Neuronal PirB Upregulated in Cerebral Ischemia Acts as an Attractive Theranostic Target for Ischemic Stroke

BackgroundIschemic stroke is a complex disease with multiple etiologies and clinical manifestations. Paired immunoglobulin‐like receptor B (PirB), which is originally thought to function exclusively in the immune system, is now also known to be expressed by neurons. A growing number of studies indicate that PirB can inhibit neurite outgrowth and restrict neuronal plasticity. The aim of the study is to investigate whether PirB can be an attractive theranostic target for ischemic stroke. Methods and ResultsFirst, we investigated the spatial‐temporal expression of PirB in multiple ischemic stroke models, including transient middle cerebral artery occlusion, photothrombotic cerebral cortex ischemia, and the neuronal oxygen glucose deprivation model. Then, anti‐PirB immunoliposome nanoprobe was developed by thin‐film hydration method and investigated its specific targeting in vitro and in vivo. Finally, soluble PirB ectodomain (sPirB) protein delivered by polyethylene glycol–modified nanoliposome was used as a...