To develop a cell-penetrating chimeric apoptotic peptide AVPI-LMWP/DNA co-delivery system for cancer therapy, we prepared the AVPI-LMWP/pTRAIL self-assembled complexes containing a therapeutic combination of peptide drug AVPI and DNA drug TRAIL. The chimeric apoptotic peptide AVPI-LMWP was synthesized using the standard solid-phase synthesis. The cationic AVPI-LMWP could condense pTRAIL by electrostatic interaction. The physical-chemical properties of the AVPI-LMWP/pTRAIL complexes were characterized. The cellular uptake efficiency and the inhibitory activity of the AVPI-LMWP/pTRAIL complexes on tumor cell were also performed. The results showed that the AVPI-LMWP/pTRAIL complexes were successfully prepared by co-incubation. With the increase of mass ratio (AVPI-LMWP/DNA), the particle size was decreased and the zeta potential had few change. Agarose gel electrophoresis showed that AVPI-LMWP could fully bind and condense pTRAIL at a mass ratio above 15:1. Cellular uptake efficiency was improved along with the increased ratio of W(AVPI-LMWP)/WpTRAIL. The in vitro cytotoxicity experiments demonstrated that the AVPI-LMWP/pTRAIL (W:W = 20:1) complexes was significantly more effective than the pTRAIL, AVPI-LMWP alone or LMWP/pTRAIL complexes on inhibition of HeLa cell growth. Our studies indicated that the AVPI-LMWP/pTRAIL co-delivery system could deliver plasmid into HeLa cell and induce tumor cell apoptosis efficiently, which showed its potential in cancer therapy using combination of apoptoic peptide and gene drugs.
Antineoplastic Agents ; chemistry ; Cell-Penetrating Peptides ; chemistry ; DNA ; chemistry ; Drug Delivery Systems ; HeLa Cells ; Humans ; Neoplasms ; drug therapy ; Particle Size ; Plasmids

OBJECTIVETo establish a stable method for obtaining large quantity of highly purified immature dendritic cells (imDCs) in vitro, and identify the morphology, function and surface markers of the cells.

METHODSCD117(+) hemopoietic stem cells (HSCs) were isolated and purified from the bone marrow of healthy C57 mice by magnetic affinity cell sorting. After cell expansion by treatment with stem cell factor (SCF) and interleukin-3 (IL-3), the HSCs were induced for directional differentiation into imDCs by treatment with GM-CSF, IL-4 and IL-10. The imDCs obtained were identified by morphological and functional observation under inverted microscope, scanning electron microscope and transmission electron microscope, followed by detection of the expressions of the surface markers using flow cytometry.

RESULTSAfter 3, 5 and 7 days of culture in the presence of SCF+IL-3, the cells were expanded by 10.34-/+1.43, 22.65-/+2.71 and 54.39-/+3.08 folds, respectively. The HSCs were successfully induced to differentiate into imDCs with phagocytotic activity. The dendrites of the imDCs were short small, and appearing spinous. The expressions of surface markers were detected from the cells showing the phenotype of CD11c(+), I-A/I-E(low), CD40(-), CD80(-), CD86(-).

CONCLUSIONThe method described allows steadily acquisition of large quanty of highly purified imDCs and of their effective identification in vitro.

Animals ; Cell Culture Techniques ; methods ; Cell Differentiation ; Cell Separation ; methods ; Cells, Cultured ; Dendritic Cells ; cytology ; Flow Cytometry ; Hematopoietic Stem Cells ; cytology ; Mice ; Mice, Inbred C57BL ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Proto-Oncogene Proteins c-kit

Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)-induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.
Active Transport, Cell Nucleus ; Animals ; Coronavirus Infections ; immunology ; veterinary ; virology ; Genes, Viral ; Host-Pathogen Interactions ; immunology ; Interferons ; antagonists & inhibitors ; biosynthesis ; genetics ; Interleukins ; antagonists & inhibitors ; biosynthesis ; genetics ; NF-kappa B ; metabolism ; Nucleocapsid Proteins ; genetics ; immunology ; physiology ; Porcine epidemic diarrhea virus ; genetics ; pathogenicity ; physiology ; Promoter Regions, Genetic ; Swine ; Swine Diseases ; immunology ; virology