Figure 9. Genetic Tract Labeling.

In vivo gene delivery vectors with dual promoters can identify specific neurons in vivo that express a candidate regeneration gene of interest, and can label the axonal projections of these neurons exclusively. In this case, AAV2 vectors expressing a candidate regeneration gene and the copGFP gene have been injected into the rat motor cortex. The axonal projections of these neurons in the spinal cord exhibit copGFP labeling (Low et al., 2010). (A) Corticospinal axons expressing copGFP are labeled with a light-level antibody as they approach a C3 dorsal column lesion site; bone marrow stromal cells have been grafted (g) into the lesion. (B) In a different field, individual axons that have incorporated the copGFP reporter are shown with fine morphological detail.