An Allograft Glioma Model Reveals the Dependence of Aquaporin-4 Expression on the Brain Microenvironment
Figure 2
Immunoreactivity against AQP4 (red) and GFAP (green).
(A) In human glioblastoma tissue AQP4 (red) shows an intensive staining whereas in primary cell culture of this glioblastoma AQP4 could not be detected (B). (C) Primary cell culture of astrocytes stained for AQP4. (D) Immunoblot against AQP4; the lower band (32 kDA) represents the AQP4 isoform M23 and the upper band (34 kDA) the isoform M1. Tubulin was used as loading control for these samples (40 kDA). The western blot is positive for AQP4 in the glioblastoma tissue (left lane), whereas the primary glioma cell cultures were negative (middle). Primary mouse astrocytes are positive for AQP4 (right lane). The M23-AQP4 isoform always shows a stronger band than the M1 isoform.