title: [Effect and mechanism of RetroNectin on the proliferation and cytotoxic activity of acute leukemia natural killer cells].
abstract: OBJECTIVE
  To explore the effects of precoated RetroNectin on the proliferation and cytotoxicity of natural killer cells (NK) from acute leukemia (AL).
  
  
  METHODS
  Mononuclear cells (MNCs) were isolated from peripheral blood of complete remission AL patients. The MNCs were cultured in vitro precoated with 50 µg/ml RetroNectin (group I), 25 µg/ml RetroNectin (group II) and by the traditional method (control group) to generate NK. The changes of growth rate, phenotypic characterization, secretion of cytokines of NK, cell cycle, apoptosis and cytotoxicity of NK were determined.
  
  
  RESULTS
  The amplification of NK in group I ((51 ± 9)×10(6)) and II ((79 ± 16) ×10(6)) were higher than that in control group ((37 ± 11)×10(6)) (both P < 0.05), and the amplification of NK in groupII was higher than that in group I (P < 0.05). There were no differences among three groups with regards to the phenotypic characterization of CD3(-)CD56(+). The secretions of interleukin 2, interleukin 12, tumor necrosis factor alpha and interferon gamma in group I and II were higher than that in control group (all P < 0.05). The expression of CD25 positive cells in groups I (38.2% ± 4.1%) and II (37.5% ± 5.1%) were higher than that in control group (24.2% ± 5.8%) (both P < 0.05). The expression of NKG2D positive cells in groups I (81.6% ± 17.9%) and II (85.7% ± 20.1%) were higher than that in control group (63.6% ± 21.9%) (both P < 0.05). The percentages of G(1) stage cells in groups I (50% ± 10%) and II (49% ± 11%) were lower than that in control group (71% ± 15%) while the percentages of S stage cells in groups I (36% ± 14%) and II (37% ± 8%) were higher than that in control group (19% ± 10%) (all P < 0.05). But no difference existed between two groups (all P > 0.05). The expression of cell cycle regulatory genes p21 and p27 were reduced in groups I and II. The percentages of apoptotic cells in groups I (10.7% ± 2.1%) and II (9.4% ± 3.1%) were lower than that in control group (29.6% ± 10.3%) (both P < 0.05). The cytotoxicity to AL cells in groups I (82% ± 21%) and II (80% ± 18%) were higher than that in control group (61% ± 14%) (both P < 0.05) at the E/T scope 20:1. But no difference existed between two groups (all P > 0.05).
  
  
  CONCLUSIONS
  The proliferation and cytotoxicity of NK cells may be boosted by precoated RetroNectin.
authors.affiliation: Department of Hematology, First Municipal Central Hospital, Tianjin 300192, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Qi
authors.initials: Q
authors.lastname: Deng
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Lie
authors.initials: L
authors.lastname: Mang
authors.forename: Yu-ming
authors.initials: YM
authors.lastname: Li
mesh_terms: D000368:Aged; D049109:Cell Proliferation / Q000187:drug effects*; D005260:Female; D005353:Fibronectins / Q000494:pharmacology*; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D007938:Leukemia / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000494:pharmacology*
chemical_list: D005353:Fibronectins; D011994:Recombinant Proteins; C545354:retronectin