FlowCellect™ Human ESC (TRA-1-60) Surface Marker Characterization Kit; 25 Tests

Human embryonic stem cells (hESCs) are unique cells in that they can be maintained in vitro as pluripotent cells and can be induced to differentiate into many cell types by manipulating culture conditions. Therefore, hESCs have the potential of providing an unlimited supply of cells for cell-based therapy as well as providing a resource to study basic human developmental biology. Subsequently, much attention has focused on directing hESC differentiation along specific developmental lineages [1-4].

Currently, the most utilized method to test for the undifferentiated state of hESCs is to analyze the expression of the proteins OCT4, NANOG, Alkaline phosphatase, SSEA3, SSEA4, TRA-1-60, and TRA-1-81 [5]. Antibodies for TRA-1-60 and TRA-1-81 both recognize a keratan sulfate associated antigen but differ by epitope specificity (6). The stage specific embryonic antigens or SSEAs (SSEA1, 3 and 4) have also been used as a marker of undifferentiated hESCs (7). The antibodies for SSEAs recognize epitopes on related glycosphingolipids or GSLs(8). The SSEA4 antibody recognizes the terminal sialic acid on GSL-7 (8). Both TRA-1-60 and SSEA4 are both expressed on human embryonal carcinomas and on human embryonic stem cells (9). Upon differentiation, TRA-1-60 and SSEA4 expression levels decrease and SSEA1 expression increases on human embryonic stem cells over time when treated with Retinoic acid (10).

The FlowCellect™ Human Embryonic Stem Cell Surface Marker Characterization kit uses an antibody-based detection method, utilizing fluorescently conjugated antibodies to detect TRA-1-60, SSEA4 and SSEA1. The FlowCellect™ Human Embryonic Stem Cell Surface Marker Expression kit is designed for specifically for flow cytometers with a single blue (488 nm) laser light source. The FlowCellect™ Human Embryonic Stem Cell Surface Characterization kit is not intended for use in microscopy applications including ICC, IHC and HTS, western blot or any other fluorometric analysis platforms.

The kit is optimized for use on the Guava EasyCyte™ Plus cytometer that requires cell concentrations to be less than 500 cells per microliter. The kit does not include culture media and materials or other materials that should be readily available in a common laboratory setting that routinely performs experiments of the type described here.