This webinar slidedeck will focus on the acquisition and development of the preterm gut microbiome from birth and following discharge from intensive care. Specifically, the discussion will be around the association of the gut microbiome with necrotizing enterocolitis (NEC) and late onset sepsis (LOS), as well as the impact of birth mode. The other discussion points will be the analysis of multi-omic datasets, including the analysis of the airway microbiome and metabolome in infants hospitalized with bronchiolitis.
3. TMC – 69 entities
21 renowned hospitals
14 support organizations
10 academic institutions
8 academic and research institutions
7 nursing programs
3 public health organizations
3 medical schools
2 pharmacy schools
1 dental school
Texas Medical Centre
18. Key differences in microbiome
acquisition and development
Term infantPreterm infant
Child
?
Reduced:
Diversity
Stability
Bifidobacterium sp.
Lactobacillus sp.
Bacteroides sp.
Increased:
Klebsiella sp.
Staphylococcus sp.
Escherichia sp.
Enterococcus sp.
1-3 Years
of age
Full term Preterm
Stewart and Cummings, Taylor & Francis (In Press)
21. No difference in longitudinal alpha-
and beta- diversity
Stewart, CJ. et al. 2017. FronDers in Microbiology
0
10
20
30
40
0 25 50 75 100
Age in Days
ObservedOTUs
Deliverymode_simple CS V
0.0
0.5
1.0
1.5
2.0
2.5
0 25 50 75 100
Age in Days
ShannonDiversity
Deliverymode_simple CS V
0.0
0.2
0.4
0.6
0.8
0 25 50 75 100
Age in Days
WeightedUniFrac
Deliverymode_simple CS V
0.0
0.2
0.4
0.6
0.8
0 25 50 75 100
Age in Days
UnweightedUniFrac
Deliverymode_simple CS V
A B
C D
Observed OTUS Shannon Diversity
Weighted UniFrac Unweighted UniFrac
Age in days Age in days
0
10
20
30
40
0 25 50 75 100
Age in Days
ObservedOTUs
Deliverymode_simple CS V
0
10
20
30
40
0 25 50 75 100
Age in Days
ObservedOTUs
Deliverymode_simple CS V
Cesarean
Vaginal
22. Vaginal infants ‘kept’ more OTUs
Stewart, CJ. et al. 2017. FronDers in Microbiology
Age in days Age in days
0
5
10
15
0 25 50 75 100
Age in Days
OTUsKept
Deliverymode_simple CS V
0
10
20
0 25 50 75 100
Age in Days
OTUsLost
Deliverymode_simple CS V
0
3
6
9
0 25 50 75 100
Age in Days
OTUsRegained
Deliverymode_simple CS V
0
5
10
15
20
0 25 50 75 100
Age in Days
NewOTUsGained
Deliverymode_simple CS V
C DOTUs Regained New OTUs Gained
A BOTUs Kept OTUs Lost
0
10
20
30
40
0 25 50 75
Age in Days
ObservedOTUs
Deliverymode_simple CS V
0
10
20
30
40
0 25 50 75
Age in Days
ObservedOTUs
Deliverymode_simple CS V
Cesarean
Vaginal
29. Altered microbiome predicts NEC?
Warner, BB. et al. 2016. Lancet
• Increased Gammaproteobacteria in infants diagnosed with NEC acer day 30 of life only
• Most NEC is diagnosed prior to day 30 of life
• Shannon diversity increased in controls but remains consistent in infants later
diagnosed with NEC
• Findings driven by differences in infants under 27 weeks gesta=on
34. PGCT clustering heatmap (PAM)
●
●
●
●
●●
●●
●●
●●
●
●
A
Obs
0
10
20
30
40
50
A B
AlphaDiversity
1 2
A B
C
Status
PGCT
Stewart, CJ. et al. 2016. Microbiome
35. Alpha diversity increased in PGCT 6
●
●
●
●
●●
●●
●●
●●
●
●
●
●
●
●
●
●
●
●
●
●
Adj. P = 1.7e−13
● ●
●●●●
●
Adj. P = 2.9e−61
Observed OTUs Shannon
0
10
20
30
40
50
0
1
2
A B C D E F A B C D E F
AlphaDiversity
PGSTletter
A
B
C
D
E
F
1 2 3 4 5 6 1 2 3 4 5 6
PGCT PGCT
** ****** *** ****** ***
B
Stewart, CJ. et al. 2016. Microbiome
40. Summary
• Longitudinal 16S rRNA gene sequencing studies useful to survey bacterial community
in clinical samples
• Limited to non-invasive stool sampling
• Addi=onal ‘omic technologies (e.g., transcriptomics, proteomics, and metabolomics)
facilitate func=onal analysis
• Correla=ons are important but causality remains elusive
• Discovery research requires further valida=on in animal models and ex vivo cell culture
• Valida=on and mechanis=c understanding of preterm research is especially challenging
due to unique phenotype of immature human gut
• Enteroids1 and organoids2 may pave a new fron=er in preterm research, allowing
ex vivo co-culture of microbiome, primary human cells, and leukocytes
1 – Zachos, NC. et al. 2016. JBC
2 – Hill, DR. et al. 2017. BioRxiv preprint