Self-destructing Salmonella via temperature induced gene E of phage PhiX174 improves influenza HA DNA vaccine immune protection against H1N1 infection in mice model.

The delivery of DNA vaccines is the principle impediment for implementation of DNA vaccination on a mass scale. In this study, we report a temperature induced conditionally expressed phage PhiX174 gene E mediated lysis of Salmonella under in vivo conditions that can increase the immunogenicity of a DNA vaccine delivered via Salmonella carrier system. We electroporated gene E encoding lysis plasmid pJHL187 along with the pcDNA-HA plasmid encoding H1N1 HA into attenuated Salmonella Typhimurium, strain JOL1893.

Intracellular delivery of HA1 subunit antigen through attenuated Salmonella Gallinarum act as a bivalent vaccine against fowl typhoid and low pathogenic H5N3 virus.

Introduction of novel inactivated oil-emulsion vaccines against different strains of prevailing and emerging low pathogenic avian influenza (LPAI) viruses is not an economically viable option for poultry. Engineering attenuated Salmonella Gallinarum (S. Gallinarum) vaccine delivering H5 LPAI antigens can be employed as a bivalent vaccine against fowl typhoid and LPAI viruses, while still offering economic viability and sero-surveillance capacity.

Live-attenuated auxotrophic mutant of Salmonella Typhimurium expressing immunogenic HA1 protein enhances immunity and protective efficacy against H1N1 influenza virus infection.

Aim: To evaluate the efficacy of attenuated Salmonella Typhimurium (JOL912) as a live bacterial vaccine vector.

Materials & Methods: The JOL912 engineered to deliver HA1 protein from influenza A/Puerto Rico/8/1934 (H1N1; PR8) virus was coined as JOL1635 and further evaluated for immunogenicity and protective efficacy.

Results: The JOL1635 stably harbored the HA1 gene within pMMP65 plasmid with periplasmic expression and effective delivery of HA1 protein to RAW264.

Orally administered live attenuated Salmonella Typhimurium protects mice against lethal infection with H1N1 influenza virus.

Pre-stimulation of toll-like receptors (TLRs) by agonists has been shown to increase protection against influenza virus infection. In this study, we evaluated the protective response generated against influenza A/Puerto Rico/8/1934 (PR8; H1N1) virus by oral and nasal administration of live attenuated Salmonella enterica serovar Typhimurium, JOL911 strain, in mice. Oral and nasal inoculation of JOL911 significantly increased the mRNA copy number of TLR-2, TLR4 and TLR5, and downstream type I interferon (IFN) molecules, IFN-α and IFN-β, both in peripheral blood mononuclear cells (PBMCs) and in lung tissue.

A live attenuated Salmonella Enteritidis secreting detoxified heat labile toxin enhances mucosal immunity and confers protection against wild-type challenge in chickens.

A live attenuated Salmonella Enteritidis (SE) capable of constitutively secreting detoxified double mutant Escherichia coli heat labile toxin (dmLT) was developed. The biologically adjuvanted strain was generated via transformation of a highly immunogenic SE JOL1087 with a plasmid encoding dmLT gene cassette; the resultant strain was designated JOL1641. A balanced-lethal host-vector system stably maintained the plasmid via auxotrophic host complementation with a plasmid encoded aspartate semialdehyde dehydrogenase (asd) gene.

Interaction of a live attenuated Salmonella Gallinarum vaccine candidate with chicken bone marrow-derived dendritic cells.

Salmonella enterica serovar Gallinarum (SG) is a Gram-negative intracellular host-adapted pathogen that causes fowl typhoid. Attenuated strains of SG are proven and widely used vaccine candidates because of advantages like induction of strong humoral and cell-mediated immune responses. In the present study, we investigated the interaction of chicken bone marrow-derived dendritic cells (chBM-DCs) with an attenuated SG (JOL1355) strain that secretes a heat-labile enterotoxin B subunit protein previously shown to successfully vaccinate chickens.

Protective effects of recombinant glycoprotein D based prime boost approach against duck enteritis virus in mice model.

Duck virus enteritis, also known as duck plague, is an acute herpes viral infection of ducks caused by duck enteritis virus (DEV). The method of repeated immunization with a live attenuated vaccine has been used for the prevention and control of duck enteritis virus (DEV). However, the incidence of the disease in vaccinated flocks and latency reactivation are the major constraints in the present vaccination programme.

Evolutionary and bioinformatic analysis of the spike glycoprotein gene of H120 vaccine strain protectotype of infectious bronchitis virus from India.

The infectious bronchitis virus is a causative agent of avian infectious bronchitis (AIB), and is is an important disease that produces severe economic losses to the poultry industry worldwide. Recent AIB outbreaks in India have been associated with poor growth in broilers, drop in egg production, and thin egg shells in layers. The complete spike gene of Indian AIB vaccine strain was amplified and sequenced using a conventional reverse transcription polymerase chain reaction and is submitted to the GenBank (accession no KF188436).