title: A survey on the distribution of healthy people with different anti-tumour ability.
abstract: BACKGROUND
  The aim of the study was to explore the distribution of healthy people with different anti-tumour ability.
  
  
  METHODS
  Leukocytes were separated by the Ficoll-Hypaque density gradient centrifugal method. Then they were mixed with A549, MCF-7 and Hela cells at different ratios. The survival rate for target cells was observed and counted by Fluoroskan. Immune function for 200 healthy people was analysed by flow cytometry.
  
  
  RESULTS
  The results obtained by confocal microscopy revealed that human blood leukocytes possessed direct anti-tumour activity. The survival rate for tumour cells was the lowest in the condition of 20:1 ratio of effector cells to target cells. We speculated that in 200 healthy people the leukocyte capacity for killing MCF-7 cells is stronger than the leukocyte capacity for killing A549 cells and Hela cells. We also found that the distribution for 200 healthy people with different anti-tumour ability was different for different tumour cells. The number of healthy people with the strongest anti-tumour ability was highest when the target cells were MCF-7 cells. Moreover, the survival of A549, MCF-7 and Hela cells was correlated with T, B and NK lymphocytes.
  
  
  CONCLUSIONS
  From the above, we can select healthy individuals with strong anti-tumour ability as anti-tumour donors according to their distribution with different anti-tumour ability, which opened up a new direction for fighting human cancer.
authors.affiliation: Department of Clinical Biochemistry, Chinese PLA General Hospital, China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Gao
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Xu
authors.forename: Zhennan
authors.initials: Z
authors.lastname: Dong
authors.forename: Chaoguang
authors.initials: C
authors.lastname: Jiang
authors.forename: Jin
authors.initials: J
authors.lastname: Gao
authors.forename: Jinchuan
authors.initials: J
authors.lastname: Hu
authors.forename: Junhao
authors.initials: J
authors.lastname: Gui
authors.forename: Haibao
authors.initials: H
authors.lastname: Wang
authors.forename: Yaping
authors.initials: Y
authors.lastname: Tian