Isala, the sequel: longer & more than just vaginal microbiome

In recent months, with the help of a robot and six job students, we have extracted all the microbial DNA from the vaginal swabs of more than 3300 women, you, our so precious Isala participants. Then — after what we can only call a marathon lab work session – we read out the pieces of genetic code of the bacteria with a ‘sequencing’ device. For example, with the help of bioinformatics, we have used these codes to identify bacteria and discover the microbial composition of your vagina! Thanks to the extensive questionnaire you have completed, we can link that data to information about your health, lifestyle, eating habits, partners, etc. Also, plenty of new lactobacilli and other good bacteria are grown from the other swab (pink), which means that our biobank now almost contains 2000 novel isolates.

There was one important aspect that we hadn’t considered yet: the dynamics of the vaginal microbiome.

Enter phase 2

We all know that our hormones go up and down throughout our menstrual cycle and that we don’t eat equally healthy or do sports every day. Therefore, in phase 2 of Isala, we asked 275 women to provide six vaginal samples over two menstrual cycles. We selected these women as diversely as possible, based on a complex scientific algorithm by our biostatisticians and a lot of consultations with other scientists. Using different swabs on these two cycles, we want to learn even more about the influence of contraception, hormones, diet and personal hygiene on the vaginal microbiome.

For example, we think that estrogen and progesterone have an important influence on vaginal lactobacilli. But we’re not sure. Because these hormones are in contraceptives in all kinds of variants, we therefore chose women with different contraceptive use. Your partner’s microbiome can also play an important role. And then, there is the influence of dietary patterns (see our previous blog post). For example, we want to know whether eating a lot of fiber and complex carbohydrates, which are generally good food sources for the bacteria in our intestines, also influence the vaginal lactobacilli. And vice versa, whether fast sugars can actually aggravate a fungal infection. We also examine the microbiome of the saliva to see if we find effects of our food, hormones or lifestyle in it.

We even hope to collect data for a breakthrough in forensics. That is why we ask all women in this phase 2 to donate a saliva sample and three skin samples (around the mouth, chest and groin). For example, we can use these vaginal, skin and saliva samples as a reference in some studies of sexual assault.

More than enough enthusiasm, limited budget

Why we would only allow 275 women to participate for phase 2 and not everyone who wanted to? (because you were so excited, again, a big thank you!), is purely for budget reasons. We mentioned earlier that microbiome research is costly, which means that we have to make choices all the time. And because we will use a slightly more high-tech analysis (shotgun sequencing) in phase 2, one sample costs more than 150 euros, without personnel costs. Hopefully, we can include more great Isala participants in the future.