Bio: Dr. Leopold Koenig is a senior scientist and project manager at TissUse GmbH, a leading company in the field of Organ-on-a-Chip technology. He specializes in developing alternatives to animal testing, tissue engineering, and in vitro substance safety assessment. Dr. Koenig earned his master’s degree in biotechnology from TU Berlin in 2016, following studies at TU Berlin and Dongseo University in Busan. In 2022, he completed his Ph.D. at TU Berlin, where he modeled the neurovascular niche in microphysiological Multi-Organ-Chip systems. Since 2017, Dr. Koenig has been actively managing contract R&D projects for pharmaceutical and biotech clients, advancing the development of cutting-edge microphysiological systems. His expertise encompasses iPSC cultivation and differentiation, multi-organ co-cultivations – focusing on stem cell-derived neurovascular and liver models–and primary human bone marrow models for preclinical safety and efficacy testing. A regular presenter at international conferences, including the MPS World Summit and the World Congress on Alternatives and Animal Use in the Life Sciences, Dr. Koenig is dedicated to showcasing innovations in Organ-on-a-Chip technology and its applications for advancing human-relevant research.

Abstract: The increasing prevalence of immune system diseases among children highlights the vulnerability of the developing immune system to toxicants. Immunotoxic effects can manifest in primary lymphoid organs, such as the bone marrow, and secondary lymphoid organs, like the lymph node. Animal models often have poor translational relevance to humans due to species-specific differences in immune cell development, signaling pathways, and responses to immunomodulatory compounds. We present a human in vitro bone marrow model and a lymph node model in our HUMIMIC chip platform. The bone marrow model consists of CD34+ hematopoietic stem cells and mesenchymal stromal cells in a zirconium oxide scaffold. This microfluidic system supports differentiation into monocytes, granulocytes, and NK cells over 31 days, with lineage balance and cytokine release disrupted by pro-inflammatory factors. Incorporating T cells enables the study of adaptive immune responses, including T cell activation and target cell killing. The lymph node can be modeled using monocyte-derived dendritic cells and autologous lymphocytes embedded in a collagen hydrogel. This system responds to model antigens with robust cytokine release, T cell activation, and IFN-γ secretion, effectively replicating adaptive immunity. Together, these models offer advanced platforms to investigate the immune-modulatory effects of compounds in vitro.