G.激活的T细胞产生的细胞因子。较少

Previous studies demonstrated that CD4^+CD45^+T lymphocytes predominated in chronically inflamed periodontal lesion and the serum lgG2 titer against Porphyromonas gingivalis (P.g.) exhibited corelation with clinical index in periodontitis patients. To further examine the local and general immune responses involved in marginal periodontitis, proliferative responses of peripheral blood T lymphocytes against P.g.-derived antigens, P.g. sonicate extract (P.g.S.E.) and cytokine production in inflamed periodontal tissue was examined. The average of stimulation index (S.I.) in 25 patients was 1.63, which is higher than 0.99 obtained from healthy volunteers. Seven patients showed remarked proliferative responses to P.g.S.E.with over S.I.2. In the 5 healthy volunteers who exhibited high S.I., proliferative response to P.g.S.E.was inhibited by the addition of anti-CD4 and anti-class II MHC monoclonal antibodies. This suggested that CD4^+T cells recognized P.g.-derived antigen in class II MHC-res … More tricted manner, resulting in their proliferation. Flow cytometric analysis showed that the proportion CD45RA^+CD45RO^+ was increased among proliferating T cells by the stimulation of P.g.S.E.. To detect CD45 isoform expression in detail, RT-PCR by the primers flanking the alternatively spliced exons was introduced. The profile of amplified CD45 mRNA revealed that P.g.S.E.-stimulated T cell increased the expression of single exon form of CD45mRNA,containing 5th exon, as well as CD45RO isoform mRNA,indicating more complicated expression of CD45 isoform than that detected by flow cytometry. Gingival biopsies from periodontitis patients, where RNA was extracted to examine the expression of cytokine mRNA in inflamed periodontium by RT-PCR.T cell-derived cytokine, IL-2 and IL-4 mRNAs were not detected in RNA from gingival biopsies althogh they were successfully amplified in RNA from CD3-activated peripheral blood T cells. These results may suggest that infiltrating T cells in chronically inflamed periodontium decrease the ability to secret those cytokines and loss the regulatory functions in local immune responses. Further investigation would be necessary particulary for clarifying cytokine production by P.g.-activated T cells in inflamed gingiva. Less