Project description:Vaccine research today is focused on using safer, highly purified or recombinant antigens with poor immunogenicity, which has created a need for potent adjuvants. Rational design of effective and safe mucosal adjuvants for human use necessitates a thorough understanding of the mode of action of successful candidate adjuvants. We used microarray to comprehend the molecular signatures of mucosal adjuvants in the mouse vagina. The adjuvants studied, CpG-ODN and α-GalCer have previously been shown to be potent mucosal adjuvants in mice when administrered together with a glycoprotein from HSV-2. Two individual experiments were performed, called ES1 and ES2, each experiment contained 4 groups of mice. All mice were pre-treated with progesteron (DP) before intravaginally recieveing either CpG ODN, alpha-GalCer or their respective buffers, PBS and PBS/Tween. Vaginas were excised at 3 different time-points; 4h, 24h and 48h following adjuvant delivery.
Project description:National screening programs use dried blood specimens to detect abnormal metabolism or aberrant protein function in infants shortly after birth, thus identifying disorders that are not clinically evident in the newborn period. Gut microbiota metabolites and immunological acute phase proteins are capable of revealing potential immune aberrations. Microbial metabolites interact with xenobiotic receptors (i.e., aryl hydrocarbon and pregnane-X) and maintain gastrointestinal tissue health, supported by acute-phase proteins, functioning as sensors of microbial immunomodulation and homeostasis. The delivery mode (vaginal or cesarean section) shapes the microbial colonization, which substantially modulates both the immune system's response and mucosal homeostasis.
This study profiled microbial metabolites of the kynurenine and tryptophan pathway and acute phase proteins in 134 neonatal dried blood specimens. We newly established neonatal blood levels of the aryl hydrocarbon receptor microbial ligands (indole-3-aldehyde, indole-3-butyric acid, and indole-3-acetamide) on the second day of life. Furthermore, we observed divergent microbial metabolic profiles in neonates born vaginally or via cesarean section, hypothesizing potential microbial immunomodulatory influence. In summary, these findings suggest the supportive role of human gut microbiota in developing and maintaining immune system homeostasis.
Project description:The mammalian gastrointestinal tract contains a diverse ecosystem of microbial species collectively making up the gut microbiome. Emerging evidence highlights a critical relationship between gut microbiota and neurocognitive development. Consumption of unhealthy yet palatable dietary factors associated with obesity and metabolic dysfunction (e.g., saturated fat, added sugar) produces microbiota dysbiosis and negatively impacts neurocognitive function, particularly when consumed during early life developmental periods. Here we explore whether excessive early life consumption of added sugars negatively impacts neurocognitive development via the gut microbiome. Using a rodent model of habitual sugar-sweetened beverage (SSB) consumption during the adolescent stage of development, we first show that excessive early life sugar intake impairs hippocampal-dependent memory function when tested during adulthood while preserving other neurocognitive domains. Gut microbiome genomic sequencing analyses reveal that early life SSB consumption alters the abundance of various bacterial populations, including elevations in operational taxonomic units within the genus Parabacteroides (P. distasonis and P. johnsonii) whose abundance negatively correlated with memory task performance. Additional results reveal that in vivo Parabacteroides enrichment of cultured P. distasonis and P. johnsonii bacterial species in adolescent rats severely impairs memory function during adulthood. Hippocampus transcriptome analyses identify gene expression alterations in neurotransmitter synaptic signaling, intracellular kinase signaling, metabolic function, neurodegenerative disease, and dopaminergic synaptic signaling-associated pathways as potential mechanisms linking microbiome outcomes with memory impairment. Collectively these results identify microbiota dysbiosis as a mechanism through which early life unhealthy dietary patterns negatively impact neurocognitive outcomes.
