title: [In vitro functions of natural killer cells in peripheral blood of patients with severe aplastic anemia].
abstract: OBJECTIVE
  To observe the in vitro killing functions of natural killer (NK) cells for K562 cells in peripheral blood of severe aplastic anemia (SAA) patients and explore the role of NK cells in the immunological pathogenesis of SAA.
  
  
  METHODS
  NK cells (CD3(-)CD56(+)CD16(+)) as effector cells were sorted from peripheral blood mononuclear cells (PBMNC) of 12 SAA patients and 10 normal controls by magnetic activated cell sorting system (MACS)from June 2013 to August 2014. K562 cells as target cells were co-cultured with the effector cells (1: 1, 1: 5, 1: 10). Using Annexin V and PI double staining markers, the apoptotic rate of K562 cells were measured by flow cytometry after culturing.
  
  
  RESULTS
  The apoptotic rate of K562 cells in SAA patients was (10.30% ± 6.08%) according to the ratio of effector-target (1: 1). And it was significantly higher than that in normal controls (6.30% ± 3.46%) (P < 0.05). The apoptotic rate of K562 cells in SAA patients were 10.30% ± 6.08%, 16.47% ± 8.29% and 25.45% ± 9.88% respectively according to the ratio of effector-target(1: 1, 5: 1, 10: 1). The higher ratio of effector-target, the higher apoptotic rate of K562 cells. There were statistic differences among three groups (P < 0.05).
  
  
  CONCLUSIONS
  There are enhanced in vitro functions of NK cells in peripheral blood of SAA patients NK cells may play an important role in abnormal immune tolerance mechanisms of SAA patients.
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Shaoxue
authors.initials: S
authors.lastname: Ding
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China. Email: florai@sina.com.
authors.forename: Rong
authors.initials: R
authors.lastname: Fu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Jiangbo
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Honglei
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Ding
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Qu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Erbao
authors.initials: E
authors.lastname: Ruan
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Guojin
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Huaquan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Guan
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Zonghong
authors.initials: Z
authors.lastname: Shao
mesh_terms: D000741:Anemia, Aplastic; D018920:Coculture Techniques; D005434:Flow Cytometry; D006801:Humans; D066298:In Vitro Techniques; D020014:K562 Cells; D007694:Killer Cells, Natural; D007963:Leukocytes, Mononuclear