Poster Abstracts - S618
Articles
Association between dysbiosis of the vaginal microbiota and bacterial infections
Identification: ., Apoorva
Credits: None available.
Association between dysbiosis of the vaginal microbiota and bacterial infections
Apoorva1, Somesh Gupta1*, Seema Sood2, Benu Dhawan2, Garima Kacchawa3, A.K.Saxena4
Departments of 1Dermatology and Venereology,2Microbiology, 3Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India, 4Dermatology and S.T.D Department, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India
*Corresponding author
Introduction: A healthy vaginal flora is composed of facultative and strict anaerobes with Lactobacillus species being predominant. Decrease in the protective lactobacilli and concomitant increase in anaerobic bacteria leads to bacterial vaginosis (BV). Alterations in the composition of the vaginal flora is associated with adverse reproductive outcomes and acquisition and transmission of sexually transmitted infections (STIs) e.g. Neisseria gonorrhea, Chlamydia trachomatis, Mycoplasma species and human immunodeficiency virus (HIV).
Aim & Objectives: The study was conducted to assess the prevalence of bacterial infections of vaginal tract in women with abnormal flora and its correlation with severity of dysbiosis.
MATERIALS & METHODS: Thirty five sexually active non-pregnant women between 18-45 years of age who presented with self reported symptoms of vaginitis (vaginal discharge/ genital itching/ genital burning/ lower abdominal pain) were included in the study. Vaginal swab specimens were collected from the lateral wall of the vagina and abundance of various bacterial morphotypes was assessed by microscopic evaluation of Gram stained smears using the Nugent scoring method for diagnosis of BV. Samples with a score of ≥4 suggestive of dysbiosis were processed further for polymerase chain reaction (PCR) based detection of Neisseria gonorrhea, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis and Ureaplasma urealyticum.
Results: Nugent's score ≥4 was reported in 15 (42.86%) out of 35 women enrolled in the study. Among these women with dysbiosis, Chlamydia trachomatis was detected in 1 (6.67%), Mycoplasma hominis in 2 (13.33%) and Ureaplasma urealyticum in 1 (6.6.7%) out of 15 samples. None of these 15 samples were positive for Neisseria gonorrhea and Mycoplasma genitalium. Co-infection with other bacteria was found in BV positive women.
Conclusion: Vaginal dysbiosis may be associated with other bacterial infections and therefore regular screening for co-existing pathogens contributing to STIs should be encouraged.
Apoorva1, Somesh Gupta1*, Seema Sood2, Benu Dhawan2, Garima Kacchawa3, A.K.Saxena4
Departments of 1Dermatology and Venereology,2Microbiology, 3Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India, 4Dermatology and S.T.D Department, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India
*Corresponding author
Introduction: A healthy vaginal flora is composed of facultative and strict anaerobes with Lactobacillus species being predominant. Decrease in the protective lactobacilli and concomitant increase in anaerobic bacteria leads to bacterial vaginosis (BV). Alterations in the composition of the vaginal flora is associated with adverse reproductive outcomes and acquisition and transmission of sexually transmitted infections (STIs) e.g. Neisseria gonorrhea, Chlamydia trachomatis, Mycoplasma species and human immunodeficiency virus (HIV).
Aim & Objectives: The study was conducted to assess the prevalence of bacterial infections of vaginal tract in women with abnormal flora and its correlation with severity of dysbiosis.
MATERIALS & METHODS: Thirty five sexually active non-pregnant women between 18-45 years of age who presented with self reported symptoms of vaginitis (vaginal discharge/ genital itching/ genital burning/ lower abdominal pain) were included in the study. Vaginal swab specimens were collected from the lateral wall of the vagina and abundance of various bacterial morphotypes was assessed by microscopic evaluation of Gram stained smears using the Nugent scoring method for diagnosis of BV. Samples with a score of ≥4 suggestive of dysbiosis were processed further for polymerase chain reaction (PCR) based detection of Neisseria gonorrhea, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis and Ureaplasma urealyticum.
Results: Nugent's score ≥4 was reported in 15 (42.86%) out of 35 women enrolled in the study. Among these women with dysbiosis, Chlamydia trachomatis was detected in 1 (6.67%), Mycoplasma hominis in 2 (13.33%) and Ureaplasma urealyticum in 1 (6.6.7%) out of 15 samples. None of these 15 samples were positive for Neisseria gonorrhea and Mycoplasma genitalium. Co-infection with other bacteria was found in BV positive women.
Conclusion: Vaginal dysbiosis may be associated with other bacterial infections and therefore regular screening for co-existing pathogens contributing to STIs should be encouraged.
