Human Cytomegalovirus Compromises Development of Cerebral Organoids

Area of Science:

• Neurovirology
• Developmental Neuroscience
• Stem Cell Biology

Background:

• Congenital human cytomegalovirus (HCMV) infection is a major cause of central nervous system (CNS) birth defects, including microcephaly and hearing loss.
• Understanding HCMV's effects on neural cells is crucial for developing effective interventions.
• Previous studies highlight abnormalities in developing cortical tissue from infected clinical samples.

Purpose of the Study:

• To investigate HCMV-host interactions in neural progenitor cells and their derivatives.
• To model HCMV-induced CNS birth defects using a three-dimensional cerebral organoid system.
• To compare pathologies observed in organoids with those in clinical HCMV infection samples.

Main Methods:

• Infection of induced pluripotent stem cell (iPSC) lines with HCMV.
• Differentiation of infected iPSCs into three-dimensional cerebral organoids.
• Detection of viral antigens (HCMV IE1 protein) and analysis of neural marker expression (β-tubulin III) and tissue architecture.

Main Results:

• HCMV-infected iPSCs were susceptible but not permissive to infection; viral antigens expressed upon differentiation.
• Infected cerebral organoids showed necrosis, large vacuoles/cysts, and altered cortical structure organization and lamination.
• Significant decrease in cortical structure sites and aberrant β-tubulin III expression were observed, mirroring clinical findings.

Conclusions:

• HCMV infection dramatically alters neurological development in cerebral organoids, recapitulating key features of congenital HCMV disease.
• The 3D cerebral organoid system provides a tractable model for studying HCMV pathogenesis and host-virus interactions in the developing brain.
• This model system facilitates future investigations into HCMV-induced birth defects and potential therapeutic strategies.