Immunogenicity of a Salmonella Enteritidis mutant as vaccine candidate and its protective efficacy against salmonellosis in chickens

Characterization of a Novel Inactivated Salmonella enterica Serovar Enteritidis Vaccine Candidate Generated Using a Modified cI857/λ PR/GeneEExpression System

“…Bacterial growth is a prerequisite for gene E lysis, because the tunnel structure is formed only in the growing regions of the cell, such as the central division zone or the pole zone (22). Strains carrying a conventional ghost cassette system are generally able to survive at 28°C (15,41), whereas the ghost strain used in the present study was grown at 37°C, which is the optimum temperature for normal growth of Salmonella (24,31). As suboptimal growth temperatures reduce the rate of bacterial multiplication, they slow the production process of BGs.…”

“…A gross lesion score of 0, 1, 2, or 3 was given based on the number of necrotic foci on the organ and the extent of organ enlargement. A score of 0 indicated no lesion, a score of 1 was assigned to necrotic foci, a score of 2 indicated enlarged and necrotic organs, and a score of 3 was associated with more debilitated, necrotic, and distorted organs (31). Aseptically collected tissue samples were homogenized and preenriched in 3 ml buffered peptone water (BPW) (Becton Dickinson and Company), and 100 l of homogenates was plated on brilliant green agar (BGA) (Becton Dickinson and Company) for determination of the bacterial count on direct culture.…”

“…An S. Enteritidis-positive bird was defined based on recovery of S. Enteritidis from any of the internal organs (liver, spleen, and cecum) studied in an assay. The percent efficacy of protection for a particular group was calculated based on the number of S. Enteritidis-positive birds out of the total number of birds in a group (31).…”

Salmonella enterica Serovar Enteritidis Ghosts Carrying the Escherichia coli Heat-Labile Enterotoxin B Subunit Are Capable of Inducing Enhanced Protective Immune Responses

“…To quantify S. Enteritidis-specific plasma IgG and intestinal sIgA titers, outer membrane protein (OMP) (extracted from S. Enteritidis strain JOL860 cells) was used as the coating antigen. The titers of anti-OMP plasma IgG and intestinal sIgA antibodies were determined by using a chicken IgG and IgA ELISA quantitation kit (Bethyl Laboratories, Montgomery, TX, USA), as previously described (21). To determine LTB-specific plasma IgG titers, purified LTB was used as the coating antigen.…”

Evaluation of immunogenicity and protective efficacy of adjuvantedSalmonellaTyphimurium ghost vaccine against salmonellosis in chickens

“…The OMP mixture was extracted from JOL401, as described previously (Kang et al 2002). The indirect enzyme linked immunosorbent assay (ELISA) was carried out for detection of S. Typhimurium OMP-specific IgG and sIgA using a chicken IgG and IgA ELISA quantitation kit (Bethyl Laboratories, Montgomery, TX, USA), as previously described (Nandre et al 2011). The wells of a Microlon Ò ELISA plate were coated with 100 mL OMP at a concentration of 0.2 mg/mL.…”