Cervicovaginal cells from HIV-infected South African women express higher levels of genes involved in microbial pattern recognition and inflammatory pathways than peripheral blood mononuclear cells
Identification: Abrahams, Andrea
Credits: None available.
Cervicovaginal cells from HIV-infected South African women express higher levels of genes involved in microbial pattern recognition and inflammatory pathways than peripheral blood mononuclear cells
Andrea Gillian Abrahams1*, Arghavan Alisoltanidehkordi1, Jason Skinner3, Damien Chaussabel3,4, Jo-Ann S. Passmore1,2,6, Lindi Masson1,2*
1Institute of Infectious Disease and Molecular Medicine (IDM), University of Cape Town, South Africa; 2Centre for the AIDS Programme of Research in South Africa (CAPRISA), South Africa; 3Baylor Institute for Immunology Research, Texas, USA; 4Sidra Medicine, Qatar; 6National Health Laboratory Services, South Africa.
*Contributed equally
The interplay between the female genital tract (FGT) microbiome and immune system is critical for defence against pathogens, while maintaining tolerance to commensal bacteria and allogenic semen. However, FGT inflammation increases risk of HIV acquisition, mother-to-child transmission and transmission to partners. Using transcriptomics, we compared the expression of genes involved in inflammatory signalling pathways between cervical mononucleocytes (CMC) and blood mononucleocytes (PBMC) from HIV-infected women.
Cervical cytobrushes and blood were collected from HIV-infected South African women on antiretroviral therapy (ART), cells were isolated and mRNA was extracted. Clinical signs and symptoms of genital infections were recorded at the time of sampling. Gene expression was evaluated in CMCs [RNA Integrity Number (RIN): 5.3-8.4] and matching PBMCs (RIN: 8.6-9.8) using Illumina HumanHT-12 v3 Expression BeadChip. Data analysis was performed using R studio and DAVID NIH.
A total of 205 genes were differentially expressed between CMCs and PBMCs, with 136 genes upregulated (logFC≥1.5) and 69 genes downregulated (logFC≤-1.5). Although none of the women had clinical signs of a genital infection, genes involved in inflammatory signalling pathways, Nuclear Factor-kappa B, Tumor necrosis factor, Toll-like receptor and NOD-like receptor signalling were significantly upregulated in CMCs compared to PBMCs (adjusted p=0.002, p=0.026, p=0.026, p=0.044, respectively). Key genes in these pathways were IL-1β, NFkBI and IL-8 (p=0.008, p=0.010, p=0.014, respectively).
In conclusion, we found that genes involved in inflammatory signalling pathways were upregulated in the FGT compared to blood of HIV-infected women, that may influence HIV shedding and transmission.
Andrea Gillian Abrahams1*, Arghavan Alisoltanidehkordi1, Jason Skinner3, Damien Chaussabel3,4, Jo-Ann S. Passmore1,2,6, Lindi Masson1,2*
1Institute of Infectious Disease and Molecular Medicine (IDM), University of Cape Town, South Africa; 2Centre for the AIDS Programme of Research in South Africa (CAPRISA), South Africa; 3Baylor Institute for Immunology Research, Texas, USA; 4Sidra Medicine, Qatar; 6National Health Laboratory Services, South Africa.
*Contributed equally
The interplay between the female genital tract (FGT) microbiome and immune system is critical for defence against pathogens, while maintaining tolerance to commensal bacteria and allogenic semen. However, FGT inflammation increases risk of HIV acquisition, mother-to-child transmission and transmission to partners. Using transcriptomics, we compared the expression of genes involved in inflammatory signalling pathways between cervical mononucleocytes (CMC) and blood mononucleocytes (PBMC) from HIV-infected women.
Cervical cytobrushes and blood were collected from HIV-infected South African women on antiretroviral therapy (ART), cells were isolated and mRNA was extracted. Clinical signs and symptoms of genital infections were recorded at the time of sampling. Gene expression was evaluated in CMCs [RNA Integrity Number (RIN): 5.3-8.4] and matching PBMCs (RIN: 8.6-9.8) using Illumina HumanHT-12 v3 Expression BeadChip. Data analysis was performed using R studio and DAVID NIH.
A total of 205 genes were differentially expressed between CMCs and PBMCs, with 136 genes upregulated (logFC≥1.5) and 69 genes downregulated (logFC≤-1.5). Although none of the women had clinical signs of a genital infection, genes involved in inflammatory signalling pathways, Nuclear Factor-kappa B, Tumor necrosis factor, Toll-like receptor and NOD-like receptor signalling were significantly upregulated in CMCs compared to PBMCs (adjusted p=0.002, p=0.026, p=0.026, p=0.044, respectively). Key genes in these pathways were IL-1β, NFkBI and IL-8 (p=0.008, p=0.010, p=0.014, respectively).
