MDI Biological Laboratory
President, Professor, MDI Biological Laboratory; Professor, Director, Department of Nephrology and Hypertension, Hannover Medical School

Hermann Haller, M.D.

How can we stimulate blood vessel growth in stem cell derived tissues?

The Haller Lab uses stem cells to grow new renal tissue (renal organoids) and make new kidneys. To understand the process of vascularization and to generate new blood vessels and blood flow within kidney tissue is an important first step in achieving their goal of growing replacement kidneys. 

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Dr. Haller also uses zebrafish embryos to analyze the molecular mechanisms how embryonic kidneys become connected to the aorta and whole body circulation. The Haller Lab is generating transgenic “marker” fish, which allow them to study the cellular movements in the embryonic fish and analyze how the circulation and the embryonic tissue interact and eventually make blood flow in the kidneys possible.  To test their observations, they generate zebrafish deficient (or overproducing) of the factors responsible for vascularization.

Lastly, they use this information in a three-dimensional microcirculatory chamber to stimulate their stem-cell derived organoids to become vascularized. Once blood flow has been established, their organoids can grow and become small kidneys.  In addition, the three-dimensional microcirculatory chambers can also be used to study the “plumbing” of embryonic tubules to a waste system – thereby generating a cellular system to grow kidneys from adult stem cells.

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  • M.D., Free University of Berlin
  • Yale University School of Medicine

Lab Members

Lynne StaggsLab Manager

Pat Schroder, Ph.D.Research Assistant

Cory Johnson, Ph.D.Postdoctoral Researcher

Anastasia Paulmann, M.D.Postdoctoral Researcher