title: [Immuno-effect of plasmacytoid dendritic cells on bacteria infection induced spontaneous remission of leukemia].
abstract: OBJECTIVE
  To explore the immuno-effect of plasmacytoid dendritic cells (pDC) on bacteria infection induced spontaneous remission (SR) of leukemia.
  
  
  METHODS
  Both pDC and myeloid dendritic cells (mDC) were isolated and purified from leukemic patient with SR and healthy donor by combination of immunomagnetic beads and flow cytometry. pDC were cultured in RPMI1640 medium and stimulated with different bacteria. The T cells proliferation was detected by MTT, and cytokine production by ELISA kits.
  
  
  RESULTS
  The human bacterial pathogen Staphylococcus aureus and Pseudomonas aeruginosa stimulation for 48 h resulted in the maturation of pDC with production of high quantity of IFN-α at (15.34 ± 2.91) ng/ml and (10.38 ± 1.41) ng/ml, respectively, comparing with that of negative group at (1.36 ± 0.13) ng/ml (P<0.01). Activated pDC could promote the differentiation of naive CD4⁺ T cells to Th1 cells with secretion of IFN-γ at (2.16 ± 0.37) ng/ml and (2.73 ± 1.11) ng/ml, respectively, comparing with that of positive control at (2.55 ± 0.23) ng/ml (P > 0.05). Activated pDC showed higher T cell stimulatory capacities [proliferation index (PI) was 4.36 and 4.05, respectively] than that of non-activated pDC (PI was 1.23 and 0.13, respectively) (P < 0.01).
  
  
  CONCLUSIONS
  Staphylococcus aureus and Pseudomonas aeruginosa activated pDC may play a key role in SR of leukemia following severe infections.
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Li
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Liansheng
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Chai
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Pengyun
authors.initials: P
authors.lastname: Zeng
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Chongyang
authors.initials: C
authors.lastname: Wu
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Yue
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Bai
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Zhengdong
authors.initials: Z
authors.lastname: Hao
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Wanli
authors.initials: W
authors.lastname: Hu
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Huiling
authors.initials: H
authors.lastname: Chen
authors.affiliation: Lanzhou University Second Hospital, Lanzhou 730030, China.
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Guo
mesh_terms: D015496:CD4-Positive T-Lymphocytes; D003713:Dendritic Cells / Q000276:immunology*; D005434:Flow Cytometry; D006801:Humans; D016898:Interferon-alpha; D007938:Leukemia / Q000175:diagnosis / Q000276:immunology*; D008213:Lymphocyte Activation; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D012075:Remission, Spontaneous; D013211:Staphylococcus aureus / Q000276:immunology*
chemical_list: D016898:Interferon-alpha