title: Nanoliposomes of L-lysine-conjugated poly(aspartic acid) Increase the Generation and Function of Bone Marrow-derived Dendritic Cells.
abstract: BACKGROUND
  Biodegradable polymers have increasingly been recognized for various biological applications in recent years. Here we examined the immunostimulatory activities of the novel poly(aspartic acid) conjugated with L-lysine (PLA).
  
  
  METHODS
  PLA was synthesized by conjugating L-lysine to aspartic acid polymer. PLA-nanoliposomes (PLA-NLs) were prepared from PLA using a microfluidizer. The immunostimulatory activities of PLA-NLs were examined in mouse bone marrow-derived dendritic cells (BM-DCs).
  
  
  RESULTS
  PLA-NLs increased the number of BM-DCs when added to cultures of GM-CSF-induced DC generation on day 4 after the initiation of cultures. Examination of the phenotypic properties showed that BM-DCs generated in the presence of PLA-NLs are more mature in terms of the expression of MHC class II molecules and major co-stimulatory molecules than BM-DCs generated in the absence of PLA-NLs. In addition, the BM-DCs exhibited enhanced capability to produce cytokines, such as IL-6, IL-12, TNF-α and IL-1β. Allogeneic mixed lymphocyte reactions also confirmed that the BMDCs were more stimulatory on allogeneic T cells. PLA- NL also induced further growth of immature BM-DCs that were harvested on day 8.
  
  
  CONCLUSIONS
  These results show that PLA-NLs induce the generation and functional activities of BM-DCs, and suggest that PLA-NLs could be immunostimulating agents that target DCs.
authors.affiliation: College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea.
authors.forename: Sun-A
authors.initials: SA
authors.lastname: Im
authors.forename: Ki-Hyang
authors.initials: KH
authors.lastname: Kim
authors.forename: Hong-Geun
authors.initials: HG
authors.lastname: Ji
authors.forename: Hyoung-Gyoung
authors.initials: HG
authors.lastname: Yu
authors.forename: Sun-Ki
authors.initials: SK
authors.lastname: Park
authors.forename: Chong-Kil
authors.initials: CK
authors.lastname: Lee