title: Cytotoxicity and immunological responses following oral vaccination of nanoencapsulated avian influenza virus H5 DNA vaccine with green synthesis silver nanoparticles.
abstract: DNA formulations provide the basis for safe and cost effective vaccine. Low efficiency is often observed in the delivery of DNA vaccines. In order to assess a new strategy for oral DNA vaccine formulation and delivery, plasmid encoding hemagglutinin (HA) gene of avian influenza virus, A/Ck/Malaysia/5858/04 (H5N1) (pcDNA3.1/H5) was formulated using green synthesis of sliver nanoparticles (AgNP) with polyethylene glycol (PEG). AgNP were successfully synthesized uniformly dispersed with size in the range of 4 to 18 nm with an average size of 11 nm. Cytotoxicity of the prepared AgNP was investigated in vitro and in vivo using MCF-7 cells and cytokine expression, respectively. At the concentration of -5 log₁₀AgNP, no cytotoxic effects were detected in MCF-7 cells with 9.5% cell death compared to the control. One-day-old specific pathogen-free (SPF) chicks immunized once by oral gavage with 10 μl of pcDNA3.1/H5 (200 ng/ml) nanoencapsulated with 40 μl AgNP (3.7×10⁻² μg of Ag) showed no clinical manifestations. PCR successfully detect the AgNP/H5 plasmid from the duodenum of the inoculated chicken as early as 1h post-immunization. Immunization of chickens with AgNP/H5 enhanced both pro inflammatory and Th1-like expressions, although no significant differences were recorded in the chickens inoculated with AgNP, AgNP/pcDNA3.1 and the control. In addition, serum samples collected from immunized chickens with AgNP/H5 showed rapidly increasing antibody against H5 on day 14 after immunization. The highest average antibody titres were detected on day 35 post-immunization at 51.2±7.5. AgNP/H5 also elicited both CD4+ and CD8+ T cells in the immunized chickens as early as day 14 after immunization, at 7.5±2.0 and 20±1.9 percentage, respectively. Hence, single oral administrations of AgNP/H5 led to induce both the antibody and cell-mediated immune responses as well as enhanced cytokine production.
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Seyed Davoud
authors.initials: SD
authors.lastname: Jazayeri
authors.forename: Aini
authors.initials: A
authors.lastname: Ideris
authors.forename: Zunita
authors.initials: Z
authors.lastname: Zakaria
authors.forename: Kamyar
authors.initials: K
authors.lastname: Shameli
authors.forename: Hassan
authors.initials: H
authors.lastname: Moeini
authors.forename: Abdul Rahman
authors.initials: AR
authors.lastname: Omar
mesh_terms: D000818:Animals; D000917:Antibody Formation; D045744:Cell Line, Tumor; D002470:Cell Survival; D002645:Chickens; D016207:Cytokines / Q000276:immunology; D005786:Gene Expression Regulation; D055772:Green Chemistry Technology; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics* / Q000276:immunology; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics* / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D005585:Influenza in Birds / Q000235:genetics / Q000276:immunology / Q000517:prevention & control*; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology
chemical_list: D016207:Cytokines; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D019444:Vaccines, DNA; D012834:Silver