Increased motor neuron survival in the Aplec strain is associated with more prominent T-cell infiltration. Microarray expressional profiling in Aplec rats suggested involvement of T cells. To confirm this, ipsilateral L3-5 spinal cord segments from DA, PVG and Aplec rats were analyzed with flow cytometry 5 days after VRA. The relative proportion of CD3+ cells was significantly increased in Aplec rats compared to both DA and PVG rats (A-D). A-C show representative flow cytometry plots from one animal in each group. To approximate the absolute number of CD3+ cells in the tissue, the total number of cells acquired/100 seconds was measured in each animal, demonstrating more CD3+ cells in DA rats compared to PVG rats, but there were no significant differences between DA and Aplec rats suggesting a similar absolute number of T cells in the strains, but with a relatively larger proportion of T cells in Aplec rats. Also CD11b+ cells were analyzed, revealing around 50% of the cells in the tissue to be CD11b+ with no strain differences (A-C and F), although there was an insignificant trend for DA rats to have a higher total number of CD11b+ cells (G). Aplec: antigen-presenting lectin-like receptor gene complex; VRA: ventral root avulsion.