Table 1

Summary of the neurosphere-generating potential of astrocyte monolayers derived from different CNS regions at different ages

NS+NS−
E18 cortexX
E18 cerebellumX
E18 SEZX
P1 spinal cordX
P1 cortexX
P2 cortexX
(5) P2 SEZX
P3 cortexX
P3 cerebellumX
P7 cortexX
P7 spinal cordX
(2) P10 cortexXX
(2) P10 cerebellumXX
(2) P10 spinal cordX
(2) P10 SEZX
P11 cortexX
P11 cerebellumX
P11 spinal cordX
(2) P15 cortexX
(2) P15 SEZX
P16 cortexX
P16 SEZX
(2) Adult cortexX
(2) Adult SEZX
  • A variety of embryonic and postnatal ages were randomly chosen as sources for astrocyte monolayers (n = 36). These monolayers were subsequently tested for the ability to generate multipotent neurospheres, and the temporal arrangement of the results reveals striking differences in neurosphere-generating potential. Astrocytes from all regions are neurosphere-generating (NS+) until around postnatal day (P) 10 or 11 (notice that one set of P10 cerebral cortex and cerebellum cultures were NS+, whereas a different set failed to generate neurospheres (NS−). After this apparent “critical period,” astrocytes derived from the cerebral cortex, cerebellum, and spinal cord are NS−, whereas astrocytes from the SEZ do not observe this critical period and retain the ability to generate neurospheres well into adulthood. One astrocyte monolayer was generated from each age and region, unless indicated otherwise by the number in parentheses.