In conclusion, we found that genes involved in inflammatory signalling pathways were upregulated in the FGT compared to blood of HIV-infected women, that may influence HIV shedding and transmission.
Lifestyle and the Environment Influence the Structure and Predicted Function of the Gut Microbiota in Nomadic Fulanis
Identification: Afolayan, Ayorinde
Credits: None available.
Lifestyle and the Environment Influence the Structure and Predicted Function of the Gut Microbiota in Nomadic Fulanis
Ayorinde Afolayan1, Funmilola Ayeni1*, and Christoph Hoegenauer1*
1Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Oyo State, Nigeria; 2Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
*Corresponding author
The human gut microbiota plays a major role in the normal functioning of the human body. Lifestyle affects the gut microbiota. However, its contribution on the gut microbiota of vulnerable populations in Nigeria is relatively unknown. This study focused on the effect of nomadic lifestyle of the Fulanis on their gut microbiota.
Human faecal and environmental samples (soil and water) were obtained from nomadic Fulanis (Pabaman-shanu village, Plateau State; n = 28) and non-Fulanis (Lamingo, Jos n = 22). Bovine milk was obtained from the Fulanis. The DNA of all samples were extracted, followed by PCR amplification of the V4 region of 16S rRNA gene, library preparation, and sequencing with Illumina MiSeq. From the generated raw sequence reads, the gut microbiota of Fulanis and non-Fulanis were compared for diversity by QIIME, functional profile by PICRUSt, unique structural and predicted functional biomarkers by LEfSe, and relative abundance of predicted pathogens by BugBase.
The Fulanis had lower alpha diversity. Differential phyla include Bacteroidetes (Prevotella) in the Fulanis, and Firmicutes (Ruminococcus) in the non-Fulanis. Lipopolysaccharide biosynthesis, Vibrio cholerae pathogenic cycle, and Glutathione metabolism were enriched in the Fulanis, while methane metabolism and fructose and mannose metabolism were overrepresented in the non-Fulanis, suggesting the impact of dietary and hygiene habits on the gut microbiota. A higher abundance of potential gut pathogens were observed in the Fulani. Proteobacteria is more abundant in soil (53.3% versus 31.4% for non-Fulanis) and drinking water (94% versus 59% for non-Fulanis) from the Fulani community. The two sole phyla in milk are the Firmicutes (90%) and Proteobacteria (10%).
The reduced gut microbiota alpha diversity is a reflection of the Fulani's lifestyle, which increases vulnerability to diseases. Differential taxa and metabolic pathways could serve as potential markers for health risk of similar study groups.
Ayorinde Afolayan1, Funmilola Ayeni1*, and Christoph Hoegenauer1*
1Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Oyo State, Nigeria; 2Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
*Corresponding author
The human gut microbiota plays a major role in the normal functioning of the human body. Lifestyle affects the gut microbiota. However, its contribution on the gut microbiota of vulnerable populations in Nigeria is relatively unknown. This study focused on the effect of nomadic lifestyle of the Fulanis on their gut microbiota.
Human faecal and environmental samples (soil and water) were obtained from nomadic Fulanis (Pabaman-shanu village, Plateau State; n = 28) and non-Fulanis (Lamingo, Jos n = 22). Bovine milk was obtained from the Fulanis. The DNA of all samples were extracted, followed by PCR amplification of the V4 region of 16S rRNA gene, library preparation, and sequencing with Illumina MiSeq. From the generated raw sequence reads, the gut microbiota of Fulanis and non-Fulanis were compared for diversity by QIIME, functional profile by PICRUSt, unique structural and predicted functional biomarkers by LEfSe, and relative abundance of predicted pathogens by BugBase.
The Fulanis had lower alpha diversity. Differential phyla include Bacteroidetes (Prevotella) in the Fulanis, and Firmicutes (Ruminococcus) in the non-Fulanis. Lipopolysaccharide biosynthesis, Vibrio cholerae pathogenic cycle, and Glutathione metabolism were enriched in the Fulanis, while methane metabolism and fructose and mannose metabolism were overrepresented in the non-Fulanis, suggesting the impact of dietary and hygiene habits on the gut microbiota. A higher abundance of potential gut pathogens were observed in the Fulani. Proteobacteria is more abundant in soil (53.3% versus 31.4% for non-Fulanis) and drinking water (94% versus 59% for non-Fulanis) from the Fulani community. The two sole phyla in milk are the Firmicutes (90%) and Proteobacteria (10%).
