[Influence of different cyto-stimuli on immunological activity of splenic regulatory T cells in mice].
OBJECTIVE
To investigate the expression of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and intranuclear forkhead/winged helix transcription factor p3 (Foxp3) of splenic regulatory T cells (Tregs) in mice, and compare the effects of different stimuli on the immunological activity of Tregs.


METHODS
CD4+CD25+ Tregs isolated from the spleens of male BALB/c mice by magnetic beads were seeded on 96-well (1x10(5) cells/well) cell culture plates supplemented with phytohemagglutin (PHA, 20 mg/L), concanavalin A (ConA, 5 g/L) or coated with anti-CD3 (1 mg/L). After being stimulated with different stimuli for various length of time, the expressions of CTLA-4 and Foxp3 molecules of Tregs were determined. The time-dependent responses between different stimuli and CTLA-4 as well as Foxp3 were analyzed by means of flow cytometry.


RESULTS
After stimulation with PHA, the CTLA-4 expressions on surface of mice splenic Tregs and intranuclear Foxp3 molecules were unchanged (both P>0.05). In ConA-treated group, the expression of CTLA-4 was significantly up-regulated at 24 hours (P<0.01), while the CTLA-4 expression returned to the control range at 48 and 72 hours. The expression of Foxp3 was not markedly different between ConA-treated group and controls. When treated with plate-bound anti-CD3, both CTLA-4 and Foxp3 expressions were significantly up-regulated at 24, 48 and 72 hours (P<0.05 or P<0.01), especially at 24 and 48 hours (all P<0.01).


CONCLUSIONS
These data indicated that various stimuli can result in different modulatory responses of the CTLA-4 and Foxp3 expressions in mice splenic Tregs. Anti-CD3 appears to be an effective immunoregulatory signal that influences the activation of CD4+CD25+ Tregs.
Zhang
Ying
Y
Department of Gynaecology and Obstetrics, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.
Yao
Yong-ming
YM
Chang
Qing
Q
Dong
Ning
N
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D015703:Antigens, CD / Q000378:metabolism*; D017252:CD3 Complex / Q000276:immunology; D060908:CTLA-4 Antigen; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D037121:Plant Lectins / Q000494:pharmacology; D013154:Spleen / Q000166:cytology / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism
D000906:Antibodies; D015703:Antigens, CD; D017252:CD3 Complex; D060908:CTLA-4 Antigen; C556707:Ctla4 protein, mouse; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D037121:Plant Lectins; D003208:Concanavalin A