Biliary Signature of a Bacterial Pathogen
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Biliary Signature of a Bacterial Pathogen For personal use only. Please do not reuse or reproduce without the author’s permission
Transcript of Biliary Signature of a Bacterial Pathogen
Biliary Signature of aBacterial Pathogen
For personal use only.Please do not reuse or reproduce without the author’s permission
Biliary Signature of aBacterial PathogenListeria monocytogenes
The Deadly Deli
The Deadly Deli
Spectrum of Listeriosis• Mild fever and malaise• Mild to severe gastritis
• Severe meningitis in newborns• Bacteremia and sepsis in newborns
• Osteomyelitis and arthritis• Endocarditis
• Asymptomatic carriage• Age-dependent (young and old)
• More frequent in pregnancy• Immune status is critical
L. monocytogenes Intracellular Life CycleTilney and Portnoy
entry
Escape(LLO)
ActA
comet tail
actin cloud
cell-cell spread
LLO+PLCs
Organs Infected by L. monocytogenes
• Intestine• Lymph nodes
• Liver • Spleen
• Brain• CNS
• Bones • Heart
How can one hope to monitor all of these in every animal?
In Vivo Bioluminescence Imaging (BLI)
1000
200
Xenogen Corp.Alameda CA, USA
Photorhabdus luminescens
Day 1
Day 3
Day 2
Day 4
Day 5
2000
200
Survived
1 LD50 (4x104 CFU)
Hardy et al., Science 303:851-3
Localization of Focal Signal to the Gall Bladder Lumen
1. BLI Signal3. Colonies fromlumen on a petri
dish
2. Excised gall bladder4. Bacteria in the
lumen by histology
Hardy et al., Science 303:851-3
Oral Infection
Hardy et al., Science 303:851-3
2000
200
Frequency of Gall Bladder Signals
20 CD1 femalemice given
5x105 CFU of Listeria, imaged
on Day 2
Hardy et al., Infect. Immun. 74(3): 1819-27
Unusual Morphologyof Intralumenal
L. monocytogenes
Pauline Chu, Comparative Medicine
Uninfected
Intralumenal L. monocytogenes
The Gall Bladder
Liver
Gall Bladder
Intestine
Bile duct
The Gall Bladder
Liver
Gall Bladder
Intestine
Bile duct
Questions at this Point
•What is the food source of the bacteria?•Do they adhere to mucus, and if so, how?•What genes are expressed?•Does this process contribute to disease?•What effects are seen on the tissue and contentsof the organ?
•How do the bacteria mitigate the toxicity of the bile salts and other components of bile?
Can they ever GET OUT?
Liver Liver
Gall BladderGall Bladder
3.5 mm4 mm
2.5 mm3 mm
2500
15,000
Jeff Margolis
Hardy et al., Infect. Immun. 74(3): 1819-27
Alan Hofmann
A
B
C
(+)
Daughters of 542.3
147.3
Daughters of 542.3
147.3
m:z 542.3=Monosodium 18:2 Lysophosphatidylcholine
R' = 18-Carbon chain with two double bonds
18:2 Lysophosphatidylcholine
Choline group
Uninfected Animals
Uninfected
Infected
2000
200
Infected
T=0
30 min
60 min
90 min
120 min
20 hours
Human Bile1:3 in H2O
+106 CFU of Listeria
L. monocytogenes Grows in Pure Bile
Bile Culture Dilutions
0.00E+00
5.00E+05
1.00E+06
1.50E+06
2.00E+06
2.50E+06
3.00E+06
3.50E+06
4.00E+06
4.50E+06
T=
0 m
in
T=
5 m
in
T=
10 m
in
T=
15 m
in
T=
20 m
in
T=
25 m
in
T=
30 m
in
T=
35 m
in
T=
40 m
in
T=
45 m
in
T=
50 m
in
T=
55 m
in
T=
60 m
in
T=
65 m
in
T=
70 m
in
T=
75 m
in
T=
80 m
in
T=
85 m
in
T=
90 m
in
time (min)
undiluted
1 to 2
1 to 4
1 to 16
1 to 64
1 to 256
1 to 1024
1 to 4096
Water
Proteins in Mouse Bile
•Pancreatic amylase•Immunoglobulins (antibodies)
•Pancreatic lipases•Sterol esterases
•Carboxypeptidases•Collagen
•α Andrenergic receptor?•Transcription initiation factor TFIID?
The Future• More in vitro cultures with mouse bile, which is
cleaner and has less variation• More mice with the attenuated strain which grows
for a long time without making the mice sick• More protein data from both in vitro and mouse
samples to look for Listeria proteins (!) • Use pure substances and look for changes upon
culture, which will be tricky• Use bacterial mutants such as phospholipase
mutants
People to Thank
Jeff MargolisPauline Chu
Alan HofmannLee Hagey
Janet Bueno
Cormac Gahan
Allis ChienKarolina KrasinskaTheresa McLaughlinLindsay Comeaux
Chris Adams
Christopher H. Contag
