Immune responses of chickens inoculated with recombinantLactobacillusexpressing the haemagglutinin of the avian influenza virus

Abstract

Aims: To develop a safe, effective and convenient vaccine for the prevention of highly pathogenic avian influenza (HPAI), we have successfully constructed a recombinant lactobacillus (LDL17-pH) that expresses the foreign HPAI protein, haemagglutinin 1 (HA 1 ). Methods and Results:The mucosal and systemic immune responses that are triggered by LDL17-pH following the oral administration to 10-day-old chickens were evaluated. The results showed that LDL17-pH could significantly increase the specific anti-HA 1 IgA antibody level in the mucosa and the anti-HA 1 IgG level in sera. Tissues were isolated from trachea and Peyer's patches (PPs)and caecal tonsils of chickens, and gene expression was analysed via realtime quantitative PCR. Conclusions:The results showed that LDL17-pH could significantly induce the specific anti-HA 1 IgA antibody level in the trachea and intestine and the specific anti-HA 1 IgG antibody level in the serum (P < 0Á05). Additionally, LDL17-pH was in the capacity to induce the expression of cytokines IFN-c, TLR-2 and AvBD-9 in the PPs and caecal tonsils. Most importantly, the chickens that were immunized with LDL17-pH were protected against lethal challenge of the H5N1 virus to some extent. Significance and Impact of the Study: Therefore, LDL17-pH could be a promising oral vaccine candidate against HPAI.

Lactobacillus Mucosal Vaccine Vectors: Immune Responses against Bacterial and Viral Antigens

“…These results were seen again in assays using dendritic cell-targeting peptide (DC-pep) adjuvant, which showed improved immune responses and challenge survival in chickens ( 33 ). Similar antibody and T cell results were observed in targeting H5N1 hemagglutinin (HA 1 ) in BALB/c mice ( 34 ) and chickens ( 35 ). Other influenza virus proteins have also been targeted.…”

Effects of in ovo Inoculation of Multi-Strain Lactobacilli on Cytokine Gene Expression and Antibody-Mediated Immune Responses in Chickens

“…Considering the vulnerability of newly hatched chicks toward various pathogens, pre-hatch administration of Lactobacillus bacteria via in ovo technology can be used as a strategy to strengthen immune responsiveness of chickens and reduce their susceptibility toward pathogens. Many studies suggest that different strains of lactobacilli can modulate multiple aspects of immune response including cytokine and chemokine expression, T lymphocyte populations and systemic antibody-mediated responses (21)(22)(23). In the present study, we hypothesized that one-time in ovo administration of a mixture of four Lactobacillus spp.…”

CpG DNA assists the whole inactivated H9N2 influenza virus in crossing the intestinal epithelial barriers via transepithelial uptake of dendritic cell dendrites

“…Gene expression data were collected using 7300 Real-Time PCR System (Applied Biosystems, Hercules, CA) and analyzed by the DDCt methods. 62 The relative CCL20 mRNA was normalized with glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Specific primers were as follows: CCL20 (forward 5 0 -GCCGATGAAGCTTGT GACAT-3 0 and reverse 5 0 -GCTGTGTCCAATTCCATCCC-3 0 ) and GAPDH (forward 5 0 -ATGGTGAAGGTCGGTGTGAA-3 0 and reverse 5 0 -TGGAAGATGGTGATGGGCTT-3 0 ).…”