PhD Scientific Days 2024

Poster Session E - Molecular Medicine 2.

Characterization and modification of chondroitin sulfate proteoglycans to enhance transplantation efficiency of enteric neural stem cells in an experimental Hirschsprung's disease model

Text of the abstract

Introduction: The enteric nervous system (ENS) is a complex network of neurons and glia that controls gut motility. During embryogenesis, the ENS is generated by neural crest-derived multipotent stem cells that enter the foregut, migrate caudally, and differentiate into enteric ganglia. In the mesenchymal environment of the gut tube, cell migration is regulated by a combination of growth factors, permissive (fibronectin, laminin), and non-permissive (chondroitin sulfate proteoglycans) extracellular matrix molecules (ECM). Abnormal enteric neural crest-derived cell (ENCDC) migration lead to neurocristopathies, such as Hirschsprung's disease, that result in the absence of enteric ganglia at variable lengths in the distal colorectum. Transplantation of in vitro cultured enteric neural stem cells (ENSCs) into Hirschsprung animal models shows low integration efficiency, cell migration and proliferation, which is insufficient to restore intestinal functionality.
Aims: We aim to characterize microenvironmental factors that enhance the transplantation efficiency of ENSCs, focusing on detailed characterization and experimental modification of non-permissive ECM molecules.
Methods and results: Detailed immunohistochemical characterization of embryonic day (E)5-E10 chicken hindgut, shows the dynamic expression pattern of chondroitin sulfate proteoglycans within the gut mesenchyme. In vitro cultures of E5 hindgut in the presence of chondroitinase ABC (chABC), results in the disorganization of concentrically migrating ENCDCs within the gut wall. Transplantation of PBS-soaked microbeads or enteric neurospheres into the hindgut dissected from E18 embryos results in the accumulation of CSPG immunoreactivity and limited cell migration around the transplantation site. Cells cultured in the presence of 1U/ml chABC show enhanced migration capacity upon transplantation into the gut wall.
Conclusion: We hypothesize that increased CSPG expression has inhibitory effects on the integration, migration, and survival of ENSCs in the intestinal wall. Modulating the expression of ECMs in the postnatal intestinal environment can enhance the success of stem cell replacement therapies for neurointestinal diseases.

Funding: OTKA-K-138664, Semmelweis 250+ Scholarship for PhD Excellence