THE VAGINAL MICROBIOTA IN HEALTH AND DISEASE
JACQUES RAVEL INSTITUTE FOR GENOME SCIENCES UNIVERSITY OF MARYLAND SCHOOL OF MEDICINE
Let’s Talk MPT
CAMI Health/Initiative for MPTs/Public Health Institute
December 10, 2020 DISCLOSURES
I am the co-founder of LUCA Biologics, a biotechnology company focusing on translating microbiome research into live biotherapeutics drugs for women's health.
CST I CST V CST III VAGINAL MICROBIOTA
• In reproductive age women, Lactobacillus spp. are often characteristic of an optimal vaginal microbiota
• Lactobacillus spp. are lactic acid producers and acidify the vagina to pH < 4
• An acidic environment is thought to restrict the growth of non-indigenous microbes
• Changing environment throughout a women’s lifespan - microbiota changes accordingly CST I CST V CST III THE VAGINAL MICROBIOTA THROUGH THE LIFESPAN
Pre- Birth Menarche Reproductive Years Menopause menarche
CST I CST VLactobacillus CST III Estrogen ESTROGEN AND EPITHELIAL CELL MATURATION
Estrogen Lactobacillus Glycogen Sugars Estrogen THE VAGINAL MICROBIOTA THROUGH THE LIFESPAN
Pre- Birth Menarche Reproductive Years Menopause menarche
Lactobacillus
Estrogen VAGINAL MICROBIOTA COMPOSITION AND STRUCTURE
020406080 100 % taxon abundance Well-powered study of 400 asymptomatic women, equally representing 4 ethnic groups
CST II III I V IV Five major community state types that difer in their L. iners L. crispatus L. gasseri microbial composition and abundance L. jensenii Prevotella Megasphaera Community state type IV lacks signifcant number of Sneathia Atopobium Lactobacillus - higher diversity - (non optimal) Streptococcus Dialister Lachnospira Anaerococcus CST V Peptoniphilus Eggerthella Finegoldia Rhodobaca Anaerotruncus Ureaplasma Mycoplasma CST IV Aerococcus CST II Parvimonas Staphylococcus Corynebacterium Veillonella L.vaginalis Community groups
CST I CST III Shannon Diversity Index 01234
Ravel et al. The vaginal microbiome of reproductive age women. PNAS. 2011. 108 Suppl 1, 4680–4687. COMMUNITY STATE TYPES
• Community State Types (CST) aford reducing the high dimensionality of microbiota compositional data
• CSTs represents sets of microbes, which together can be associated with a specifc outcomes
• CSTs carry biological information that can be interpreted
• CST-level analysis complements phylotype-level analysis which can be difcult to interpret as the context of the microbiota composition is not considered
• However, current CST classifcation is difcult to compare study to study, is highly sensitive to adding or removing samples, and CST are broadly defned
• Develop a tool to reproducibly classify vaginal microbiota into better defned CSTs VAGINAL MICROBIOTA COMPOSITION AND STRUCTURE
Community state type classifcation based on over 13,000 samples (16S rRNA gene V3-V4 regions)
Expanded high resolution classifcation and CST hierarchy
I II III IV V
I-A I-B II III-A III-B IV-A IV-B IV-C V
I-A I-B II III-A III-B IV-A IV-B IV-C0 IV-C1 IV-C2 IV-C3 IV-C4 V
Streptococcus Bifdobacterium Enterococcus Staphylococcus
VALENCIA: VAginaL community state typE Nearest CentroId clAssifer github.com/ravel-lab/VALENCIA
France M et al. Microbiome. 2020 FREQUENCY OF COMMUNITY TYPES IN ETHNIC GROUPS
Asian Caucasian
Hispanic Black IMPROVED RESOLUTION IN CST ASSIGNMENTS
Asian Caucasian
Hispanic Black THE DYNAMICS OF THE VAGINAL MICROBIOTA
100 100 160 women L crispatus L iners e (%) e (%) L iners 80
c Streptococcus c 80 L otu4 Corynebacterium L gasseri Finegoldia 60 60 L vaginalis L crispatus Daily sampling e abundan Clostridium e abundan v v ti
ti Staphylococcus
a L crispatus 1 40 a 40 el el r Peptoniphilus L jensenii r Streptococcus Anaerococcus ype ype t 20 Gemella t 20 L gasseri ylo ylo h
h 10-week study
P L jensenii P 0 0 10 7 10 Nugent Score 7 3 Nugent Score 0 3 7 0 6 pH 7 5 6 pH 4 5 4
0 1 2345 6789 10 weekseeks 0 1 2345 6789 10 weeks
100 100 Atopobium vaginae Gardnerella vaginalis Gardnerella vaginalis BVAB2 e (%) 80 Others 80 c e (%) BVAB3 c Bifidobacteriaceae Megasphaera sp type 1 Atopobium vaginae Others BVAB2 60 60 Mobiluncus Lactobacillus iners e abundan
candidate division TM7 v e abundan
ti Aerococcus christensenii v a ti Parvimonas micra Megasphaera sp type 1 el a Peptoniphilus r 40 el 40 Lactobacillus crispatus r Bifidobacteriaceae
ype Bifidobacterium bifidum t
ype Anaerococcus tetradius t Lactobacillus jensenii Prevotella genogroup 1 ylo h ylo 20 20 P
h Bacteria P Finegoldia magna Anaerococcus 0 0 10 10 7 7 Nugent Score Nugent Score 3 3 0 0 7 7 6 6 pH pH 5 5 4
012 345 6789 10 012 345 6789 10 weeks weeks
100 Gardnerella vaginalis 100 Gardnerella vaginalis Others Lactobacillus iners Lactobacillus crispatus Megasphaera sp type 2 Others Atopobium vaginae 80 Lactobacillus iners 80 Atopobium vaginae e (%) e (%) c c Bifidobacteriaceae Prevotella genogroup 1 BVAB2 Streptococcus agalactiae Megasphaera sp type 2 Anaerococcus 60 Veillonella montpellierensis 60 BVAB1 Peptoniphilus BVAB2 e abundan e abundan
