Comparison of placenta samples with contamination controls does not provide evidence for a distinct placenta microbiota.

Authors:
Dr. Rita Leite, MD
Dr. Rita Leite, MD
University of Pennsylvania
Program Manager of March of Dimes Prematurity Research Center at University of Pennsylvania
ObGyn Research
Philadelphia, PA | United States

Microbiome 2016 Jun 23;4(1):29. Epub 2016 Jun 23.

Department of Microbiology, Perelman School of Medicine at the University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, PA, 19104-6076, USA.

Background: Recent studies have suggested that bacteria associated with the placenta-a "placental microbiome"-may be important in reproductive health and disease. However, a challenge in working with specimens with low bacterial biomass, such as placental samples, is that some or all of the bacterial DNA may derive from contamination in dust or commercial reagents. To investigate this, we compared placental samples from healthy deliveries to a matched set of contamination controls, as well as to oral and vaginal samples from the same women.

Results: We quantified total 16S rRNA gene copies using quantitative PCR and found that placental samples and negative controls contained low and indistinguishable copy numbers. Oral and vaginal swab samples, in contrast, showed higher copy numbers. We carried out 16S rRNA gene sequencing and community analysis and found no separation between communities from placental samples and contamination controls, though oral and vaginal samples showed characteristic, distinctive composition. Two different DNA purification methods were compared with similar conclusions, though the composition of the contamination background differed. Authentically present microbiota should yield mostly similar results regardless of the purification method used-this was seen for oral samples, but no placental bacterial lineages were (1) shared between extraction methods, (2) present at >1 % of the total, and (3) present at greater abundance in placental samples than contamination controls.

Conclusions: We conclude that for this sample set, using the methods described, we could not distinguish between placental samples and contamination introduced during DNA purification.

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Source
http://dx.doi.org/10.1186/s40168-016-0172-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4917942PMC
June 2016
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References

(Supplied by CrossRef)

R Romero et al.
Science 2014

WB Kidima et al.
Biomed Res Int 2015

K Aagaard et al.
Sci Transl Med 2014

KM Antony et al.
Am J Obstet Gynecol 2015

J Zheng et al.
Nutrients 2015

R Amarasekara et al.
J Obstet Gynaecol Res 2015

MJ Stout et al.
Am J Obstet Gynecol 2013

B Cao et al.
Placenta 2014

SJ Salter et al.
BMC Biol 2014

S Weiss et al.
Genome Biol 2014

ES Charlson et al.
Am J Respir Crit Care Med 2011

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