Astrocytes derived from fetal neural progenitor cells as a novel source for therapeutic adenosine delivery

PCR and Western Blot. (A) PCR: results of isolated cells from Adk^+/−×Adk^+/− matings. Based on these results, an Adk^−/− clone needed for the experiment could be detected. The genomic DNA was amplified using the three allele-specific primers o107, o108 and o109. DNA from Adk^+/− cells gives a combination of the wild-type specific 640bp band (primers o107/o108) and the knockout-specific 840bp band (primers o107/o109), while DNA from Adk^−/− cells gives rise to only a 840bp band (primers o107/o109), demonstrating the bi-allelic genetic disruption of the Adk locus. (B) Western Blot: above the GAPDH immune reactivity for protein control is shown (38kDa). Beneath ADK immune reactivity is shown (44–46kDa). A clear reactivity is found in wild-type cells, whereas no reactivity is found in non-differentiated and differentiated Adk^−/− cells (CO=control wild-type; KO 1d=Adk^−/− after 24h; KO 1w=Adk^−/− after 1 week).

Expression of neural stem cell markers. Left: Immunostaining with nestin (red) and GFAP (green) in Adk^−/− cells (A) and wild-type cells (C). Scale bar=100μm. Right: Immunostaining with Sox2 (red) in Adk^−/− cells (B) and wild-type cells (D). Scale bar=50μm. Nuclei are stained with DAPI (blue).

Glial and neural differentiation of neural progenitor cells in vitro. Left: Immunostaining with GFAP (red) in Adk^−/− cells (A) and wild-type cells (C). Right: Immunostaining with tau (red) in Adk^−/− cells (B) and wild-type cells (D). Nuclei are stained with DAPI (blue). Scale bar=100μm.

Adenosine releases from Adk^−/− cells (blue) and corresponding wild-type cells (red) in 24h. (A) Adenosine released from 100,000 non-differentiated cells: adenosine release from Adk^−/− cells is significantly higher compared to wild-type cells. (B) Adenosine released from 100,000 differentiated cells: adenosine release from Adk^−/− cells is significantly higher compared to wild-type cells. Standard errors are marked with black bars. Significance is marked with an asterisk (*): p<0.05.