UCSF

The ventricular-subventricular zone (V-SVZ) has long been a region of great interest due to the invaluable role that it plays in generating neurons throughout development. Studies in rodents have shown that the quantity and identity of neurons born within the V-SVZ change not only temporally but spatially, with different regions of the mouse V-SVZ giving rise to distinct neuronal subtypes. In the human brain, however, certain regions of the V-SVZ have expanded to accommodate a need for greater cell numbers, including the addition of an outer sub-ventricular zone and the presence of the Arc, a three-tiered structure present during the perinatal period of development that is located at the dorsal horn of the lateral ventricle. Given the novelty of these findings, it remains unclear how these expansions change the local cytoarchitecture of different parts of the V-SVZ and how these changes may affect the local proliferating cell population. To explore these questions, we use the piglet brain as a proxy for the human brain due to its similar developmental trajectory during the perinatal period of development. Using histological and imaging techniques, we identified both spatial and temporal differences in cellular architecture and composition between four sub-regions of the V-SVZ. We additionally discovered significant differences in both the density and distribution of proliferative cells between different sub-regions. Finally, we provide evidence that proliferating cell populations in different sub-regions have distinct identities. These findings suggest that different regions of the V-SVZ in large-gyrified brains may act as distinct niches, giving rise to different neuronal and glial populations.