FIGURE 2.

Astrocyte-derived human TG2 has no significant effect on myelination in spinal cord cultures. (A,B) Wild-type human TG2 (hTG2) and empty vector were lentivirally expressed in astrocytes (LV TG2 and MOCK, respectively) which were used as an astrocyte feeding layer in myelinating spinal cord cultures. Myelination was measured as percentage of myelinated axons, visualized with myelin basic protein (MBP, myelin marker, green) of total neurofilament (NF, red)-positive axons at 26–28 days in vitro. Representative images are shown in A. The relative percentage of myelinated axons in spinal cord cultures with hTG2-expressing astrocytes to MOCK treated astrocytes is shown in B (n = 3). (C) Spinal cord cultures on a control astrocyte feeding layer were treated with vehicle (PBS) or with recombinant guinea pig TG2 (gpTG2, 50 μg/ml every 2 days from day 12 in vitro for 14–16 days). Representative images are shown in C. The relative percentage of myelinated axons in gpTG2 treated spinal cord cultures compared to vehicle-treated (CTRL) cultures is shown in D (n = 4). Data are shown as mean + SEM, calculated as average percentage compared to MOCK-transduced (B) or vehicle-treated astrocytes (D, CTRL), which were set to 100% in each independent experiment. Statistical analyses were performed using a one-sample t-test (not significant). Scale bar is 100 μm.