Module 16- T1D Only Flashcards
Between 2001 and 2009 there was a … increase in T1D for people under 20
21%
Contribution of microbial species to disease
Metabolic network + Dynamic equilibrium with themselves and our cells + Innate and acquired defensive systems imbalanced
Kill Beta cells
Induced T and B cells
Proof that microbes play role in T1D
Provide antibiotics –> No disease
Leaky gut and T1D steps
Antigen gets through leaky gut –> activate APC in lamina propria –> cytokine release –> T and B cell activation –> kill beta cells
BB-DR rats
Biobreathing drug resistant predisposed to diabetes but do not get it
BB-DP rats
Biobreathing diabetes prone rats that get diabetes between day 17 and 110
Microbes in BB-DP rats
Bacteroides - Xanthomonas + Acinetobacter
BB-DR rats
Lactobacillus- Clostridium, Flexibacter, Porphyromonas
454-Pyrosequencing
Less diverse microbiota in rats over time and less richness
Criteria for selection of microbiota transplant of Lactobacillus
From 500 colonies –> Found in humans, probiotic properties reported (tolerance to bile and acid), no antagonistic effect to other Lactobacillus species
Onset of T1D
Days 69-110 –> gibe bacteria orally pre-weaning or post-weaing (immediate or after start of solid food) –> only difference in post weaning
L. Johnsonii changes in microbiota bacterial counts?
No differences
RT-PCR
Culture Independent method to see change in microbiota
RT-PCR results
More Lactobacillus in healthy and Enterococci in diabetic
Changes in mucosal integrity/architecture
Measure villi and necrosis but saw no differences
Tight junctions
Claudin (and occludin) higher –> Ljo fed
L. johnsonii changes
Tight junction proteins and cytokines
Cytokines changes by L. johnsonii
IFNY (and TNFa); lower expression of pro cytokines
Addition of TNF-a to epi cells and look at cytokine production
No effect at higher concentrations but does induce immune system by chemokine that prevent later IR
L. Johnsonii modulate IR through
TLR7 and TL9; mostly through DNA molecules
Mech Ljo use to modulate IR
Polarizing-tolerizing mechanism
TRL9 induction gives
Increased paneth cells that secrete AM molecules found at the bottom of crypts –> more secretion of AM molecules
Phases of T1D testing
Proof of concept –> Phase one on healthy –> Phase two on disease –> phase 3 on kids to prevent onset
Placebo
Dried milk
Study Design
Baseline –> Ljo N6.2 or placebo –> wash out –> look at blood and stool samples
Ljo led to
Significant decrease of symptoms in questionnaire including anxiety and epidermal syndrome
Immunotyping of trial
Cell types
Cell Types that increased upon supplementation
Monocytes and NK cells and CD8 cells
Cell types that were modified
T cell subsets (decreased)
CD8 cells…
Start to decrease after wash out
Th types activation
Th1 after 8 weeks and Th17 after 12 weeks
In healthy subjects Ljo led to more
Circulating IgA
Changes in microbiome
Larger between each individual than between treatments
Risk of Ljo
None in healthy
Ljo suppresses
GI distress syndrome and cephalic syndrome
Altered metabolies
Tryptophan pathway metabolites after 12 weeks with increasing LAB over time
Th subtype mainly increased
Th1
