Ts-Biotag, a multimodal reporter of Tie2 expression, labels microglia in a model of neuro injury

Abstract

The Ts-Biotag transgenic mouse reports the expression of receptor tyrosine kinase Tie2, a known marker of angiogenic states for both vascular endothelial cells and macrophages. We demonstrate Ts-Biotag labeling and Tie2 expression in a neural injury model to find the majority of labeling occurs in the myeloid derived and brain resident cell type, microglia. Additionally the ligand of Tie2, Ang1, is dynamically expressed, first in astrocytes then neural progenitor during wound signaling and healing. These results offer a Tie2 specific, in vivo view of a neuroimmune response to injury, suggesting a microglia/neural progenitor intercellular interaction guides recovery from a brain lesion.