Balthasar A. Heesters, PhD

As a scientist and team leader, I am eager to further human knowledge. I like to solve technical and intellectual problems with creativity and innovation. It is my goal to operate at the edge of knowledge and uncover general principles in biology to disseminate these ideas among my peers and the public.

About me

Welcome to my curriculum vitae! This page is (unlike my lab's website) about me. It will take you through my career and explain how I got interested in immunology, antibodies and sugars.

A little bit about my upbringing. I was born in Amsterdam, but grew up in Zeeland (both in the Netherlands). After more than 10 years in the national sailing team I now enjoy windsurfing and field hockey. Besides sports I get a lot of energy from being a dad.

If you're curious to dive deeper into my work, you can follow me:

Research experience

Assistant Professor (tenured)
Utrecht University
2021 - Present

High affinity antibodies are a hallmark of effective vaccination and can provide long-lasting protection. My lab aims to understand the regulation and mechanism of antigen driven selection of B cells in the germinal center (GC).

Principal Investigator (veni laureate)
Spits lab, Amsterdam University Medical Centers
2017 - 2021

Single cell RNA sequencing of human lymphoid stromal cells, including FDC, revealed a regulation of T and B cells by FDCs. The data generated many hypotheses that still need to be tested. I used R and Python to analyze the data and validated several findings on sorted primary cell cultures.

Visiting Scientist
Carroll lab, Harvard Medical School

To test my hypothesis the Carroll lab developed FDC specific PD-L1 knockout mice.

Postdoctoral Fellow
Spits lab, Amsterdam University Medical Centers
2016 - 2017

We identified Innate Lymphoid Cell precursors in the blood, for this project. I established transcriptomics in the lab, helped with the analysis, design and writing.

Postdoctoral Fellow
Chiu lab, Harvard Medical School
2015 - 2016

Our collaboration on bacteria-sensing nociceptors gave Isaac the opportunity to start his own lab at HMS. He asked me to setup the lab and train new lab members. I made and validated a knockout mouse with CRISPR-Cas9 and investigated the role of pain neurons in immunity against cancer. I left the lab to further my career in the Netherlands.

Visiting Scientist
Walker lab, Ragon Institute
2013 - 2014

I showed that infectious HIV persists in human FDCs in a protected endocytic compartment, which can be purged by a CR2 decoy receptor.

PhD Candidate
Carroll lab, Harvard University
2011 - 2015

I identified a novel mechanism by which FDCs retain antigen for long periods of time. We developed whole lymph node 3D imaging techniques and identified resident DCs as the main drivers for immunity against influenza, contrary to skin draining DCs.

Master Student Immunology
Carroll lab, Harvard University

In 6 months I worked towards a paper identifying resident dendritic cells as the main transporters of S. Pneumoniae to FDCs in the lymph node.

Master Student Virology
de Groot lab, Utrecht University
2008 - 2009

Using the tools available in the lab I identified a novel sialic acid modification in vivo and established imaging of O-acetylated sialic acids on immune cells.


PhD in Immunology
Harvard University, Boston (USA)
Utrecht University, Utrecht (the Netherlands)

2011 - 2015

Master of Science in Infection and Immunity
Utrecht University, Utrecht (the Netherlands)
2008 - 2010

Bachelor of Science in Biomedical Sciences
Utrecht University, Utrecht (the Netherlands)
2005 - 2008

VWO Natuur & Gezondheid
S.S.G. Nehalennia, Middelburg (the Netherlands)
1999 - 2005


Discover the proficiencies that I bring to science.

Scientific Writing

Proficient in crafting scientific documents and effectively communicating complex research findings. Can be a stickler for grammar.

Graphic Design

Skilled in affinity designer (highly recommend), which I use to create impactful visuals for teaching, research and lab presentations.


Experienced R and python to analyze and quantify single cell RNA sequencing, flow cytometry and microscopy data.

State-of-the-Art Techniques

Proficient in flow cytometry and cell sorting, as well as intravital 2-photon microscopy and single cell RNA sequencing.

Collaborative & Creative

I like to help people, which often ends in collaboration.

Hypothesis Driven



Grant Writing

Publication Network

Network analysis shows previous collaborations, independence and mobility. (Meta)analysis of ones own work can give fun insights.This analysis was done in python using networkx.


How the lab is


Active grants:

  • NWO ZonMw VIDI grant

Previous grants:

  • Erasmus Scholarship to Melissa Ripamonti
  • NWO ENW XS grant
  • Polygon innovation fund
  • NWO ZonMw VENI grant
  • WBSO grant
  • NVVI work visit grant
  • AMR postdoc fund
  • Ragon Innovation Award

Let's collaborate!

Ready to do science?