Reliable High-Throughput Genotoxicity Skin Assay

AMSBIO announces the launch of DermaChip® - a new high throughput assay technology that allows scientists, for the first time, to reliably measure the genotoxic risk of a whole range of environmental agents (including cleaning agents, household products and industrial chemicals as well as cosmetics) to our skin.

Using risk assessment data from a micronucleus assay together with the traditional Comet analysis of cells isolated from treated 3D skin culture models has been shown to be a better predictor of skin toxicity compared to the standard battery of in vitro toxicity assays. However, in some in vitro models, unacceptable backgrounds are observed as a function of skin preparation. 

DermaChip® combines extracellular matrix 3D Culture technology with CometChip® technology** to provide a unique platform able to specifically isolate basal keratinocytes for genetic toxicology testing using in vitro skin models. The elimination of cells migrating to the stratum corneum, that potentially harbour damaged DNA from the analysis, reduces the background for some 3D models.

DermaChip® technology is based on the incorporation of collagen I into our CometChips®, forming a disposable gel attached to the specially treated 96-well format glass slides. Instead of being randomly dispersed in agarose on a glass slide as in the traditional Comet Assay, cells in the DermaChip® are captured on an array of microwells. Each well contains approximately 400 microwells of 30 microns diameter, displayed in a defined pattern and depth which causes the captured test cells to reside in a single plane. Leveraging this advance - a single 96-well DermaChip® can produce 20,000 data points per chip, based on an average of 208 cells imaged per well.

The collagen gel specifically traps basal keratinocytes expressing integrin beta-1 before they differentiate and migrate to the stratum corneum. During their natural migration, cells stop dividing and ultimately lose their nucleus. During the process, DNA damage accumulates resulting in high comet backgrounds. By trapping basal keratinocytes, DermaChip® eliminates this background. Prior to Comet analysis, the identity of trapped cells is confirmed by Anti-integrin beta-1 immunostaining labeled with quantum dots. Only basal keratinocytes are included in comet data analysis.

** The Single Cell Gel Electrophoresis assay, also known as Comet assay, is a sensitive technique for the detection of DNA damage at the level of the individual eukaryotic cell. The 96-Well CometChip® System is a high-throughput platform proven to simultaneously treat and measure DNA damage induced by different treatments, or among different cell types on a single slide using the Comet assay.