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Neuss, S.

Publications and source records attributed to Neuss, S..

2 recordsLinked to original sources

The impact of crystallographic plane orientation as an unexplored terrain in hemocompatible material design

Thrombogenicity causes significant complications in the application of blood-contacting implants, requiring strategies to prevent adverse coagulation reactions. The thrombotic responses to the foreign surfaces are mainly driven by surficial factors such as surface energy, topography, and electrochemical interactions. Although anticoagulation therapies reduce the risks of clotting, patients might still encounter bleeding complications. Therefore, rather than high-risk anticoagulation therapies to counteract coagulation, it is essential to ensure hemocompatibility through the materials intrinsic properties. Endothelialization is crucial in preventing thrombotic complications, with various strategies explored for facilitating endothelial cell adhesion and proliferation. We investigated the impact of crystallographic anisotropy on endothelial and blood cell interactions on four main planes (A-, C-, M-, and R-planes) of single crystalline alumina (-Al2O3, sapphire). Employing advanced surface characterization techniques, including SIMS, KPFM and Zeta potential measurements, our study sheds light on the hemocompatibility of biomaterials considering anisotropic effects. We elucidated that the A-plane of alumina promotes endothelialization and suppresses platelet activation in contrast to other crystallographic planes. Our investigation into cell-surface interactions provides valuable insights and contributes to the advanced biomaterial design, ultimately leading to enhanced clinical outcomes.

bioengineering↗

Non-canonical HIF-1 stabilization is essential for intestinal tumorigenesis

The hypoxia-inducible transcription factor HIF-1 is appreciated as a promising target for cancer therapy. However, conditional deletion of HIF-1 and HIF-1 target genes in cells of the tumor microenvironment can result in accelerated tumor growth, calling for a detailed characterization of the cellular context to fully comprehend HIF-1s role in tumorigenesis. We dissected cell type-specific functions of HIF-1 for intestinal tumorigenesis by lineage-restricted deletion of the Hif1a locus. Intestinal epithelial cell-specific Hif1a loss reduced activation of wnt/{beta}-catenin, tumor-specific metabolism and inflammation, significantly inhibiting tumor growth. Deletion of Hif1a in myeloid cells reduced the expression of fibroblast-activating factors in tumor-associated macrophages resulting in decreased abundance of tumor-associated fibroblasts and robustly reduced tumor formation. Interestingly, hypoxia was detectable only sparsely and without spatial association with nuclear HIF-1 in intestinal adenomas, pointing towards a functional importance of hypoxia-independent, i.e. non-canonical HIF-1 stabilization that has not been previously appreciated. This adds a further layer of complexity to the regulation of HIF-1 and suggests that hypoxia and HIF-1 stabilization can be uncoupled in cancer. Collectively, our data show that HIF-1 is a pivotal pro-tumorigenic factor for intestinal tumor formation, controlling key oncogenic programs in both the epithelial tumor compartment and the tumor microenvironment.

cancer biology↗