title: [Inhibition of lipopolysaccharide-induced myeloid-derived suppressor cells in the proliferation of spleen T lymphocytes].
abstract: OBJECTIVE
  To explore the effects of lipopolysaccharide (LPS)-induced myeloid-derived suppressor cells (MDSCs) on the proliferation of spleen T lymphocytes.
  
  
  METHODS
  BALB/c mice were randomly divided into two groups: LPS group and normal control group. They were injected intraperitoneally with LPS and normal saline solution respectively. MDSCs were separated with CD11b immunomagnetic beads from the spleen extract of mice. The morphological characteristics of MDCSs were observed by Wright-Giemsa staining and the characteristic molecules on cell surface identified by flow cytometry. And the effects of MDSCs on the in vitro proliferation of T cells were determined by methyl-thiazolyl-tetrazolium bromide (MTT).
  
  
  RESULTS
  The proportion of MDSCs in the spleen of the LPS group was much more than that of the normal control group (27.4% ± 6.6% vs 5.1% ± 3.8%; t = 5.06, P = 0.007). CD11b(+)Gr-1(+)MDSCs could be separated by CD11b immunomagnetic beads from the spleen of mice injected with LPS at a high purity of 84.0% ± 4.2%. MTT method showed that the proliferation of T cells decreased significantly after a co-cultivation with CD11b(+)MDSCs versus the control group. And it was positively correlated with the number of MDSCs (F = 46.26, P = 0.000).
  
  
  CONCLUSIONS
  A high purity of LPS-induced myeloid-derived suppressor cells may be separated with CD11b immunomagnetic beads. And it has dose-dependent inhibitory effects on the proliferation of the spleen T lymphocytes.
authors.affiliation: Department of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China.
authors.forename: Yan-ni
authors.initials: YN
authors.lastname: Zheng
authors.forename: Hua-peng
authors.initials: HP
authors.lastname: Yu
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.forename: Huo-jin
authors.initials: HJ
authors.lastname: Deng
authors.forename: Hui-zhen
authors.initials: HZ
authors.lastname: Fan
authors.forename: Yu-xin
authors.initials: YX
authors.lastname: Gong
authors.forename: Jun-fang
authors.initials: JF
authors.lastname: Liu
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D018920:Coculture Techniques; D008070:Lipopolysaccharides / Q000009:adverse effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D022423:Myeloid Cells / Q000166:cytology / Q000187:drug effects*; D013154:Spleen / Q000166:cytology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects*
chemical_list: D008070:Lipopolysaccharides