Stemgent® Alkaline Phosphatase Staining Kit II

The Stemgent® Alkaline Phosphatase (AP) Staining Kit II detects alkaline phosphatase activity, a phenotypic marker of pluripotent stem cells.

Embryonic stem (ES) cells are stem cells derived from the inner cell mass of the blastocyst stage embryo, are pluripotent and capable of long-term self-renewal. ES cells are able to differentiate into all derivatives of the three primary germ layers: ectoderm, endoderm, and mesoderm; ES cells can be differentiated in vitro to a diverse range of progenitor and terminally differentiated cell types. Undifferentiated embryonic stem (ES), embryonic germ (EG) and embryonal carcinoma (EC) cells exhibit elevated expression of alkaline phosphatase (AP). The state of differentiation can be monitored by detection of AP along with stem cell markers such as transcription factors Oct-3/4, Nanog, Sox-2 and surface markers SSEA-1, -3, -4, TRA-1-60 and TRA-1-81. Although stem cells from different sources or species display different cell surface markers (see Table 1), AP is a universal marker for all types of pluripotent stem cells.

Alkaline phosphatase (AP) is a hydrolase enzyme responsible for dephosphorylating molecules such as nucleotides, proteins, and alkaloids under alkaline conditions. There are various methods of detecting AP such as those based on enzymatic reaction followed by colorimetric or fast red violet dye, and others based on fluorescent detection and immunostaining. The Stemgent® Alkaline Phosphatase Staining Kit II is a histochemical assay for use on cells grown in tissue culture wells or dishes. It uses a solution containing napthol AS-BI phosphate as substrate and fast red violet dye as the colorimetric read-out for the enzymatic activity. The AP-positive, undifferentiated cells stain red. For added convenience, the activated substrate can be used up to 30 minutes after mixing. The stain develops quickly, does not readily fade, and can be analyzed from 15 to 30 minutes after application to the sample.

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