ABSTRACT
Why individuals with Down syndrome (DS) are more susceptible to SARS-CoV-2-induced neuropathology remains elusive. Choroid plexus (ChP) plays critical roles in barrier function and immune response modulation and expresses the ACE2 receptor and the chromosome 21-encoded TMPRSS2 protease, suggesting its substantial role in establishing SARS-CoV-2 infection in the brain. To explore this, we established brain organoids from DS and isogenic euploid iPSC that consist of a core of functional cortical neurons surrounded by a functional ChP-like epithelium (ChPCOs). DS-ChPCOs recapitulated abnormal DS cortical development and revealed defects in ciliogenesis and epithelial cell polarity in ChP-like epithelium. We then demonstrated that the ChP-like epithelium facilitates infection and replication of SARS-CoV-2 in cortical neurons and that this is increased in DS. Inhibiting TMPRSS2 and furin activity reduced viral replication in DS-ChPCOs to euploid levels. This model enables dissection of the role of ChP in neurotropic virus infection and euploid forebrain development and permits screening of therapeutics for SARS-CoV-2-induced neuropathogenesis.
Subject(s)
Brain , COVID-19 , Choroid Plexus , Down Syndrome , Organoids , SARS-CoV-2 , Serine Endopeptidases , Choroid Plexus/virology , Choroid Plexus/metabolism , Choroid Plexus/pathology , Organoids/virology , Organoids/metabolism , Organoids/pathology , Humans , SARS-CoV-2/physiology , COVID-19/virology , COVID-19/pathology , COVID-19/metabolism , Serine Endopeptidases/metabolism , Serine Endopeptidases/genetics , Down Syndrome/metabolism , Down Syndrome/pathology , Down Syndrome/genetics , Brain/virology , Brain/pathology , Brain/metabolism , Neurons/metabolism , Neurons/virology , Neurons/pathology , Virus Replication , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/virology , Furin/metabolism , Furin/genetics , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Viral TropismABSTRACT
In response to the scarcity of advanced in vitro models dedicated to human CNS white matter research, we present a protocol to generate neuroectoderm-derived embedding-free human brain organoids enriched with oligodendrocytes. We describe steps for neuroectoderm differentiation, development of neural spheroids, and their transferal to Matrigel. We then detail procedures for the development, maturation, and application of oligodendrocyte-enriched brain organoids. The presence of myelin-producing cells makes these organoids useful for studying human white matter diseases, such as leukodystrophy.
