[The relationship between CD4+ CD25+ regulatory T cell in the peripheral blood and poor or nonresponsiveness to hepatitis B vaccine].

OBJECTIVE: To investigate CD4+ CD25+ regulatory T cell frequencies in the peripheral blood of poor or non-responsiveness to Hepatitis B vaccine, and try to understand the relationship between CD4+ CD25+ regulatory T cell and poor or non-responsiveness to Hepatitis B vaccine. METHODS: Flow cytometric analysis was employed for CD4+ CD25+ regulatory T cell frequencies in the peripheral blood of 25 cases of non-responsiveness, 30 cases of poor-responsiveness, and collected 20 cases of responsiveness as control. RESULTS: CD4+ CD25+ regulatory T cell frequencies of responsiveness was (4.32 +/- 1.21)%, poor-responsiveness was (7.01 +/- 1.06)% and non-responsiveness was (12.75 +/- 2.01)%. It was found that non and poor-responsiveness showed a high percentage of CD4+ CD25+ regulatory T cell as compared with responsiveness (t = 8.426, t = 3.289, P<0.01). CONCLUSION: The poor and non-responsiveness should be related with the increase of CD4+ CD25+ regulatory T cell and this might be considered as an important cause of poor and non-responsiveness.

[Promotion of the activity of Akt in CD8+ T cells by the crosslink of 3H3, an agonist antibody of 4-1BB].

AIM: To investigate whether 4-1BB could promote the proliferation and survival of CD8(+) T cells proliferation, and the activity of protein kinase B (Akt). METHODS: Highly purified CD8(+) T cells were separated and stimulated by CD3 antibody. The crosslink of 3H3 and the proliferation and antiapoptosis of CD8(+) T cells were examined. RESULTS: The crosslink of 3H3 promoted the proliferation and survival of CD8(+) T cells. 4-1BB induced by 3H3 promoted the phosphorylated level and kinase activity of Akt. CONCLUSION: Akt pathway might participate in 4-1BB which promoted the proliferation and survival of CD8(+) T cells induced by 3H3.