title: Effects of live attenuated and killed Salmonella vaccine on T-lymphocyte mediated immunity in laying hens.
abstract: The impact of live and killed Salmonella vaccines on cell-mediated immunity (CMI) was investigated in 18- and 32-week-old White Leghorn chickens, by assessing splenic lymphocyte proliferation, expression of IL-2 mRNA in concanavalin A (Con A) stimulated cells and flow cytometric analysis of cell subpopulations. Con A and Salmonella enteritidis (SE) flagella induced proliferation of splenocytes were enhanced in the 18- and 32-week-old chickens treated with live vaccine, compared to the corresponding control chickens. Among the killed vaccine treated birds, Con A-mediated response was higher in the 18-week-old chickens compared to the corresponding control birds. Increased proliferation was accompanied by increased CD4 and reduced CD8 and gammadelta T-lymphocytes in the 18-week-old live vaccine treated chickens. Relative expression of IL-2 mRNA in Con A-stimulated splenocytes from 18-week-old birds was not affected by vaccine treatment. Overall, live vaccine was more effective in increasing the lymphocyte proliferation to Con A as well as SE antigen. This enhanced CMI may prove beneficial in protecting chickens against SE infection.
authors.affiliation: US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 8301, Muirkirk Road HFS 326, Laurel, MD 20708, USA. usb@cfsan.fda.gov
authors.forename: U
authors.initials: U
authors.lastname: Babu
authors.forename: M
authors.initials: M
authors.lastname: Scott
authors.forename: M J
authors.initials: MJ
authors.lastname: Myers
authors.forename: M
authors.initials: M
authors.lastname: Okamura
authors.forename: D
authors.initials: D
authors.lastname: Gaines
authors.forename: H F
authors.initials: HF
authors.lastname: Yancy
authors.forename: H
authors.initials: H
authors.lastname: Lillehoj
authors.forename: R A
authors.initials: RA
authors.lastname: Heckert
authors.forename: R B
authors.initials: RB
authors.lastname: Raybourne
mesh_terms: D000818:Animals; D016516:CD4-CD8 Ratio; D002645:Chickens / Q000276:immunology*; D005260:Female; D007114:Immunization; D008213:Lymphocyte Activation; D011201:Poultry Diseases / Q000517:prevention & control*; D012481:Salmonella Infections, Animal / Q000517:prevention & control*; D022562:Salmonella Vaccines / Q000276:immunology*; D012477:Salmonella enteritidis / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000276:immunology
chemical_list: D022562:Salmonella Vaccines; D014613:Vaccines, Attenuated