Fig. 2.

Transduction of neurons and glial cells of the mouse brain by lentiviral vectors-qualitative comparison. Micrographs a, c, e, g, i, and l have been taken from location 2 marked in Fig. 3, micrographs b, d, f, h, k, and m from location 1. Note that EGFP expression (green staining) was always stronger in glial cells (arrowheads) than in neurons (arrows), but that proportion of transduced neurons and glial cells differed according to the vector that was injected into the brain. Vectors with the accessory proteins Vpx or Vpr seemed to evoke increased EGFP expression and thus higher intensity of the fluorescence signal compared to the same vector without this protein. In the PBjSEW vector, the Vpx protein additionally changed the preferred infection site from neurons to glial cells (compare a and b vs. c and d). Double fluorescence immunohistochemistry, EGFP = green, NeuN (neuronal marker) = red, overlay = yellow; thickness of the optical section = 2 µm; co = cortex, cc = corpus callosum, scalebar 50 µm