Assessing a food allergy patient's overall diet during immunotherapy trials could unlock understanding how the microbiome affects the allergic reaction.
After outlining the role and beneficial addition of a dietitian on the modern food allergy care team in her interview with MD Magazine® while at the American College of Allergy, Asthma & Immunology (ACAAI) 2019 Scientific Meeting in Houston, Carina Venter, PhD, RD, associate professor of Pediatric Allergy & Immunology at the University of Colorado School of Medicine, discussed how the complex gut microbiome likely influences variety in patient allergy progression and immunotherapy outcomes.
MD Mag: What is the role of gut microbiome in food allergy?
Venter: So, I think what is fact is that the gut microbiome is key in allergy prevention and allergy management. I think the other fact is that we do not know what to manipulate, and we do not know how to manipulate it.
I had literally just been talking to somebody who's looking at how particular strains of microbiota can change epigenetics. So we do know that the gut microbiome is central in modulating whatever is going on in the immune system, and that the gut microbiome produced short chain fatty acids such as butyrate, which regulates or up-regulates T regulatory cells, which sort of just calm down the immune system.
So we know it's key, we know there's a difference in gut microbiome between children with food allergies and without food allergies. We know there's a difference in the gut microbiome between children who remain food allergic and those who develop tolerance. But if you, for example, look at studies from Saudi Arabia versus studies from New York, and you look at cow's milk-allergic children—it was actually a multicenter study from across the United States, although it was the Mount Sinai team who presented the data—it’s very different from the cow's milk allergy kids in Saudi Arabia.
So we just know we’re at the point where you can say, that is the bug, or that is the strain that we need to fix. It's exciting times but we're still trying to decipher exactly what we need to do.
MD Mag: Are cultural diet differences a major influence in food allergy effect?
Venter: If what you're asking is whether we perhaps need to look at dietary patterns when we do OIT: yes, of course. I have just spoken to Brian Vickery and I say to him, ‘Brian if you ever need somebody to monitor what else the patients are eating while you're doing this oral immunotherapy trial, I’m here.’
And I do we could perhaps explain why some people improve on an oral immunotherapy treatment and others don't, because the underlying diet is different. We see a lot of serious adverse reactions when they do milk oral immunotherapy therapy in Japan.
Now it could be genetics, it could be a million other reasons, but it may just be because the underlying diet in Japan is so very different from what we see in Canada, where they do a lot of milk oral immunotherapy, but they don't seem to see the severe reactions that they find in Japan.
So, I definitely think underlying diet, diet patterns, and perhaps the opportunity of the diet to modulate the gut microbiome in particular, is important to study, even in the oral immunotherapy trials.