Related Experiment Video
Updated: Jan 17, 2026
Isolation and Flow Cytometric Assessment of Neuroimmune Interactions in a Mini-Stroke Murine Model
Published on: June 20, 2025
Multicolor fate mapping of microglia reveals polyclonal proliferation, heterogeneity, and cell-cell interactions
Majed Kikhia1,2,3, Simone Schilling1,2,4,5, Marie-Louise Herzog1,2,5
1Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Charitéplatz 1, 10117, Berlin, Germany.
Abstract:
Microglial proliferation is a principal element of the inflammatory response to brain ischemia. However, the precise proliferation dynamics, phenotype acquisition, and functional consequences of newly emerging microglia are not yet understood. Using multicolor fate mapping and computational methods, we here demonstrate that microglia exhibit polyclonal proliferation in the ischemic lesion of female mice. The peak number of clones occurs at 14 days, while the largest clones are observed at 4 weeks post-stroke. Whole-cell patch-clamp recordings of microglia reveal a homogeneous acute response to ischemia with a pattern of outward and inward currents that evolves over time. In the resolution phase, 8 weeks post-stroke, microglial cells within one clone share similar membrane properties, while neighboring microglia from different clones display more heterogeneous electrophysiological profiles. Super-resolution microscopy and live-cell imaging unmask various forms of cell-cell interactions between microglial cells from different clones. Overall, this study demonstrates the polyclonal proliferation of microglia after cerebral ischemia and suggests that clonality contributes to their functional heterogeneity. Thus, targeting clones with specific functional phenotypes may have potential for future therapeutic modulation of microglia after stroke.
Insights
Microglia undergo polyclonal proliferation after brain ischemia, leading to functional diversity. Understanding these microglial clones could offer new therapeutic strategies for stroke recovery.
Area of Science:
- Neuroscience
- Immunology
- Cell Biology
Background:
- Microglial proliferation is key in brain ischemia's inflammatory response.
- The dynamics and function of new microglia post-ischemia remain unclear.
Purpose of the Study:
- To investigate microglial proliferation dynamics and functional heterogeneity after cerebral ischemia.
- To understand the electrophysiological properties and cell-cell interactions of clonal microglial populations.
Main Methods:
- Multicolor fate mapping and computational analysis in female mice.
- Whole-cell patch-clamp recordings to assess microglial electrophysiology.
- Super-resolution microscopy and live-cell imaging for cell interactions.
Main Results:
- Demonstrated polyclonal microglial proliferation in the ischemic lesion.
- Identified peak clone numbers at 14 days and largest clones at 4 weeks post-stroke.
- Observed homogeneous acute microglial response, evolving into heterogeneous electrophysiological profiles in later stages, with distinct clonal interactions.
Conclusions:
- Microglial clonality contributes to functional heterogeneity after cerebral ischemia.
- Targeting specific microglial clones may offer novel therapeutic approaches for stroke modulation.
