Human-Mouse Chimeric Brain Models to Study Human Glial-Neuronal and Macroglial-Microglial Interactions.

Area of Science:

• Neuroscience
• Stem Cell Biology
• Developmental Biology

Background:

• Human-mouse chimeric brain models using induced pluripotent stem cells (hiPSCs) are vital for in vivo study of human neural cells.
• Understanding glial-neuronal interactions is critical for brain function and neurological disorder treatment.

Purpose of the Study:

• To investigate human glial-neuronal interactions in vivo.
• To create a human-mouse chimeric brain model with human microglia, macroglia, and neurons.

Main Methods:

• Co-transplantation of hiPSC-derived neural progenitor cells and macrophage progenitors into neonatal mouse brains.
• Super-resolution imaging, 3D reconstruction, and single-cell RNA sequencing.
• Cell-cell communication analysis.

Main Results:

• Human microglia were observed pruning synapses and engulfing human neurons.
• Single-cell RNA sequencing confirmed recapitulation of human glial progenitor populations and astroglial development.
• Identified key interactions: neurexin-neuroligin (neuronal-astroglial), SPP1 (microglial-astroglial), and PTN-MK pathways (macroglial progenitors).

Conclusions:

• The co-transplantation model effectively generates human neural cells within the mouse brain, enabling study of their interactions.
• This model provides insights into glial-neuronal communication, synapse formation, and cellular dynamics relevant to neurological diseases.
• Highlights the potential for studying non-cell-autonomous effects in human neurological disorders.