Dr. Julia Esser-von Bieren

The fascination of scavenger cells

Dr. Julia Esser-von Bieren is heading the new "Innate Immunomodulation" Young Investigators Group at the Center of Allergy and Environment (ZAUM), a joint undertaking of the Helmholtz Zentrum München and the Technische Universität München. She is investigating how macrophages are permanently activated and trigger inflammatory processes.

Dr. Julia Esser-von Bieren, Source: Helmholtz Zentrum München

Macrophages are immune cells that control acute inflammatory responses. However permanent activation of these cells can lead to chronic inflammation. "Our research has shown that macrophages play a crucial role in type 2 immune responses in allergies and parasitic infections," Julia Esser-von Bieren explains. She is heading Helmholtz’s new "Innate Immunomodulation" Young Investigators Group at the Helmholtz Zentrum München and the Technische Universität München. "However it is not clear how macrophages become permanently reprogrammed in such a way that they contribute to chronic type 2 inflammation." In addition, there is a lack of approaches for reversing the pathological reprogramming of macrophages.

Which factors control macrophages?

Now Esser-von Bieren explores previously unknown mechanisms, which she analyzes by state of the art metabolome, transcriptome and epigenome analyses. She also wants to know how the immune system can be reprogrammed in a way that will allow the macrophages to fulfill their normal role again. "This should allow our work to contribute to the development of new therapeutic approaches," she states.

"I am fascinated by the versatility and plasticity, meaning the changeability, of macrophages," Esser-von Bieren continues. These cells perform a wide range of tasks, both in allergies and during host defence against worms (termed "type 2 immune responses"). In these settings, macrophages respond promptly to signals from the environment and adjust their metabolism and mediator output accordingly. "Many aspects of this reprogramming are very poorly understood, particularly in allergies," the researcher knows.

There are also major differences between macrophages in humans and those in mice, although "immunological research often focuses solely on the mouse". Esser-von Bieren explains, "It is important to me to take the patient as the starting point of my research and then decipher the mechanisms in the model, and not the other way around."

Additional funding

In order to answer these questions, Esser-von Bieren is collaborating with a number of groups. Now the Deutsche Forschungsgemeinschaft (DFG) is also funding the FOR2599 "Tissue type 2 immunity" research unit with 2.4 million euros for the next three years. Together with Caspar Ohnmacht (also IAF), Esser-von Bieren will be leading the subproject “Macrophage-intrinsic regulators of type 2 inflammation”. Prof. Axel Roers, Director of the Carl Gustav Carus Medical School Institute for Immunology at TU Dresden, is the coordinator of the research unit. Together the scientists are investigating the desirable effects of type 2 immune responses, such as wound healing and the metabolic balance. However, these responses also cause allergies and promote tumor growth.

The Zentrum scores with translational aspects

It is not by accident that Esser-von Bieren's path took her to the Helmholtz Zentrum München. "As a postdoc, I somewhat missed the translational aspect that I had greatly appreciated during my doctoral work at the Karolinska Institute," the Young Investigators Group leader reports. "Therefore I was looking for a center that could offer me the opportunity to conduct translational research in the field of allergies and immunology." In addition, working with patients at a university clinic, which is possible at the ZAUM, was particularly important to her. She was also persuaded by the scientific environment in Munich.

"Valuable member of the team"

"Thanks to the excellent degree programs at the Munich universities and Munich's appeal, it is very easy to find good doctoral students and postdocs who are motivated and well trained," Esser-von Bieren explains. Supervising the young scientists is very close to her heart. "It is especially important to me to structure the individual supervision in such a way that they can all use their strengths and appreciate themselves as valuable members of the team." She sees it as her mission to support doctoral students in taking the professional path that suits them best. "This is unfortunately often neglected in academic research," Esser-von Bieren knows.

Further information

* With the Helmholtz Young Investigators Group program, the Helmholtz Association offers internationally outstanding postdocs the opportunity to build up their own research groups. Applications are taken for up to 20 Young Investigators Groups each year in January. The projects are then awarded in a highly competitive selection process and funded for six years with a total of at least 1.8 million euros.

Key publications

Dietz K, de los Reyes Jiménez M, Gollwitzer ES, Chaker A, Zissler UM, Rådmark OP, Baarsma HA, Königshoff M , Schmidt-Weber CB, Marsland BJ, Esser-von Bieren J , Age dictates a steroid resistant cascade of Wnt5a, transglutaminase-2 and leukotrienes in inflamed airways, J Allergy Clin Immunol. 2017, Apr;139(4):1343-1354.e6.

Esser-von Bieren J, Volpe B, Sutherland DB, Bürgi J, Verbeek JS, Marsland BJ, Urban JF, Harris NL. Immune antibodies and helminth products drive CXCR2-dependent macrophage-myofibroblast crosstalk to promote intestinal repair. PLoS Pathog. 2015, Mar;11(3):e1004778.

Esser-von Bieren J, Mosconi I, Guiet R, Piersgilli A, Volpe B, Chen F, Gause WC, Seitz A, Verbeek JS, Harris NL. Antibodies Trap Tissue Migrating Helminth Larvae and Prevent Tissue Damage by Driving IL-4Rα-Independent Alternative Differentiation of Macrophages. PLoS Pathog. 2013 Nov; 9(11): e1003771.

Esser J, Gehrmann U, D'Alexandri FL, Hidalgo-Estévez AM, Wheelock CE, Scheynius A, Gabrielsson S, Rådmark O. Exosomes from human macrophages and dendritic cells contain enzymes for leukotriene biosynthesis and promote granulocyte migration. J Allergy Clin Immunol. 2010 Nov; 126(5):1032-40, 1040.e1-4.

Website:
Helmholtz Young Investigators Group "Innate Immunomodulation"