title: [Hypomethylation and overexpression of CD70 in CD4+ T cells of the patients with immuno-related pancytopenia].
abstract: OBJECTIVE
  To study the expression of CD70 and the methylation level of CD70 promoter in immuno-related pancytopenia（IRP）patients, and explore the role of CD70 in the pathogenesis of IRP.
  
  
  METHODS
  Thirty- five IRP patients and fifteen healthy donors were enrolled in this study. Peripheral blood mononuclear cells were isolated from venous blood by density gradient centrifugation, and CD4(+) T cells were isolated by immunomagnetic beads. The mRNA level and the percentage of CD70 of CD4(+) T cells were measured by real- time quantitative polymerase chain reaction（RT- PCR）and flow cytometry respectively. Methylation- Specific PCR（MSP）was performed to determine the methylation level of CD70 promoter.
  
  
  RESULTS
  The percentage of CD70 expression on CD4(+) T cells of untreated IRP patients［（7.46±1.51）%］was significantly higher than that of recovered ones［（5.95±1.34）%］and normal controls［（1.83 ± 0.60）%］, and that of recovered IRP patients was significantly higher than of normal controls（P<0.05）. The relative expressions of CD70 mRNA in CD4(+) T cells were 2.314（0.200-6.084）, 1.021（0.135-3.434）, 0.353（0.008-2.258）in three groups respectively. The differences among untreated IRP patients, recovered IRP patients and normal controls were significant（P<0.05）. The CD70 promoter methylation level in CD4(+) T cells of all IRP patients was significantly lower than that of normal controls （P<0.05）. The expression of CD70 positively correlated to the ratio of CD5(+) B cells（r=0.533, P<0.01）.
  
  
  CONCLUSIONS
  The overexpression of CD70 may lead to immunologic disarrangement of patients, which may play important role in the pathogenesis of IRP.
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Fu
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Huaquan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Yihao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Qi
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Jinglian
authors.initials: J
authors.lastname: Tao
authors.affiliation: Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
authors.forename: Zonghong
authors.initials: Z
authors.lastname: Shao
mesh_terms: D001402:B-Lymphocytes; D053282:CD27 Ligand; D015496:CD4-Positive T-Lymphocytes; D005434:Flow Cytometry; D006801:Humans; D010198:Pancytopenia; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D053282:CD27 Ligand; C505771:CD70 protein, human; D012333:RNA, Messenger