PMID- 23870437
OWN - NLM
STAT- MEDLINE
DCOM- 20140122
LR  - 20211021
IS  - 1743-422X (Electronic)
IS  - 1743-422X (Linking)
VI  - 10
DP  - 2013 Jul 20
TI  - Engineering lentiviral vectors for modulation of dendritic cell apoptotic 
      pathways.
PG  - 240
LID - 10.1186/1743-422X-10-240 [doi]
AB  - BACKGROUND: Dendritic cells (DCs) are promising mediators of anti-tumor immune 
      responses due to their potent antigen-presentation capacity. Unfortunately, 
      cancer cells can often disarm differentiated DCs by rendering them incapable of 
      maturation or by promoting their apoptosis. DC vaccine regimens attempt to 
      generate functional DCs and preload them with Tumor-Associated Antigens (TAAs) to 
      target various malignancies. Despite these efforts, the efficacy of DC vaccines 
      in clinical trials is still rather disappointing to date. In addition to 
      undergoing cancer-induced apoptosis, it is well established that DCs are 
      intrinsically short-lived cell types. It is likely that a significant portion of 
      infused DCs undergo apoptosis prior to locating and activating naive TAA-reactive 
      T cells. METHODS: In our current study, we constructed and investigated novel 
      bicistronic lentivectors (LVs) encoding the cDNA for the xeno-TAA, rat HER-2/neu 
      (rHER-2), along with five candidate mouse DC survival factors (c-FLIPS, c-FLIPL, 
      Bcl-XL, M11L, and AKT-1) that operate in both the extrinsic and intrinsic cycles 
      of apoptosis. The murine DC cell line, DC2.4 was transduced separately with each 
      novel LV construct. Infected cells were enriched via flow cytometric methods 
      based on rHER-2 expression. Transduced DC2.4 cell lines were then exposed to 
      Fetal Calf Serum (FCS) withdrawal and to specific pharmacological 
      apoptosis-inducing agents. DC2.4 cell death was assayed based on Annexin V and PI 
      double-positive staining via flow cytometry. The phenotype and function of 
      transduced DC2.4 cells and primary bone marrow-derived DCs were then assessed via 
      expression and secretion of DC markers and cytokines, respectively. RESULTS: 
      DC2.4 cells transduced with LVs encoding cDNAs for c-FLIPS, c-FLIPL, Bcl-XL, and 
      M11L were protected from apoptosis when exposed to low FCS-containing culture 
      media. When treated with an anti-CD95 antibody, only DC2.4 cells transduced with 
      LVs encoding c-FLIPS and c-FLIPL were protected from apoptosis. In contrast, only 
      DC2.4 cells transduced with LVs encoding Bcl-XL and M11L were protected from 
      effects of staurosporine (STS) treatment. Also, LV-modified DCs maintained their 
      original phenotype and function. CONCLUSIONS: We present evidence that by 
      employing novel recombinant bicistronic LVs we can simultaneously load DCs with a 
      relevant TAA and block apoptosis; thereby confirming the usage of such LVs in the 
      modulation of DC lifespan and function.
FAU - Wang, James C M
AU  - Wang JC
AD  - University Health Network, Canadian Blood Services Building, 67 College St, Room 
      406, Toronto, Ontario M5G2M1, Canada.
FAU - Felizardo, Tania C
AU  - Felizardo TC
FAU - Au, Bryan C Y
AU  - Au BC
FAU - Fowler, Daniel H
AU  - Fowler DH
FAU - Dekaban, Gregory A
AU  - Dekaban GA
FAU - Medin, Jeffrey A
AU  - Medin JA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20130720
PL  - England
TA  - Virol J
JT  - Virology journal
JID - 101231645
RN  - 0 (Antigens, Neoplasm)
SB  - IM
MH  - Animals
MH  - Antigens, Neoplasm/genetics/*immunology
MH  - *Apoptosis
MH  - Cell Survival
MH  - Dendritic Cells/*immunology/*physiology/virology
MH  - Flow Cytometry
MH  - Genetic Engineering/*methods
MH  - *Genetic Vectors
MH  - Lentivirus/*genetics
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Transduction, Genetic
PMC - PMC3723442
EDAT- 2013/07/23 06:00
MHDA- 2014/01/23 06:00
PMCR- 2013/07/20
CRDT- 2013/07/23 06:00
PHST- 2013/04/21 00:00 [received]
PHST- 2013/07/17 00:00 [accepted]
PHST- 2013/07/23 06:00 [entrez]
PHST- 2013/07/23 06:00 [pubmed]
PHST- 2014/01/23 06:00 [medline]
PHST- 2013/07/20 00:00 [pmc-release]
AID - 1743-422X-10-240 [pii]
AID - 10.1186/1743-422X-10-240 [doi]
PST - epublish
SO  - Virol J. 2013 Jul 20;10:240. doi: 10.1186/1743-422X-10-240.