Understanding how Campylobacter colonizes chickens and ... · former Campy team members: David...

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VictorDiRita

DepartmentofMicrobiology&MolecularGene8csMichiganStateUniversity

UnderstandinghowCampylobactercolonizeschickensandadulteratesthefoodsupply

former Campy team members: David Hendrixson, Ph.D. Lindsay Davis Gielda, Ph.D. Michael Taveirne, Ph.D Tsutomu Kakuda, D.V.M., Ph.D. Jeremiah Johnson, Ph.D. key collaborators Kate Eaton, D.V.M. – Michigan Vincent Young, M.D., Ph.D. – Michigan Jonathan Livny, Ph.D. – Broad Institute Jennifer Gaddy, Ph.D. – Vanderbilt University Bruce Cooper, Ph.D. – Purdue University William Miller, Ph.D. & team - USDA, Albany, CA

acknowledgments

DiRita Lab Natalia Martin, Ph.D. Jessica Beauchamp, Ph.D. Rhiannon Levecque, M.S. Chanrith Siv Andrew Van Alst Husnain Ahmed Cole McCutcheon Olivia Walser Joe Hostnik Ben Sims Melissa Meschkewitz Alex DeRita

Rudolph M. Hugh Endowment

Measuring progress toward Healthy People 2020 goals2015 FOOD SAFETY REPORT

Pathogen Healthy People 2020 Target Rate* 2015 Rate† Change Compared with 2006-2008§

Campylobacter 8.5 12.97 © 9%

E. coli O157¶ 0.6 0.95 ª 30%

Listeria 0.2 0.24 No change

Salmonella 11.4 15.89 No change

Vibrio 0.2 0.39 © 34%

Yersinia 0.3 0.29 No change

*Per 100,000 population†Culture-confirmed infections per 100,000 population

§2006-2008 were the baseline years used to establish Healthy People 2020 targets¶Shiga toxin-producing Eschericha coli O157

For more information, visit www.cdc.gov/foodnetCS264717-A April 2016

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today

1. farm & laboratory models of association between Campylobacter/chicken/microbiota 2.  what traits are used by C. jejuni to colonize chickens? •  zinc wars in the gut

3.  can we reduce the colonization of C. jejuni in chickens? •  campynexin campaign

naturally-infectedchickens

Campyloadsinfarm-raisedadultchickens

C.jejunimono-colonized

C.jejuni+C.colico-colonized

farmbirdmicrobiomeprofile

Family

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 200

20

40

60

80

100

Rel

ativ

e A

bund

ance

Campylobacter

nocorrela8onbetweencecalmicrobiotastructureandCampylobactercoloniza8onload

experimentalchickcoloniza8on

LabAnimals FarmAnimals

Day-of-HatchModel1x103CFUC.jejuni

Coloniza8onfor7-days

taleoftwoceca–labv.farmbirds

7differentfamilymembers

labbirdsFamily

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 200

20

40

60

80

100

Rel

ativ

e A

bund

ance

76differentfamilymembers

farmbirdsCampylobacteraceae

what traits are used by C. jejuni to colonize chickens? •  zinc wars in the gut

STM-derived mutants without motility defects zinc ABC transporter - ZnuABC

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STM-derived mutants without motility defects

chick colonization phenotypes of wild type and znuA mutant C. jejuni

znuA

cfu/gm

cecalcon

tent

w.t. znuA/pznuA

znuA

early colonization dynamics of wild type and znuA mutant

23456789

10

Hours Post Inoculation

cfu

g-1 c

ecal

con

tent

s

6 12 24 48

p = 0.052 p = 0.0024181-176 StR

ΔznuA

coincides with earliest time of cultivable microbes

colonization of germ free mice and limited-microbiota chicks by znuA mutant

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10

81-176 StR

ΔznuA

n=4 n=4 n=8 n=8 n=8 n=8 n=8 n=8

p < 0.0001

Germ-Free Mice Limited-Flora Chicks Limited-Flora Chicks Conventional ChicksInoculum 106 cfu Inoculum 106 cfu Inoculum 104 cfu Inoculum 104 cfu

cfu

g-1 c

ecal

con

tent

s

germfreemice limitedmicrobiotachicksconven8onalchicks

fecal transplant

limitedmicrobiotachick+ΔznuA

feedfecalpelletsfromconven8onalsevendaybird

cecalCampycountsat3,7,10dayspostfeeding

coven8onalchick+ΔznuA.

reduced colonization loads of znuA after fecal transplant

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10

3 7 10

Days Post Inoculation

p = 0.0011 p < 0.0001

ΔznuAΔznuA, conventionalized

n=4 n=8 n=8 n=7 n=7

cfu

g-1 c

ecal

con

tent

s

23456789

10

3 7 10

Days Post Inoculation

81-176 StR

81-176 StR, conventionalized

n=4 n=8 n=8 n=8 n=8

cfu

g-1 c

ecal

con

tent

s

can we reduce the colonization of C. jejuni in chickens? •  campynexin campaign

campynexin campaign

campynexins

campynexinB

compoundAcampynexinA

C.jejuni

C.jejuni

EC50: 8.18 uM EC50: 11.9 uM

EC50: 10.4 uM EC50: 37.4 uM

EC50: 8.96 uM

campynexindose-responsecurves

selec8vityofcampynexins

campynexin A effects

•  dosed at time of inoculation, day 3 & day 6 post-inoculation

•  no obvious pathology –  no evident inflammation –  healthy tissue

WT+DMSO WT+campynexinA

treatment

avg.weight(perbird)

WT+DMSO 46.8g

WT+campynexinA 50.3g

PBS+DMSO 48.1g

campynexin A v. Campy in chick model

commonly acquired from food sources

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Thank you!

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