Immortalized Mouse Microglia (SIM-A9)

Microglia cells are resident macrophages of the brain and spinal cord and they act as the first and the main form of active immune defense in the nervous system. In addition to expressing microglial specific markers CD68 and Iba1, the spontaneously Immortalized Mouse Microglia (SIM-A9) retains responsiveness to exogenous inflammatory stimulation (LPS and β-amyloid) and the ability to secret cytokines and nitric oxide as well as phagocytose biological debris. Upon LPS and IL-4 stimulation, these cells are capable of switching between the pro-inflammatory microglial phenotype, M1, which is associated with elevated iNOS and COX-2 followed by IкB and tyrosine kinase pathways and the regenerative-supportive phenotype, M2, which is identified by an increased in Arg-1 expression, respectively. SIM-A9 exhibits key attributes of primary microglia and is useful in characterization of stimulus-triggered microglial migration, proliferation and phagocytosis.

Immortalization Method: Spontaneous immortalization

BioSafety Level: II

Species: Mouse

Source Organ: Postnatal mouse cerebral cortices

Growth Properties: Adherent

Morphology: Round or Polygonal

Population Doubling: 30 - 40 hours

Seeding Density: 45,000 - 50,000 cells/cm²; Recommended split ratio is 1:2

Markers: CD68, Iba1

Donor Age: N/A

Donor Gender: N/A

Donor Ethnicity: N/A

Propagation: The base medium for this cell line is Prigrow IV medium available at abm (TM004). To make the complete growth medium, add the following components to the base medium: heat-inactivated fetal bovine serum to a final concentration of 10% donor horse serum (Thermo Fisher Scientific; Cat. no. 1605013) to a final concentratio of 5% and Penicillin/Streptomycin Solution (G255) to a final concentration of 1%.

Stimulation of microglia can be done by adding 2.5 ng/ml LPS, or 20 µM β-amyloid fibrils (Aβ_1-42).
Carbon dioxide (CO₂): 5%, Temperature: +37.0°C.

Quality Control: 1) Functional assays such as the nitrate assay was performed to assess nitric oxide production; 2) ELISA was used to determine the TNFα secretion after inflammatory stimulation; 3) Western blot and immunocytochemistry were used to confirm the expression of microglial specific markers such as CD68 and Iba1 and M1/M2 phenotype-associated protein expression (COX-2/iNOS and Arg-1) after stimulation; 4) Aβ_1-42 or E. coli-derived bioparticles uptake was used to determine phagocytic activity of SIM-A9 cells.

Shipping Condition: Dry Ice

Storage Condition: liquid nitrogen or -180°C