Latest microbiome science news

Simon McGrath

Microbiome image courtesy of Steve Gschmeissner

Microbiome image courtesy of Steve Gschmeissner

The number of Microbiome research studies is exploding: Google scholar lists 17,000 hits for papers on the microbiome published this year so far. Here are some recent gems:

New ME/CFS microbiome study

A small and very interesting new microbiome study from Dr Maureen Hanson at Cornell University suggests ME/CFS patients have gut bacteria associated with inflammation and immune activation. Dr Ian Lipkin is pursuing his microbiome study precisely because he thinks the microbiome could be behind the immune activation that he and other researchers are finding in ME/CFS patients.
Dr Mady Hornig is very interested in this new microbiome study and has been in contact with Dr Hanson. The research we are trying to crowdfund will build perfectly on great work like Dr Hanson’s. As the largest and most rigorous ME/CFS microbiome study to date, this crowdfunded microbiome research study will bring this all up to a new level and also analyse differently. With a larger cohort and more specific criteria of diagnosis within a larger geographical location: Dr.s Lipkin and Hornig will be looking at a much larger range of organisms, bacteria, fungi and Viruses and be analysing the immune system activation with respect to a wide variety of cytokines. It is really exciting discovery type work and is about the immune system and possible autoimmunity just as much as pathogenic behaving bacteria and organisms.Dr Hanson’s Study IACFS/ME poster abstracts:
“Altered Gut Microbiome in ME/CFS Patients”

Methods.
We characterized the gut bacteria of a cohort of 48 patients with ME/CFS and 36 healthy controls from New York City (via sequencing 16S rRNA genes). All patients fulfilled the Fukuda criteria for diagnosis of CFS. We also measured three markers of inflammation in blood plasma: lipopolysaccharide (LPS), soluble CD14 (sCD14) and lactoferrin (LF)

Results.
In both cases and controls, the most represented phyla were Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria.

Statistical analysis revealed significant fewer members of the Bacteroidetes and significantly more members of the Firmicutes in the patient population – also reported in Crohn’s disease and acute ulcerative colitis (both are inflammatory bowel diseases).

In particular, there were fewer butyrate-producer Roseburia faecis in ME/CFS patients
(note: butyrate is a key molecule produced by some gut microbes that helps boost immune tolerance and reduce inflammation. Low levels of butyrate-producing bacteria are suspected to play a critical role in some inflammatory bowel diseases.)

There was an increase of inflammatory Ruminococcus spp. (p < 0.001, q = 0.004) The amounts of inflammatory markers LPS, sCD14 and LF in plasma fell within normal ranges in both patients and controls. Our data do not corroborate prior reports of significantly higher levels of Lactonifactor, Alistipes and Enterococci in the feces of patients.

Conclusion.
Subjects with ME/CFS in our cohort have a shift in overall microbial composition in comparison to healthy donors, a finding also characteristic of patients with inflammatory bowel disease.

Our analyses highlight the contrast between the distribution of anti-inflammatory species, such as Roseburia species, which are more prevalent in healthy individuals, and potentially pro-inflammatory Ruminococcaceae, which are associated with irritable bowel syndrome and found to be more frequent in ME/CFS cases. Despite the differences in gut microbiome, three inflammatory markers did not differ between patients and controls in plasma.

Whether deliberate manipulation of the composition of the gut microbiome in ME/CFS patients may ameliorate symptoms in some patients remains to be investigated.

Top researchers talk microbiome and the brain

In a podcast last week, two top microbiome researchers focus on the emerging evidence that bacteria in your gut can send messages to the brain.
The researchers mention that, compared with research on the microbiome and the brain, work linking the gut microbiome to immune system problems is much more established. The link is hardly surprising given that, as they point out, nearly 70% of our B-cells and T-cells are based in and around the gut wall.

Microbiome and the immune system connection – more evidence

A recent paper focuses on the potential link between the microbiome and autoimmunity in Multiple Sclerosis. From our point of view, what’s interesting is that the paper reviews the considerable evidence that microbiome plays a key role in healthy immune system functioning, as well as the evidence that problems in the microbiome are associated with problems in the immune system. These problems are seen in the levels of critical immune messenger molecules called cytokines.
Both Dr Jose Montoya, and Drs Ian Lipkin & Mady Hornig, have recently completed large studies that found significant differences between patients and controls in certain cytokines (unpublished results reported at Stanford Symposium in March).

Gut microbes could stop peanut allergies

Finally, a new study published in a top journal shows that in mice the gut microbiome plays a role in peanut allergies – and the right bacteria could provide a treatment. What makes this study so interesting is that first it showed that the ‘right’ bacteria (Clostridia) can protect mice against developing peanut allergies – which is impressive. Then the researchers went on to show these bacteria work this trick: “acting through certain immune cells, the bacteria helped keep peanut proteins that can cause allergic reactions out of the bloodstream”. This research opens up the possibility of using bacteria to treat food allergies – though it is still early days.