Evaluation of M2-like macrophage enrichment after diffuse traumatic brain injury through transient interleukin-4 expression from engineered mesenchymal stromal cells

We report the effects of acute M2-like macrophage enrichment in a mouse closed head injury model of diffuse traumatic brain injury. Enrichment is achieved by engineering mesenchymal stromal cells with synthetic interleukin-4 (IL-4) mRNA to transiently express IL-4. Through a transcriptomic analysis of treated brain tissue, we begin to understand the effects of acute IL-4 and M2-like macrophage enrichment. Left brain cortex from naïve mice (SHAM) and mice with closed head injury and left hemisphere treatment with either phosphate-buffered saline (PBS), naïve mesenchymal stromal cells (MSC), or interleukin-4 expressing MSCs (IL-4 MSC)