PSEN2 and Alzheimer disease: While C5ar1 expression is dominant in activated microglia and peripheral myeloid cells, CellChat analysis of hippocampal snRNA-Seq data revealed that inhibition of C5a-C5aR1 signaling affected several intercellular pathways associated with not only microglia, but also astrocytes and oligodendrocytes, consistent with a complex cellular phase of AD initiated by C5aR1-induced secreted mediators67, that may be blunted by this targeted approach in multiple subtypes of AD4,5.