[Detection and functional analysis of CD-4+ CD-25+ regulatory T cells in the peripheral blood of patients with generalized aggressive periodontitis].

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 cells on CD-4+ CD-25- T lymphocytes proliferation was performed by the mixed lymphocytes reaction and measured by 3H-thymidine radioactive assay. RESULTS: The patients with generalized aggressive periodontitis had a lower frequency of CD4+ 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.

[Association of TNFA-308 gene polymorphisms with susceptibility to chronic periodontitis in Chinese patients].

PURPOSE: The purpose of this study was to investigate the relationship between TNFalpha-308 gene polymorphisms and susceptibility to chronic periodontitis in Chinese patients. METHODS: DNA samples with buccal swabs were collected from 63 severe CP patients, 103 initial to moderate CP patients, and 80 healthy controls in Chinese Han nationality. The TNFA-308 gene polymorphisms were analyzed with PCR-RFLP. The data were analyzed by X(2) test using SPSS10.0. RESULTS: There were no significant genotype distribution differences of TNFA-308 between either two of the three subject groups. CONCLUSION: Further study was needed since we did not find the relationship between TNFA-308 gene polymorphism and periodontitis in this present study.

[Bioassay of the soluble human tumor necrosis factor receptor I recombinant plasmid expression in vitro].

OBJECTIVE: To detect the expression of recombinant plasmid PcDNA3.1-sTNFRI in vitro and evaluate the bioactivity of expressed sTNFRI. METHODS: CHO cells were transfected with recombinant plasmid PcDNA3.1-sTNFRI by liposome. sTNFRI in cell culture supernatant was detected by ELISA and sTNFRI blockage of TNF-alpha cytotoxicity in L929 cells evaluated by MTT assay. RESULTS: The expression of sTNFRI in transfected cell culture supernatant was higher than control groups (P < 0.001). The expressed sTNFRI could significantly neutralize TNF-alpha cytotoxicity in L929 cells. CONCLUSIONS: These results showed that the recombinant plasmid PcDNA3.1-sTNFRI can be expressed in mammalian cells and the recombinant sTNFRI has biological function.