Related Experiment Video
Updated: Jul 30, 2025
A 3D Spheroid Model for Glioblastoma
Published on: April 9, 2020
Functional Analysis of a Novel Immortalized Murine Microglia Cell Line in 3D Spheroid Model
Gabrielle Angst1, Xin Tang1, Chenran Wang2
1Department of Cancer Biology, University of Cincinnati College Medicine, Cincinnati, OH, 45267, USA.
Abstract:
Microglia are the residential immune cells of central nervous system and they are crucial for brain development and homeostasis, as well as the progression of inflammatory brain diseases. To study microglia's physiological and pathological functions, one of the most widely used models is primary microglia culture from neonatal rodents. However, primary microglia culture is time consuming and needs a great number of animals. In our microglia culture, we found a strain of spontaneously immortalized microglia that continued to divide without any known genetic intervention. We confirmed the immortalization of these cells for uninterrupted thirty passages and we named them as immortalized microglia like-1 cells (iMG-1). The iMG-1 cells kept their microglia morphology, and they expressed macrophage/microglia-specific proteins of CD11b, CD68, P2RY12, and IBA1 in vitro. iMG-1 cells were responsive to inflammatory stimulations with lipopolysaccharide (LPS) and Polyinosinic:polycytidylic acid (pIpC), triggering increased mRNA/protein levels of IL1-β, IL-6, TNF-α, and interferons. LPS and pIpC treated iMG-1 cells also significantly increased their accumulation of lipid droplets (LDs). We also generated a 3D spheroid model using immortalized neural progenitor cells and iMG-1 cells with defined percentages to study neuroinflammation. The iMG-1 cells distributed evenly in spheroids, and they regulated the basal mRNA levels of cytokines of neural progenitors in 3D spheroid. iMG-1 cells were responsive to LPS by increased expression of IL-6 and IL1-β in spheroids. Together, this study indicated the reliability of iMG-1 which could be readily available to study the physiological and pathological functions of microglia.
Insights
Researchers discovered spontaneously immortalized microglia-like-1 (iMG-1) cells, offering a reliable model for studying brain immune cell functions without extensive animal use or time investment.
Area of Science:
- Neuroscience
- Immunology
- Cell Biology
Background:
- Microglia are vital immune cells in the central nervous system, crucial for brain health and disease.
- Current primary microglia cultures are time-consuming and require numerous animals.
- A need exists for more efficient and accessible microglia models.
Purpose of the Study:
- To establish and characterize a novel, spontaneously immortalized microglia cell line.
- To validate the utility of this cell line for studying microglial physiology and neuroinflammation.
Main Methods:
- Isolation and culture of primary microglia from neonatal rodents.
- Confirmation of cell immortalization through passage number and characterization of cell markers (CD11b, CD68, P2RY12, IBA1).
- Stimulation assays with lipopolysaccharide (LPS) and Polyinosinic:polycytidylic acid (pIpC) to assess inflammatory responses.
- Generation of 3D spheroid models with immortalized neural progenitor cells and iMG-1 cells.
Main Results:
- A spontaneously immortalized microglia cell line, iMG-1, was established and maintained for over thirty passages.
- iMG-1 cells retained microglia morphology and expressed key microglial markers.
- iMG-1 cells demonstrated robust inflammatory responses to LPS and pIpC, with increased cytokine production and lipid droplet accumulation.
- In 3D spheroids, iMG-1 cells influenced neural progenitor cytokine levels and responded to LPS stimulation.
Conclusions:
- The immortalized microglia-like-1 (iMG-1) cell line provides a reliable, accessible, and efficient model for investigating microglial functions.
- iMG-1 cells can be utilized in various experimental settings, including 2D cultures and 3D neuroinflammation models.
- This cell line reduces the reliance on primary cultures and animal usage, accelerating microglia research.