The reduced gut microbiota alpha diversity is a reflection of the Fulani's lifestyle, which increases vulnerability to diseases. Differential taxa and metabolic pathways could serve as potential markers for health risk of similar study groups.
Sialoglycan foraging drives mutualism between Fusobacterium nucleatum and the vaginal microbiota
Identification: Agarwal, Kavita
Credits: None available.
Sialoglycan foraging drives mutualism between Fusobacterium nucleatum and the vaginal microbiota
Kavita Agarwal1, Lloyd Robinson1, Justin Perry1, Lynne Foster1, Hueylie Lin1, Brett Tortelli1, Nicole Gilbert2, Warren Lewis1, Amanda Lewis1,2*
Departments of 1Molecular Microbiology & 2Obstetrics and Gynecology, Washington University in St. Louis
*Corresponding Author
Bacterial vaginosis (BV), a common vaginal dysbiosis, is characterized by low numbers of healthy Lactobacillus spp. and the overgrowth of diverse anaerobic bacteria. Women with BV are more likely to be vaginally colonized with Fusobacterium nucleatum, a pathogen frequently isolated from amniotic fluid in cases of pre-term birth. However, mechanisms employed by F. nucleatum during vaginal colonization have not been studied. A characteristic biochemical feature of BV is the presence of vaginal sialidase activity. Sialidases are enzymes that can liberate sialic acids from oligosaccharide chains decorating mammalian cell surface glyco-conjugates. While F. nucleatum does not produce its own sialidase it is often found colonizing with other sialidase producing bacteria, which could allow metabolic cross feeding of this opportunistic pathogen. Therefore, we hypothesize that sialic acid catabolism may facilitate vaginal colonization by F. nucleatum in the presence of sialidase activity. Our studies show that sialic acids are depleted from the vaginal epithelial cell surface, and free sialic acids are present at significantly higher concentration in vaginal fluids of women with BV. We also show that F. nucleatum can uptake and metabolize free sialic acid liberated by sialidases from BV associated pathogens such as Gardnerella vaginalis. Studies using a mouse vaginal colonization model revealed that F. nucleatum mutant defective in sialic acid consumption cleared significantly faster, than the wild-type counterpart, from mouse vaginas with sialidase producing microbiota. Interestingly, further studies revealed that F. nucleatum also provides reciprocal benefits to the sialidase producing bacteria in vaginal microbial communities, resulting in higher levels of sialidase activity and increased numbers of sialidase producers such as G. vaginalis. Taken together, these data provide the first mechanistic glimpse of how sialidase activity, one of the hallmark features of BV, may help to create a more hospitable environment for potential reproductive tract pathogens such as F. nucleatum.
Kavita Agarwal1, Lloyd Robinson1, Justin Perry1, Lynne Foster1, Hueylie Lin1, Brett Tortelli1, Nicole Gilbert2, Warren Lewis1, Amanda Lewis1,2*
Departments of 1Molecular Microbiology & 2Obstetrics and Gynecology, Washington University in St. Louis
*Corresponding Author
Bacterial vaginosis (BV), a common vaginal dysbiosis, is characterized by low numbers of healthy Lactobacillus spp. and the overgrowth of diverse anaerobic bacteria. Women with BV are more likely to be vaginally colonized with Fusobacterium nucleatum, a pathogen frequently isolated from amniotic fluid in cases of pre-term birth. However, mechanisms employed by F. nucleatum during vaginal colonization have not been studied. A characteristic biochemical feature of BV is the presence of vaginal sialidase activity. Sialidases are enzymes that can liberate sialic acids from oligosaccharide chains decorating mammalian cell surface glyco-conjugates. While F. nucleatum does not produce its own sialidase it is often found colonizing with other sialidase producing bacteria, which could allow metabolic cross feeding of this opportunistic pathogen. Therefore, we hypothesize that sialic acid catabolism may facilitate vaginal colonization by F. nucleatum in the presence of sialidase activity. Our studies show that sialic acids are depleted from the vaginal epithelial cell surface, and free sialic acids are present at significantly higher concentration in vaginal fluids of women with BV. We also show that F. nucleatum can uptake and metabolize free sialic acid liberated by sialidases from BV associated pathogens such as Gardnerella vaginalis. Studies using a mouse vaginal colonization model revealed that F. nucleatum mutant defective in sialic acid consumption cleared significantly faster, than the wild-type counterpart, from mouse vaginas with sialidase producing microbiota. Interestingly, further studies revealed that F. nucleatum also provides reciprocal benefits to the sialidase producing bacteria in vaginal microbial communities, resulting in higher levels of sialidase activity and increased numbers of sialidase producers such as G. vaginalis. Taken together, these data provide the first mechanistic glimpse of how sialidase activity, one of the hallmark features of BV, may help to create a more hospitable environment for potential reproductive tract pathogens such as F. nucleatum.
