This document discusses Salmonella, a bacteria that causes foodborne illness in humans. The researchers identified four Salmonella protein antigens - FliK, BcsZ, FhuA, and FepA - as potential vaccine candidates. These proteins were expressed and shown to stimulate immune responses. Mice studies found vaccines for FliK and BcsZ prolonged survival time and decreased mortality compared to controls when exposed to Salmonella. The researchers concluded these protein antigens show potential as cross-protective vaccine candidates against Salmonella infection.

1. By:
Sofía Berrío Martínez
Camila Botero
agosto /4/ 2021
tercer semestre medicina
Universidad Pontificia Bolivariana

2. Salmonella
• Enterobacteriaceae, is a genus of facultative
anaerobic, Gram-negative, oxidase-negative, rod-
shaped bacteria
• two species: Salmonella bongori and Salmonella
enterica, which contained more over 2500 serotypes
• causes several food-borne illnesses in humans,
including non-typhoid diarrhea, gastroenteritis,
bacteremia and enteric fever
Can be transmitted through :
animal-origin food
person-to-person contact
person-to-household pets contact
It has been estimated that annually over 190,000 annual
deaths are caused by Salmonella enterica serovars Typhi and
Paratyphi A, B and C annually (Lozano et al., 2012),
approximately 93 million cases of enteric infections occur and
among them 155,000 patients deaths are caused globally
each year due to diarrhea infected by non-typhoidal
Salmonella

3. Vaccine
• an alternative measure for
preventing bacterial infection while
avoiding the use of antibiotic
• currently licensed Salmonella
vaccines include a live attenuated S.
Typhi strain (Ty21a) (Germanier and
Fiirer, 1975) and the Vi capsular
polysaccharide of S. enterica var.
Typhi against typhoid fever
• sub-unit vaccine candidates of
protein antigens, including SseB
(Reynolds et al., 2014), OmpD (Gil-
Cruz et al., 2009), CirA (Zarate-
Bonilla ´ et al., 2014), PagN et al.
have also been tested, but none of
these have provided efficient
immunogenicity or broad protection
to prevent Salmonella infection.

4. Target
•To select surface-exposed proteins, able to act as
candidates for general vaccine efficacy

5. Materiales y métodos :Western blotting
Permite la identificación de
proteínas especificas
Utiliza anticuerpos marcados
Permite conocer la concentración,
tamaño y composición de la
proteína

6. Materiales y método : ELISA
• abreviación de Enzyme-
Linked ImmunoSorbent
Assay: 'ensayo por
inmunoadsorción ligado a
enzimas
• Usa una enzima como marcador para
mediar la formación de complejo antígeno
anticuerpo

7. Materiales y métodos: PCR
• acción en cadena de la polimerasa
• ensayos moleculares de detección
rápida
• utilizada para amplificar secuencias
de ADN.
• amplifica a partir de cebadores

8. Supervivencia
• DOSIS LETAL 50 %
• LOS RATONES FUERON EVALUADOS POR
30 DIAS PARA EVALUAR LA MORBILIDAD ,
MORTALIDAD Y PORCENTAJE DE
SUPERVIVENCIA

9. Resultados
• 15 proteins were selected randomly for further validation .
• five conserved Salmonella proteins with matched similar
segments of Salmonella among all available species were picked
for further analysis
• four proteins including FliK, BcsZ, FhuA, and FepA were
successfully expressed for further in vivo experimental validation
• To identify whether target genes of the four candidate vaccines
were detectable in the 28 strains of Salmonella the fepA, fliK,
bcsZ genes were detectable in all of the 28 tested strains of
Salmonella, and fhuA was present in 27 of the 28 strains, which
provided for the four
• four predicted vaccine proteins stimulated both the T helper cell
type 1 (Th1) and T helper cell type 2 (Th2 )
• in the antiserum against BcsZ could reach 0.69. The increase in
IgM antibody levels indicated an initial antibody synthesis in the
humoral immunity reactionn
• the T helper cell type 1 (Th1) and T helper cell type 2 (Th2 )
• in the antiserum against BcsZ could reach 0.69. The increase in
IgM antibody levels indicated an initial antibody synthesis in the

10. Resultados
• The increase For the FliK-a protein, could stably exert a
cross-reaction to 26 of the 28 strains, with an antigenic
coverage of 92.86 % among tested Salmonella strains
• results indicated that the immunity of FliK and BcsZ could
influence the colonization of Salmonella in organs and
alleviate the organs damage caused by Salmonella
infection to prolong survival time of mice and significantly
decreased mortality compared with control mice.

11. Results

12. Results

13. Discussion
Author Hypothesis yes/no
Maria et al., 2017 "There is a greater probability for
those vaccines targeting these
antigens to generate protective
responses"
yes
Ahmad et al., 2016 "BcsZ is required for efficient
pathogen-host interaction … when S.
Typhimurium invades ephitelial
cells..."
yes
Josenhans and Suerbaum, 2002 "...The flagellum FliK... may potentially
confer partial protection against
Salmonella..."
yes

14. Conclusions
Understand pathologies Knowledge about the genome
and reverse vaccinology
Western blood and PCR helps
us find new solutions for
salmonella

15. Mapa conceptual 1

16. Mapa conceptual 2