Figure 7.

Long-term depletion of microglia after SCI significantly reduces expression of genes related to inflammation and apoptosis in the spinal cord. (A) Venn diagram demonstrates the separation of total injury genes (i.e., those genes differentially expressed in SCI/Veh vs. Sham/Veh - Injury Comparison 2) into those modified by PLX (PLX-Modified) or not modified by PLX (PLX-Unmodified) based on membership in the gene list of PLX Comparison 3 (SCI/Veh vs. SCI/PLX). 57% of total injury genes (218 of 384) were PLX-modified, and all of these genes except one (217 of 218) had an attenuation of the original injury effect. The remaining 43% of injury genes (166 out of 384) were not modified by PLX. (B) Graph illustrating the percent distribution of total injury genes by pathway annotation (and theme) that are PLX-Modified or PLX-Unmodified. The top 6 pathways with the greatest proportion of PLX-modification were all within the theme of Immunity and Inflammation. (C) Heatmap of genes related to cytokine signaling that are differentially expressed (DE) by injury and PLX-Unmodified (left) or PLX-Modified (right). Color coding was based on z-score scaling. (D) Heatmap of genes related to apoptosis that are DE by injury and PLX-Unmodified (left) or PLX-Modified (right). Color coding was based on z-score scaling. The majority of caspases have increased gene expression with injury that is decreased with PLX with the exception of Casp3. Expression for the pro-apoptotic mitochondrial permeabilizing protein, Bax, is increased with injury and decreased with PLX treatment while PLX treatment does not affect expression of the associated anti-apoptotic gene, Bcl2.