STEMdiff Microglia Maturation Kit

This research-use kit from STEMCELL Technologies forms part of the STEMdiff™ microglia culture system, which combines a Differentiation Kit and the Maturation Kit to differentiate and mature microglia derived from human pluripotent stem cells (hPSCs) following upstream generation of hematopoietic progenitor cells with the STEMdiff™ Hematopoietic Kit. The resulting cells are described as a highly pure population of microglia, characterized as greater than 80% CD45/CD11b-positive and greater than 50% TREM2-positive, with less than 20% morphologically distinct monocytes or macrophages, and are intended as versatile tools for modeling human neurological development and disease, drug screening, toxicity testing, and cell therapy validation.

The kit contains STEMdiff™ Microglia Basal Medium along with Supplements 1, 2, and 3. The Basal Medium is stored at 2 - 8°C, while the supplements are stored at -20°C, and all components are stable for 2 years from the date of manufacture indicated on the label. For maturation, cultureware may be coated with Corning® Matrigel®, or for immunocytochemistry applications with poly-D-lysine (PDL) or fibronectin. In the workflow, cells previously cultured for 24 days in differentiation medium are replated at 1 x 10^5 cells/cm^2 in STEMdiff™ Microglia Maturation Medium and incubated at 37°C and 5% CO2. Microglia are considered mature after 4 - 10 days in this medium, after which they have limited capacity for expansion and may show increased cell death beyond 10 days of culture.

The Maturation Kit is also referenced in a co-culture protocol for combining hPSC-derived microglia with forebrain neurons under optimized conditions, targeting a final density of 5% microglia. Materials required but not included with the kit include DMEM/F-12 with 15 mM HEPES, conical tubes, Trypan Blue, and Corning® Matrigel®.