Microbiome and Allergic Disease Development

In this episode, Kirsten Kloepfer, MD, speaks about her team’s review titled “The Role of Microbiome in Allergic Disease Development,” including the link between microbiota and immune development and ways to prevent allergic disease development in early life. 

Additional Resource:

• Aguilera AC, Dagher IA, Kloepfer KM. Role of the microbiome in allergic disease development. Curr Allergy Asthma Rep. 2020;20(9):44. doi:10.1007/s11882-020-00944-2

Kirsten Kloepfer, MD, is an associate professor of pediatrics at Indiana University School of Medicine (Indianapolis, Indiana).

TRANSCRIPTION:

Jessica Bard: Hello everyone, and welcome to another installment of Podcast360, your go-to resource for medical news, and clinical updates. I'm your moderator, Jessica Bard with Consultant360 Specialty Network.

Asthma and allergies are 2 of the most common chronic diseases in children, according to the Asthma and Allergy Foundation of America. Dr Kirsten Kloepfer is here to speak with us today about her team's review, the role of the microbiome in allergic disease development. Dr Kloepfer is an associate professor of pediatrics at Indiana University School of Medicine in Indianapolis, Indiana. Thank you for joining us today, Dr Kloepfer. Can you please provide a summary of your team's review?

Dr Kirsten Kloepfer: We wrote this review almost 2 years ago, really at the start of the pandemic. And what we wanted to look to see really what the current literature was showing, and what other people were finding about the microbiome with allergic diseases, because this is an area of interest for me.
So, we do know that bacteria are present, and that's something that we've really started to fill focus in on, and kind of discovered with newer techniques for detecting bacteria within the last 10, 15 years. And so, we do know that it's present in our airway, it's on our skin, it's in our GI tract. And so, my group here, and a lot of other groups across the nation are looking to see how this influences the development of allergy and asthma, and even the persistence of those diseases.

And so, we really wanted to look through the literature and kind of come with a good review for people looking at what we found in food allergy, what we found with eczema, what we found with asthma, and then allergic rhinitis. And so, we worked on this, and we were trying to look at it somewhat clinically as well to help people the translation of this from bench to the clinic to see are there any things we can do clinically to see if there are ways to intervene yet with what's been found kind of at the bench with the microbiome data.

Jessica Bard: You elaborate for us a little bit more on how this review came about? You mentioned some of it there, but really why is it just so important to study?

Dr Kirsten Kloepfer: We're seeing an increase in allergic diseases, in food allergy, in asthma, so I think that this has become a focus for a lot of us that do research in this area is we've come up with some pretty good treatments, although we're continually looking for better treatments for these diseases, but how do we prevent them? And so, we really have found that we're really shifting to trying to look at prevention, which means we're looking at early life. And that is kind of where this is coming from, is our focus on prevention, and seeing if we could prevent children from having asthma long-term. And really start to decrease this increased rate of allergies and asthma that we're seeing.

Jessica Bard: And how does this review impact clinical practice specifically as it leads to allergies and asthma?

Dr Kirsten Kloepfer: Yeah, so clinically, I can't make great recommendations. I wish I could. We think there are some modified exposures, both during the prenatal period and even postnatally. There are a lot of association studies that have been done. We know that kids who are born on farms, there are great studies looking at kids who are born on farms, have a significantly lower rate of allergic diseases. And we know it's from exposure to environmental bacteria and it starts prenatally with mom. So, the infant's immune system is already being primed prenatally. We do know that, but then you can't make a recommendation that everybody has a farm, because that's not practical.

We do know that if you're born into a home where there was a dog with mom when she's pregnant, there seems to be a lower rate of allergic diseases. Again, probably because of bacterial exposure with the animal going in and out of the house bringing microbes in from the outdoors into the house. But, again, you can't really tell everyone to get a pet. We do know, again, the way they're delivered, whether they come out as a vaginal delivery, or C-section 'there's definitely a difference in the infants microbiome based off of how they're born. And so, I know there are studies ongoing trying to figure out if there's a way to address that because there are people that definitely need a C-section.

Same thing with breastfeeding and formula feeding. We know breastfeeding is protective, and we really already knew that, but now we're starting to link it with the microbiome. But that's not always an option. So then, do we try to make formula so that it actually mimics breast milk even more and looking at some of the bacteria involved with that. And then, antibiotic use, we do know that we probably need to use antibiotics judiciously prenatally, and after the baby is born, because that has been linked, and shown that you definitely alter the microbiome when you start antibiotics on an infant. Again, you still have to use them some, but really thinking it through and deciding if they're needed or not.

And then, eating a really healthy diet that's high in fiber, because it's been linked with a microbiome. It's not all put together with a neat bow yet. And then, encouraging breastfeeding, trying not to use too many antibiotics. And then, I think that we're really trying to even go back and look prenatally is where a lot of studies are starting to go, or are headed, and then really trying to get down molecularly, and figure out why we're seeing some of these associations in these children.

Jessica Bard: Well, you mentioned some things on where studies are headed,. But could you elaborate for us a little bit more on what's next for research on this topic?

Dr Kirsten Kloepfer: So, there's a lot of research going on in this area. So, kind of one of the hot topics that everybody hears nowadays. There are several studies going on recruiting mothers prenatally to start following long-term. I think one of our big gaps that have been identified, and that are trying to be addressed is so far a lot of the studies that have been microbiome based have been in high-risk Caucasians, or white children. And so, we're really missing the minority demographic and also across the world because we do see some differences based off of country too, with the bacteria. So, also trying to determine what would be best for children in the United States may not be the same as children in Europe.

We have a study, and another group has a study where we're looking more at inner city. We think that if you grew up in a food desert that actually makes a difference as well, which would address diet in mom and the infant. There are a lot of gaps in our knowledge right now that we're trying to address. And we're looking at PFTs, as well here in Indiana to see if there's a link between what's going on in their microbiome, in their early immune development, and to their airway development.

Jessica Bard: What would you say are the overall take-home messages from our conversation today?

Dr Kirsten Kloepfer: Overall take home is clinically, we still don't have really good recommendations that are coming from the microbiome. Still, really promoting healthy lifestyles, which we all try to do in clinic. And that we're doing our best to try to answer some questions, and really translate what we're finding at the bench, and translate it to clinical use. And for us to be able to counsel our patients, and help try to prevent them from developing asthma, and allergies, or for their children to develop them.

Jessica Bard: Is there anything else that you'd like to add today?

Dr Kirsten Kloepfer: No, I would just thank you for the invitation to speak today.

Jessica Bard: Thank you. Thanks for joining us on the podcast.

Dr Kirsten Kloepfer: Thank you.