Project description:Vaccine research today is focused on using safer, highly purified or recombinant antigens with poor immunogenicity, which has created a need for potent adjuvants. Rational design of effective and safe mucosal adjuvants for human use necessitates a thorough understanding of the mode of action of successful candidate adjuvants. We used microarray to comprehend the molecular signatures of mucosal adjuvants in the mouse vagina. The adjuvants studied, CpG-ODN and α-GalCer have previously been shown to be potent mucosal adjuvants in mice when administrered together with a glycoprotein from HSV-2.
Project description:Background - Prepregnancy overweight and obesity promote deleterious health impacts on both mothers during pregnancy and the offspring. Significant changes in the maternal peripheral blood mononuclear cells (PBMCs) gene expression due to obesity are well-known. However, during pregnancy the impact of overweight on immune cell gene expression and its association with maternal and infant outcomes is not well explored. Methods – Blood samples were collected from healthy normal weight (NW, BMI 18.5-24.9) or overweight (OW, BMI 25-29.9) 2nd parity pregnant women at 12, 24 and 36 weeks of pregnancy. PBMCs were isolated from the blood and subjected to mRNA sequencing. Maternal and infant microbiota were analyzed by 16S rRNA gene sequencing. Integrative multi-omics data analysis was performed to evaluate the association of gene expression with maternal diet, gut microbiota, milk composition, and infant gut microbiota. Results - Gene expression analysis revealed that 453 genes were differentially expressed in the OW women compared to NW women at 12 weeks of pregnancy, out of which 354 were upregulated and 99 were downregulated. Several up-regulated genes in the OW group were enriched in inflammatory, chemokine-mediated signaling and regulation of interleukin-8 production-related pathways. At 36 weeks of pregnancy healthy eating index score was positively associated with several genes that include, DTD1, ELOC, GALNT8, ITGA6-AS1, KRT17P2, NPW, POT1-AS1 and RPL26. In addition, at 36 weeks of pregnancy, genes involved in adipocyte functions, such as NG2 and SMTNL1, were negatively correlated to human milk 2’FL and total fucosylated oligosaccharides content collected at 1 month postnatally. Furthermore, infant Akkermansia was positively associated with maternal PBMC anti-inflammatory genes that include CPS1 and RAB7B, at 12 and 36 weeks of pregnancy. Conclusions – These findings suggest that prepregnancy overweight impacts the immune cell gene expression profile, particularly at 12 weeks of pregnancy. Further, deciphering the complex association of PBMC’s gene expression levels with maternal gut microbiome and milk composition and infant gut microbiome may aid in developing strategies to mitigate obesity-mediated effects.
Project description:Birth mode has been implicated as a major factor influencing neonatal gut microbiome development, and it has been assumed that lack of exposure to the maternal vaginal microbiome is responsible for gut dysbiosis among caesarean-delivered infants. Consequently, practices to correct dysbiotic gut microbiomes, such as vaginal seeding, have arisen while the effect of the maternal vaginal microbiome on that of the infant gut remains unknown. We conducted a longitudinal, prospective cohort study of 621 Canadian pregnant women and their newborn infants and collected pre-delivery maternal vaginal swabs and infant stool samples at 10-days and 3-months of life. Using cpn60-based amplicon sequencing, we defined vaginal and stool microbiome profiles and evaluated the effect of maternal vaginal microbiome composition and various clinical variables on the development of the infant stool microbiome. Infant stool microbiomes showed significant differences in composition by delivery mode at 10-days postpartum; however, this effect could not be explained by maternal vaginal microbiome composition and was vastly reduced by 3 months. Vaginal microbiome clusters were distributed across infant stool clusters in proportion to their frequency in the overall maternal population, indicating independence of the two communities. Intrapartum antibiotic administration was identified as a confounder of infant stool microbiome differences and was associated with lower abundances of Escherichia coli, Bacteroides vulgatus, Bifidobacterium longum and Parabacteroides distasonis. Our findings demonstrate that maternal vaginal microbiome composition at delivery does not affect infant stool microbiome composition and development, suggesting that practices to amend infant stool microbiome composition focus factors other than maternal vaginal microbes.