Trem2 Knockout RAW 264.7 Cell Line

The Trem2 Knockout RAW 264.7 Cell Line is a CRISPR/Cas9-edited murine macrophage cell line that features targeted disruption of Trem2, a key innate immune receptor. By creating a loss-of-function model, it enables rigorous investigation of TREM2-dependent signaling networks and their functional outcomes in phagocytosis, cell survival, and inflammatory regulation. This well-characterized knockout line provides a reliable tool for mechanistic studies and drug screening applications in the context of macrophage biology.

The host line, RAW 264.7, is an Abelson leukemia virus-transformed macrophage cell line derived from BALB/c mice. These cells retain hallmark monocyte/macrophage characteristics, including robust responsiveness to inflammatory stimuli such as lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-??), and active phagocytic capacity towards microbial targets and apoptotic debris. Their immortalized yet functionally competent nature allows for reproducible and scalable experiments, making them a staple model for innate immunity research.

TREM2 is a transmembrane immune receptor that recognizes phospholipids, apolipoprotein E (ApoE), and ApoJ. Ligand binding triggers association with the adaptor DAP12 (TYROBP), which recruits and activates Syk kinase. Syk then phosphorylates downstream effectors to stimulate PI3K/AKT and MAPK/ERK cascades, leading to activation of transcription factors NF-??B and AP-1. This pathway drives expression of phagocytic receptors such as MerTK, promotes cell survival through Bcl-2 family proteins, and modulates lipid metabolism genes including Lpl and Abca1. Upstream regulators of TREM2 include the lineage transcription factor PU.1, inflammatory cytokines (TNF-??, IL-1??), and microbial products like LPS, ensuring integration of diverse environmental cues.

Disruption of TREM2 in the RAW 264.7 macrophage background abrogates DAP12/Syk-mediated signaling, resulting in impaired phagocytic clearance of pathogens and debris, altered production of cytokines such as TNF-?? and IL-6, and dysregulated lipid handling. These functional deficits closely mirror macrophage dysfunction observed in TREM2-associated neurodegenerative diseases, including Alzheimer??s disease and Nasu-Hakola disease, as well as in rheumatoid arthritis. Consequently, this knockout cell line serves as a pathophysiologically relevant model for dissecting TREM2-dependent mechanisms in neuroinflammation and for evaluating therapeutic strategies targeting the TREM2 pathway.

The cell line supports a broad range of experimental approaches. Phagocytosis can be quantified using pHrodo-labeled E. coli or myelin debris; TREM2 protein and mRNA levels validated by Western blotting, flow cytometry, and RT-qPCR; cytokine secretion measured via ELISA; and downstream signaling assessed by phospho-specific antibodies against Syk. Lipid uptake assays and apoptosis analysis extend functional characterization, while RNA sequencing captures global transcriptomic changes. The model is also compatible with high-throughput compound screens for TREM2 agonists or antagonists. For further information regarding this product, please contact Ascent Research.