Placental Origins of the Fetal Lung Microbiome
Identification: Al Alam, Denise
Credits: None available.
Placental Origins of the Fetal Lung Microbiome
Denise Al Alam, Soula Danopoulos, Matthew Thornton, Brendan Grubbs, David Warburton, Timothy Wang, Namasivayam Ambalavanan, Charitharth Vivek Lal
The myth of the sterile fetus has been challenged by several recent studies showing evidence of microbial DNA, microbial products, and occasionally living bacteria within the placenta and amniotic fluid. Moreover, recent studies have confirmed the presence of a diverse microbiome in the human lung, including neonates, but the origin of the microbiome remains elusive. Herein, we aimed to investigate the presence and origin of a human fetal lung microbiome.
Eighteen de-identified human fetal lung tissues from 11 weeks gestation (1st trimester) to 20 weeks gestation (2nd trimester), along with 10 matched placentas, were collected following sterile and standardized clinical procedures. Samples were processed and microbiome analysis was conducted on each sample. Bacterial DNA was detected and characterized in all fetal lung and placenta samples. Principal coordinates analysis (PCoA) plot analysis of the human fetal lung microbiomes split into two separate groups (11-15 week gestation versus 16-20 week gestation) demonstrated increasing beta diversity. Our analysis of the distance and clustering of the samples (closer clustering signifying shared larger proportion of phylogenetic tree) showed that there was a significant change in the microbiome diversity between the two gestational groups. This suggests that the lung microbiome diversity changes as gestational age of the human fetus increases. To compare the microbiota of fetal lung and placenta, we analyzed 10 'matched pair' sets. Overall analysis of the bacterial taxa distribution and diversity showed striking similarity in the microbiota of matched lungs and placentas. These results show that the fetal lung microbiome is extremely similar to the placental microbiome in matched pairs. In this study, we analyzed the microbiomes of human fetal lung as early as the first trimester and corresponding placentas. A major novel finding was the existence of a human fetal microbiome signature, as early as the first trimester. In conclusion, our analysis shows that a placental microbiome indeed exists and that it bears striking similarity to the human fetal lung microbiome based on overall microbiome analysis, as well as alpha and beta diversities.
Denise Al Alam, Soula Danopoulos, Matthew Thornton, Brendan Grubbs, David Warburton, Timothy Wang, Namasivayam Ambalavanan, Charitharth Vivek Lal
The myth of the sterile fetus has been challenged by several recent studies showing evidence of microbial DNA, microbial products, and occasionally living bacteria within the placenta and amniotic fluid. Moreover, recent studies have confirmed the presence of a diverse microbiome in the human lung, including neonates, but the origin of the microbiome remains elusive. Herein, we aimed to investigate the presence and origin of a human fetal lung microbiome.
Eighteen de-identified human fetal lung tissues from 11 weeks gestation (1st trimester) to 20 weeks gestation (2nd trimester), along with 10 matched placentas, were collected following sterile and standardized clinical procedures. Samples were processed and microbiome analysis was conducted on each sample. Bacterial DNA was detected and characterized in all fetal lung and placenta samples. Principal coordinates analysis (PCoA) plot analysis of the human fetal lung microbiomes split into two separate groups (11-15 week gestation versus 16-20 week gestation) demonstrated increasing beta diversity. Our analysis of the distance and clustering of the samples (closer clustering signifying shared larger proportion of phylogenetic tree) showed that there was a significant change in the microbiome diversity between the two gestational groups. This suggests that the lung microbiome diversity changes as gestational age of the human fetus increases. To compare the microbiota of fetal lung and placenta, we analyzed 10 'matched pair' sets. Overall analysis of the bacterial taxa distribution and diversity showed striking similarity in the microbiota of matched lungs and placentas. These results show that the fetal lung microbiome is extremely similar to the placental microbiome in matched pairs. In this study, we analyzed the microbiomes of human fetal lung as early as the first trimester and corresponding placentas. A major novel finding was the existence of a human fetal microbiome signature, as early as the first trimester. In conclusion, our analysis shows that a placental microbiome indeed exists and that it bears striking similarity to the human fetal lung microbiome based on overall microbiome analysis, as well as alpha and beta diversities.