Abnormality of CD4(+)CD25(+) regulatory T cells in idiopathic thrombocytopenic purpura.
OBJECTIVE
The aim of this study was to explore the profile and function of CD4(+)CD25(+) regulatory T cells (Treg cells) in idiopathic thrombocytopenic purpura (ITP) patients.


METHODS
Treg cell numbers were analyzed by flow cytometric analysis in peripheral blood mononuclear cells collected from healthy donors or patients with ITP. Quantification of cell proliferation was assayed by an enzyme-linked immunosorbent assay kit, based on the measurement of BrdU incorporation during DNA synthesis.


RESULTS
The percentage of Treg cells was significantly decreased in ITP patients in active and non-remission state(5.79 +/- 1.22%) when compared with the patients in remission(11.63 +/- 4.56%) and to healthy subjects(12.68 +/- 3.59%). The suppressive activity of Treg cells in ITP patients was also found to be impaired.


CONCLUSIONS
These results suggest that decreased number and function of Treg cells might be one of mechanisms that cause immune regulation dysfunction in ITP.
Liu
Bin
B
State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China.
Zhao
Hui
H
Poon
Man-Chiu
MC
Han
Zhibo
Z
Gu
Dongsheng
D
Xu
Maoqiang
M
Jia
Hairong
H
Yang
Renchi
R
Han
Zhong Chao
ZC
D000293:Adolescent; D000328:Adult; D015704:CD4 Antigens / Q000032:analysis; D002455:Cell Division; D002478:Cells, Cultured / Q000276:immunology; D004261:DNA Replication; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D053645:Interleukin-2 Receptor alpha Subunit / Q000032:analysis; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000627:therapeutic use; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D012074:Remission Induction; D013103:Spherocytosis, Hereditary / Q000276:immunology / Q000473:pathology; D013154:Spleen / Q000276:immunology / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000737:chemistry / Q000276:immunology / Q000473:pathology*
D015704:CD4 Antigens; D007166:Immunosuppressive Agents; D053645:Interleukin-2 Receptor alpha Subunit; D011239:Prednisolone