中文摘要：

目的探讨侵袭性牙周炎患者外周血中CD4＋CD-25＋调节性T细胞比例及其免疫抑制功能的变化，以期加深对侵袭性牙周炎免疫调节机制的认识。方法应用流式细胞仪计数牙周健康者17例、慢性牙周炎患者17例和广泛型侵袭性牙周炎患者16例外周血中CD4＋CD-25＋调节性T细胞的比例；免疫磁珠法分离受试者外周血中CD4＋CD-25＋调节性T细胞和CD4＋CD-25＋T细胞，体外淋巴细胞混合培养法检测CD4＋CD-25＋调节性T细胞对同源CD4＋CD-25-T细胞增殖的抑制效应。结果侵袭性牙周炎患者外周血中CD4＋CD-25＋调节性T细胞占CD-4＋T细胞的比例为（9．71±4．01）％，显著低于牙周健康者[（14．72±3．51）％]和慢性牙周炎患者[（17．01±5．16）％]，差异有统计学意义（P〈0．05）；当CD4＋CD-25＋调节性T细胞与CD4＋CD-25-T细胞的比例为2：1、1：1、1：2时，侵袭性牙周炎患者CD4＋CD-25＋调节性T细胞的抑制率[分别为（31．37±5．12）％、（24．47±5．53）％及（19．36±3．58）％]较慢性牙周炎患者[分别为（54．14±8．23）％、（41．72±6．35）％及（28．21±5．31）％]和牙周健康者[分别为（58．02±9．62）％、（45．25±8．11）％及（29．56±4．23）％]显著降低（P〈0．05）。结论侵袭性牙周炎患者外周血CD-4＋CD-25＋调节性T细胞在数量上存在异常，并可能伴有抑制功能缺陷。

英文摘要：

Objective To investigate the changes of proportion and suppression function of CD-4＋ CD-25 ＋ regulatory T cells in the peripheral blood of patients with aggressive periodontitis. Methods Flow cytometric analysis was used to detect the frequency of CD-4 ＋ CD-25 ＋ regulatory T cells in the peripheral blood of 16 patients with generalized aggressive periodontitis and 17 patients with chronic periodontitis, as well as 17 periodontal healthy controls. Furthermore, CD-4 ＋ CD-25 ＋ regulatory T cells and CD-4 ＋ CD-25- T cells were separated from peripheral blood of each enrolling subject using magnetic cell sorting technology. The direct suppression effect of CD-4 ＋ CD-25 ＋ regulatory T ceils on CD-4 ＋ CD-25 - T lymphocytes proliferation was performed by the mixed lymphocytes reaction and measured by 3 H-thymidine radioactive assay. Results The patients with generalized aggressive periodontitis had a lower frequency of CD-4＋ CD-25＋regulatory T cells （9. 71 ±4. 01 ） % in the peripheral blood than periodontal healthy controls [ （ 14. 72 ± 3.51 ） % ] and chronic periodontitis patients [ （ 17.01 ±5. 16 ） % ], P 〈 0. 05. A significant decrease was found in the suppression function of CD-4 ＋CD-25 ＋ regulatory T cells from peripheral blood of patients with generalized aggressive periodontitis when co-cultured with CD-4＋ CD-25 - T lymphocytes in the proportion of 2 ： 1,1 ： 1 and 1 ： 2 as compared with chronic periodontitis patients and periodontal healthy controls （P 〈 0. 05 ）. Conclusions Diminished numbers and decreased suppression function of CD-4＋ CD-25 ＋ regulatory T cells were found in patients with generalized aggressive periodontitis.