BVAB3 v Peptoniphilus v ti
ti Parvimonas micra Finegoldia magna a a
Peptostreptococcus el 40 BVAB3 r el 40 r Streptococcus Prevotella Aerococcus christensenii Clostridiales ype ype Finegoldia magna t
t Prevotella genogroup 2 Peptoniphilus lacrimalis ylo Anaerococcus tetradius
ylo 20 20 Lactobacillus gasseri h
h Aerococcus christensenii P P Megasphaera sp type 1 Bacteria Lactobacillus jensenii Peptostreptococcus Streptococcus anginosus 0 Bacillales 0 Bacillales candidate division TM7 Streptococcus salivarius Streptococcus anginosus BVAB1 Enterococcus faecalis 0 1 2345 6789 10 Streptococcus agalactiae 0 1 2345 6789 10 Prevotella bivia Mobiluncus curtisii weeks weeks Actinobacteria class 10 10 7 Nugent Score 7 Nugent Score 3 3 0 0 7 7 6 pH 6 pH 5 5 4 4 THE DYNAMICS OF THE VAGINAL MICROBIOTA
Stability (rate of change) of the microbiota on time in the menstrual cycle analysis
Estrogen
Progesterone
The rate of community change is afected by time in the menstrual cycle (natural change) NON OPTIMAL VAGINAL MICROBIOTA NON OPTIMAL VAGINAL MICROBIOTA
• The ‘‘clinical iceberg’’ concept of adverse health outcomes, applied to BV. With better molecular methods, we now appreciate that clinically evident BV, as diagnosed by a technique such as Amsel’s criteria (Amsel-BV), does not capture a high proportion of women diagnosed with BV by Nugent (Nugent-BV) or with molecular methods (Molecular- BV) that contributes to adverse sexual and reproductive health outcomes, including increased HIV risk.
• There is a need to standardize our evaluation of non optimal vaginal microbiota in clinical studies HOW TO STUDY THE MICROBIOME
Diferent questions – DiferentC approaches
Who is there? (microbiota) Metataxonomic – relies on the sequencing of a marker genes ubiquitous to all bacteria and archea,C or all eukaryotes. Survey of the composition and abundance of these microbes. The most robust gene is the 16S rRNA gene and 18S rRNA gene for eukaryotes.
CST I CST V CST III THE 16S RIBOSOMAL RNA GENE
The ribosome comprises protein and structural RNAs. The 16S rRNA is part of the small subunit of the ribosome of bacteria and archaea.
It has conservedC and variable C regions. The conserved regions are useful for designing PCR primers and the variable regions useful for taxonomy and phylogeny. CST I CST V CST III It is like a bacterial ID. HOW TO STUDY THE MICROBIOME
Who is there? (microbiota) Metataxonomic – relies on the sequencing of a marker genes ubiquitous to all bacteria and archea,C or all eukaryotes. Survey of the composition and abundance of these microbes. The most robust gene is the 16S rRNA gene and 18S rRNA gene for eukaryotes.
Comparison to CST I CST V sequenceCST III databases Bioinformatics METATAXONOMICS - COMPOSITIONAL/STRUCTURE
The relative abundance of each bacterial taxa is estimated
Combined with quantitative PCR of the 16S rRNA gene, estimates of absolute abundance can be obtained for each bacterial taxa HOW TO STUDY THE MICROBIOME
Diferent questions – DiferentC approaches
What can they do? (Metagenome) Metagenomics determines the microbiome genes and genomes content by sequencing total genomic DNA C Access composition and abundance of the microbiome Understand the functional potential of a microbiome from reconstructed genomes of membersCST I of the microbiotaCST V CST III METAGENOMICS - COMPOSITION/FUNCTION
Cost of metagenomics is almost equivalent to that of 16S rRNA gene sequencing
Metagenomics afords compositional/structural profling microbiota
Metagenomics afords functional profling of the microbiome
Less biased approach to compositional profling HOW TO STUDY THE MICROBIOME
Diferent questions – DiferentC approaches
What are they doing? (and the host) Metatranscriptomics - Determine the microbiome expressed genes content by sequencing cDNA
Metaproteomics – Determine theC protein content (identity) of a microbiome/host using mass spectrometry Metabolomics – Determine the metabolitesCST I compositionCST V of a CST III microbiome using mass spectrometry. The output of microbial/ host metabolisms METAGENOMICS IDENTIFIES HIGH WITHIN-COMMUNITY
INTRASPECIES DIVERSITY virgo.igs.umaryland.edu
Comparative analysis of 1,507 vaginal metagenomes and vaginal bacteria genomes Number of non-redundant genes Number of non-redundant
Genomes Metagenomes Metagenomes containing L. crispatus & genomes from isolates
Ma et al.. Nature Communications 2020
Genomes from isolates METAGENOMICS / METATRANSCRIPTOMICS
Ma et al.. Nature Communications 2020 IN SUMMARY…
Studying the microbiome is answeringC …
Who’s there? Metataxonomic profling (compositional/structural changes)
What are they doing? Functional proC fling (functional changes) What does this all mean? Complex statistical and modeling analyses CST I CST V CST III (Establishing statistical support for observed changes) ACKNOWLEDGEMENTS
github.com/ravel-lab/VALENCIA Bing Ma Michael France Johanna Holm Pawel Gajer Vonetta Edwards Steve Smith
virgo.igs.umaryland.edu