Biology subjects

Schomann, T.

Publications and source records attributed to Schomann, T..

3 recordsLinked to original sources

bioRxiv2026

Spatial transcriptomics defines the mechanisms of hiPSC derived stem cell mediated repair in human articular cartilage

We here determined therapeutic efficacy and mode-of-action of human induced pluripotent-derived therapeutic stem cells (hiMSCs) across in vivo mouse and ex vivo human osteoarthritis models. hiMSC treatment in DMM-mice significantly reduced OARSI damage scores, which was affirmed by a decrease in the catabolic marker Mmp13 and an increase in the anabolic marker Col2. These treatment effects appeared, irrespective of modifying factors such as xeno-free media or thermosensitive hydrogel carrier. Subsequently treatment of hiMSC+gel in human osteoarthritic cartilage explants showed a transcriptome-wide significant activation of the cholesterol and sterol synthesis pathways marked by genes such as MVD, DHCR7, MSMO1, FABP3. Additionally, we showed that these changes alleviated OA-associated imbalances of the cellular Zinc-ion homeostasis pathways, represented by genes such as MT1F, MT1G, MT1H and SLC30A1. Spatial transcriptomics then sensitively captured that hiMSC+gel treatment evoked, specifically at the superficial cartilage layer, a consistent upregulation of healthy chondrocyte markers such as CHAD, ACAN, FRZB, and SOX9, alongside a suppression of catabolic and inflammatory mediators such as SERPINE1, SPP1, MMP13, ADAMTS5. Our findings link therapeutic outcomes of hiMSC treatment to precise spatially resolved molecular changes in human tissue, that would otherwise be obscured by heterogeneous cell populations. Collectively our study highlighted that hiPSC-derived stem cell therapy (hiMSCs) could provide a scalable off-the-shelf solution to treat osteoarthritis, with strong prospects for clinical applications in the near future.

developmental biology↗

bioRxiv2025

Advancing Therapeutic Solutions: Poloxamer-based Thermosensitive Injectable Hydrogels containing a Self-assembling Peptide for In situ Gelation in an Osteoarthritis Murine Model

This study presents the development and characterization of a novel thermosensitive injectable hydrogel designed to enhance the biomechanical properties of poloxamer 407 (P407) through the incorporation of a self-assembling peptide. The primary objective was to engineer a formulation that rapidly gels following intra-articular (i.a.) injection, exhibits improved mechanical strength, and enables sustained release of embedded therapeutic cargo. Gelation time assays demonstrated that the P407-peptide formulation solidified more quickly than P407 alone at equivalent concentrations. Rheological analysis revealed a 1.5 kPa increase in storage modulus in the hybrid hydrogel, confirming improved mechanical integrity. In vitro biocompatibility was assessed using human chondrocytes, with MTS assays and LIVE/DEAD staining indicating no cytotoxicity across tested concentrations. To evaluate in vivo applicability, a near-infrared fluorescent (NIRF) dye was incorporated into the hydrogel and injected intra-articularly into an osteoarthritis (OA) mouse model. The labeled formulation allowed for successful tracking and demonstrated localized gelation, supporting its suitability for site-specific, sustained delivery. Overall, the P407-peptide hydrogel offers a promising platform for i.a. therapeutic applications, combining injectability, rapid thermoresponsive gelation, mechanical reinforcement, and controlled release behavior, making it well-suited for regenerative medicine and OA treatment.

biochemistry↗

bioRxiv2023

An EGF-modified PLGA-lanthanide nano platform for combined NIR-II cancer imaging and targeted drug delivery

The use of multifunctional nanoplatforms for synergistic therapy and imaging is a promising approach in cancer treatment. In this study, we exploited the imaging properties of lanthanides by encapsulating CaF2:Y, Nd along with the chemotherapeutic drug doxorubicin (DOX) into poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) to prepare a nanoplatform suitable for imaging in the second near-infrared (NIR-II) window and simultaneous anti-cancer therapy. To facilitate the accumulation of CaF2:Y, Nd+DOX@PLGA NPs in breast cancer cells, we modified the NPs with EGF. The diameter of the obtained CaF2:Y, Nd+DOX@PLGA/PEG/EGF NPs was approximately 150 nm, with a nearly round shape and homogeneous size distribution. In addition, analysis of the drug release behaviour showed that DOX was released more readily and had a longer release time in acidic environments. Accordingly, MTS results indicated that DOX-loaded NPs were significantly cytotoxic. Furthermore, fluorescence microscopy and flow cytometry studies revealed that CaF2:Y, Nd+DOX@PLGA/PEG and CaF2:Y, Nd+DOX@PLGA/PEG/EGF NPs were gradually taken up by 4T1 breast cancer cells over time, and EGF-coated Nd+DOX@PLGA NPs exhibited increased uptake rates after 72 h. Moreover, we found that EGF increased the solubility of Nd+DOX@PLGA NPs in water by comparing the aqueous solutions of the different NPs formulations. Finally, NIR imaging demonstrated strong fluorescence of PLGA NPs carrying CaF2:Y, Nd NPs at 900-1200 nm under 808 nm laser excitation. In conclusion, the developed CaF2:Y, Nd+DOX@PLGA/PEG/EGF NPs could be monitored for an extended period of time, and co-encapsulated DOX could be efficiently released to kill breast cancer cells.

cancer biology↗