Taras Kreslavskiy

How did you first become interested in science?

I think I became interested in science quite early, during school. In Russia, there is a system of extracurricular education centres for children, where you could join different activities for free — science, sports, all kinds of things. When I was in seventh grade, I signed up for several clubs, from cosmonautics to fencing. The one I stayed with was biology.

During the winter we had lectures every week, and in the summer, we went on expeditions to collect biological samples. In my case, I worked mostly with freshwater invertebrates. Later, we analysed them during the school year. That was really how I got into biology. I found that work really interesting.

When I started studying at St. Petersburg State University, I initially thought I might go into invertebrate zoology, or something related to that. But then I discovered immunology and became fascinated by the fact that immune cells rearrange their DNA to build antigen receptors that can recognise pathogens. I found that incredibly exciting, and from then on I focused on immunology.

After Russia, you moved to Germany and later to the United States. How did that path unfold?

During my undergraduate and master’s studies, I spent some time in Berlin, which was my first longer experience abroad. Later I moved to Boston to do my PhD at Harvard University. After the defence I stayed in my PhD lab for a short postdoc to finish up some projects.

During my PhD, I worked on T cells and was mostly applying to T cell labs in Europe for my next step. Sometime before that, Meinrad Busslinger came to Boston to give a seminar. I really enjoyed the talk — It was a mechanistic study of B cell development, a field in which Meinrad has been a leading figure for decades. Later, my PhD supervisor, Harald von Boehmer, forwarded me an ad for a postdoc position in Meinrad’s lab. Although I was mostly applying to T cell labs, at the time Meinrad was looking for postdocs for projects involving both B cells and T cells, so I applied. The first time I really learned about the IMP was when I came to Vienna for the interview.

What were your first impressions of the IMP and the Vienna BioCenter campus?

It was very impressive. But I think you only fully appreciate the place once you actually start working there.

The facilities and infrastructure are incredible. I always joke that I was spoiled twice in my life: first by my grandmothers when I was a child, and then by the IMP facilities.

Everything worked smoothly, and there was a huge amount of support. Of course, later you realise that most research environments are not quite like that. When you move elsewhere, it can come as a bit of a shock.

What stood out to you most about life on campus?

What made the Vienna BioCenter special was not only the science, but also the atmosphere. There were many activities that helped create a real community — social hours, dragon boating, skiing trips. For someone moving to a new country, that social environment mattered a lot because you immediately met people and built friendships.

I also liked that these activities included non-scientific staff. I think that creates a sense of shared purpose. People supporting the research understand the scientists and the work they are enabling, and scientists interact with everyone else on campus more naturally.

You spent around six years at the IMP. What were you working on during that time?

I joined the IMP in 2013. My main project became the study of a very unusual subset of B cells called B1 cells, which develop early in life and later self-renew. We identified an interesting transcription factor involved in regulating these cells and followed up on it using knockout mouse models.

That work later opened several new directions for my own lab. Some of the projects we still pursue today actually originated from observations we made during my time at the IMP.

How did the transition from postdoc to group leader feel?

It was a bit of a cold shower. At places like the IMP, new group leaders receive strong institutional support and substantial resources. In many other places in Europe, the situation is very different. Often there is little or no startup package, and sometimes even funding for one’s own salary must be obtained externally.

Scientifically, though, it was extremely exciting. One thing I learned at the IMP was to aim for the most exciting questions that are out there, even if they seem risky – rather than to focus on safer but less interesting projects. That mindset strongly influenced how I built my own research program.

What kind of research does your lab focus on today?

Our lab studies how lymphocytes make cell fate decisions. We are particularly interested in two areas. One focuses on immunological memory — specifically how memory B cells are formed, maintained, and reactivated. These cells are very important because they help the immune system respond to vaccines and to evolving pathogens. This work directly stems from my time at the IMP.

The second direction focuses on innate-like lymphocytes, especially gamma delta T cells. These are fascinating cells because, despite having highly diverse antigen receptors, we still understand surprisingly little about what they recognise or how they function. We are trying to understand the biology and specificity of these cells.

Looking back, what impact did the IMP have on your scientific career?

In my first years at the IMP, I would attend seminars in which I barely understood half of what was being presented, but I was constantly amazed by the creativity and ambition of the science around me.

People across the Vienna BioCenter were working on brain organoids, fly navigation in virtual reality, magnetoreception in birds — all kinds of unusual and exciting questions. Seeing that environment encouraged me to think more broadly and more ambitiously about science.

What do you enjoy most about being a group leader today?

The freedom is the most rewarding part. You can have an idea, discuss it with someone in the lab, and immediately explore it experimentally. You are free to pursue any exciting question.

And because multiple people are working on different projects, there is always something interesting happening. There is always some new result, some unexpected observation, something exciting emerging from the data. Those moments are by far the most rewarding part of the job.