Decreased level of cytotoxic T lymphocyte antigen-4 (CTLA-4) in patients with acute immune thrombocytopenia (ITP).
BACKGROUND
Previously, we demonstrated the importance of T-cell immune response cDNA 7 (TIRC7) in acute immune thrombocytopenia (ITP). As the downstream molecule of TIRC7, cytotoxic T lymphocyte antigen-4 (CTLA-4) has been verified its negative regulation of acute ITP. This study aimed to investigate the exact role of CTLA-4 and its relationship with TIRC7 in acute ITP.


METHODS
37 patients with acute ITP were enrolled and received dexamethasone (40mg/day) for 4 consecutive days. Patients who had platelet counts more than 50×10(9)/L or less were defined as responders or non-responders after treatment. The plasma, protein and mRNA levels of CTLA-4 and TIRC7 were monitored by ELISA, western blot and q-PCR, respectively.


RESULTS
After high-dose dexamethasone therapy, CTLA-4 levels were significantly elevated not only in acute ITP patients (P<0.001; P<0.0001) but also in acute ITP responders (P<0.0001; P<0.0001). The levels of CTLA-4 were negatively correlated with the levels of TIRC7 before and after treatment; IFN-γ (Th1), IL-17 (Th17) and IL-22 (Th22) levels were all elevated, which were decreased after treatment not only in patients with acute ITP (P<0.01) but also in acute ITP responders (P<0.01).


CONCLUSIONS
CTLA-4 level might reflect treatment efficacy and it might be associated with the pathogenesis of acute ITP.
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Feng
F
Zhu
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China; Lab of Transplant Immunology, Xuzhou Medical College, Jiangsu Province, 221002, China.
Jianlin
J
Qiao
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Jiang
J
Cao
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Hai-Ying
HY
Sun
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China; Lab of Transplant Immunology, Xuzhou Medical College, Jiangsu Province, 221002, China.
Qing-Yun
QY
Wu
Lab of Transplant Immunology, Xuzhou Medical College, Jiangsu Province, 221002, China.
Zeng-Tian
ZT
Sun
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China; Lab of Transplant Immunology, Xuzhou Medical College, Jiangsu Province, 221002, China.
Kai
K
Zhao
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Wei
W
Sang
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Kun-Ming
KM
Qi
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China; Lab of Transplant Immunology, Xuzhou Medical College, Jiangsu Province, 221002, China.
Ling-Yu
LY
Zeng
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China.
Zhen-Yu
ZY
Li
Department of Hematology, the Affiliated Hospital of Xuzhou Medical College, Jiangsu Province, 221002, China. Electronic address: lihmd@163.com.
Kai-Lin
KL
Xu
D000293:Adolescent; D000328:Adult; D060908:CTLA-4 Antigen / Q000097:blood* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood* / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism*; D025262:Vacuolar Proton-Translocating ATPases / Q000097:blood / Q000276:immunology; D055815:Young Adult
D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C472421:TCIRG1 protein, human; D025262:Vacuolar Proton-Translocating ATPases
Acute immune thrombocytopenia; Cytotoxic T lymphocyte antigen-4; T helper cell; T-cell immune response cDNA 7