ALDH1L1-immunoreactivity gradually increased within intermediate zone, subplate, and cortical plate with stage (Kharlamova et al., 2024).
At the turn of the early to middle fetal period (20–21 GW), all transitional zones of the developing cortex demonstrated GFAP-immunoreactivity of different expressiveness: the most densely packed immunoreactive cell zones are and surrounding inner SVZ. Two
subzones of more abundant GFAP-immunoreactive cells and fibers were described within IZ. IZ contained two subzones of rich GFAP-immunoreactivity lay in a arc in medial-dorsal and dorsal-lateral hemisphaeria walls. This GFAP-immunoreactive pattern characterized all giving material of the middle gestational age (Kharlamova et al., 2024).
The distribution of NeuN immunoreactive cells was similar to the previous stages. In parietooccipital sulcus, NeuN-immunopositive cells were distributed throughout the cortical plate, in calcarine sulcus – only in the deeper layers of the cortical plate (Godovalova et al., 2024).