Abstract
Human brain tissue models such as cerebral organoids are essential tools for developmental and biomedical research. Current methods to generate cerebral organoids often utilize Matrigel as an external scaffold to provide structure and biologically relevant signals. Matrigel however is a nonspecific hydrogel of mouse tumor origin and does not represent the complexity of the brain protein environment. In this study, we investigated the application of a decellularized adult porcine brain extracellular matrix (B-ECM) which could be processed into a hydrogel (B-ECM hydrogel) to be used as a scaffold for human embryonic stem cell (hESC)-derived brain organoids. We decellularized pig brains with a novel detergent- and enzyme-based method and analyzed the biomaterial properties, including protein composition and content, DNA content, mechanical characteristics, surface structure, and antigen presence. Then, we compared the growth of human brain organoid models with the B-ECM hydrogel or Matrigel controls in vitro. We found that the native brain source material was successfully decellularized with little remaining DNA content, while Mass Spectrometry (MS) showed the loss of several brain-specific proteins, while mainly different collagen types remained in the B-ECM. Rheological results revealed stable hydrogel formation, starting from B-ECM hydrogel concentrations of 5 mg/mL. hESCs cultured in B-ECM hydrogels showed gene expression and differentiation outcomes similar to those grown in Matrigel. These results indicate that B-ECM hydrogels can be used as an alternative scaffold for human cerebral organoid formation, and may be further optimized for improved organoid growth by further improving protein retention other than collagen after decellularization.
Highlights
The development of brain organoids for studies on neurodevelopment and disease has emerged as a novel research field [1]
A hydrogel prepared at a concentration of 15 mg/mL with lyophilized brain extracellular matrix (B-extracellular matrix (ECM)) would contain a total amount of 1.70 mg/mL collagen
We showed that porcine B-ECM hydrogels could be produced from native adult porcine brain, with few host cells remaining
Summary
The development of brain organoids for studies on neurodevelopment and disease has emerged as a novel research field [1]. The differentiation and maturation of neuronal tissue within brain organoids is induced by adding differentiation factors to the culture medium. During this process, aggregated cells organize into a 3D spherical structure, with a partly brain-like architecture with ventricular zones as well as deep- and upper-layer neurons [2]. Besides these cortical structures, more specific brain regions can be developed in the organoids, such as the midbrain and hypothalamus [4, 6, 7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
