Zebrafish Model Identifies New Drugs for Kaposiform Lymphangiomatosis (KLA)

Please introduce yourself

Hi, my name is Ivan Bassi. I worked in Weizmann in the lab of Prof. Karina Yaniv for six years as a postdoc. During this time, I conducted 2 projects. One was related to blood-brain barrier, and the second one, in collaboration with IDEA Bio-Medical, we studied the lymphatic disease called Kaposiform Lymphangiomatosis (KLA).

It is a severe disease that affects children and there are no currently treatment for this disease. So using zebrafish as a model, our small fish, we managed to mimic the human features and physiology of this disease.

We were able to identify some new drugs using the Hermes high content imaging system, that are efficient in treating this disease and can reverse the phenotype in the fish.

How does the work with Hermes system compare to other microscopes?

I used to work a lot with confocal microscopes. The advantage of Hermes system is that it’s really fast, and the quality of the images is good.

So for our purpose, that was to perform high throughput screening, because we needed to test a lot of drugs to identify the good ones in a relatively small amount of time, it worked perfectly. Hermes system was perfectly fitting the aim of our project.

What can you tell us about Hermes system’s throughput?

We needed to image the fish very fast because the fish can die and we couldn’t run the project for too long. So the fact that it can acquire an entire plate in 20 minutes, it was amazing for us. Hermes system is very fast in acquiring the images.

I think that for a 96 well plate with 96 Zebrafish inside, it took something like 15 minutes, 20 minutes to take pictures of the entire fish in the plate.

We ran about two, three plates with drugs for each experiment. So is took us usually one week to analyze and generate the data and the graphs that we needed for the project.

Let’s say we ran two or three plates per week, this allowed us to test the big amount of drugs that in the end we tested during the project in a few months.

How was your experience using Athena software for zebrafish analysis?

Before using the Athena software, I was using a lot of free software available on the internet to perform analysis, but it was always very long, tedious and complicated and required a lot of passage.

While when I started to use the Athena, it was really easy and user-friendly, and it was very fast also to have the results for the analysis that we wanted to do for this project.

This allowed us to screen more than 130 drugs in very few months and to have good results and identify the drugs that were more efficient in treating the Kaposiform Lymphangiomatosis (KLA)disease.

How was your experience with getting support from IDEA Bio-Medical?

Luckily, we were in contact with Jason Otherstrom, who I think is the product specialist of IDEA Bio-medical. He was always available via Zoom. We had met, especially at the beginning of the project, we had many meetings to try to understand which of the features of the fish were more representative for the phenotype and for us to understand if the drug was working or not, and also to better set the flow of the experiment, for instance how we need to prepare the fish, how many fish and the alignment of this fish in the plate to get the best results from the Hermes microscope.

How long did it take you to become independent using Hermes system & Athena software?

It was relatively fast, thanks also to the fact that we got a lot of support from Jason. He was always available to help us and to explain us all. We talked a lot with him, presenting our problems and our needs and which type of calculation we wanted to do, and he helped us a lot. So it was really, really fast because the software is very user-friendly.

Tell us about the new paper you published based on data generated by Hermes & Athena 

The Preprint is titled “A high-throughput zebrafish screen identifies novel candidate treatments for Kaposiform Lymphangiomatosis (KLA)” and is available in bioRxive,

We are now in the last stage of the revision, and I hope that this will be soon out.

We were treating a very aggressive disease in humans that is called Kaposiform Lymphangiomatosis (KLA), and currently there are no treatments for this disease. And the patients, they don’t respond to the normal treatment.This is an infiltrative disease that leads to enlargement of lymphatic vessels and the lymphatic system is not working anymore.

What we did was to identify, first we identified in children a new mutation for one of the genes that is involved in this disease.

We took this gene and we overexpressed the human gene in the zebrafish. Thus, we generated a system that allowed us to induce the mutation whenever we want and in the tissue that we want. In this case, the tissue was lymphatic tissue.

After this, we characterized this model and we discovered that the fish was presenting the same defects as humans, making it a good model to proceed and to try to test and identify new drugs.

After this first stage, what we did was to take a library of 130 drugs that are associated with lymphatic diseases, or with a pathway of this gene, and test them to identify some useful drugs in fish that was able to rescue the fish’s phenotype.

Eventually we identified 3 drugs. These 3 drugs were then taken and tested with human cells to see if what we saw in fish was conserved also in humans. And we found 2 new drugs that are effective also on human cells.

These are primary cells, directly from the patient, and the drugs proved useful to revert their phenotype.

We hope that with this work, we bring a new possible therapy for this severe disease, Kaposiform Lymphangiomatos (KLA).

What is the impact of this study?

It proves that zebrafish present very conservative features, not only anatomically but also in terms of pathways, with humans.  This means that they can be a good model system to screen drugs.

I think that in the future, we will try to mimic human disease in fish even more and to test drugs.

I believe that what we did now and with this paper Is really important, not only in the context of this lymphatic disease, but also to prove once more that the zebrafish has not only anatomical features that are conserved with humans, but also pathways, and it can help in drug screening.

It will serve as sort of a pipeline, a system, and we can apply this to other diseases and we can use zebrafish to mimic human disease and get some preliminary drug screening, which of course will need to be validated in the future in mammals, like mouse and also in human cells. But it will give us a boost to reduce time and to have fast results.

reference: A high-throughput zebrafish screen identifies novel candidate treatments for Kaposiform Lymphangiomatosis (KLA). Bassi, I., Jabali, A., Farag, N., Egozi, S., Moshe, N., Leichner, G.S., Geva, P., Levin, L., Barzilai, A., Avivi, C. and Long, J., 2024. bioRxiv, pp.2024-03. doi: https://doi.org/10.1101/2024.03.21.586124