FAQ: 24-Well Chemotaxis Assays

 

Q: Can the inserts be reused?

 

A: Our 24-well migration assays contain 12 individual, removable inserts made out of polycarbonate.  Any unused inserts can be stored at 4ºC until needed, however the inserts should not be used more than once. 

 

Q: Can the inserts be stored after staining migratory cells?

A: The stained inserts can be kept at room temperature for as long as necessary.  When ready to continue, the extraction and reading can be performed.  The insert can be re-stained and air dried before the extraction if planning on taking images after storing the insert.

 

Q: Is it possible to count the cells under microscope?

A: After staining, the cells are visible using a standard inverted microscope.  We usually count 5 randomly selected areas per insert under 10x lens and use the average to report the results.   

 

Q: Can the cells be counted once they are in the Cell Detachment solution?

A: The cells are not able to be manually counted in the detachment solution because there are so few migratory cells and the hemocytometer is not sensitive enough to detect them.  With migration assays, only 5-10% of cells are expected to migrate for even the most aggressive cell line.  If you use the maximum amount of cells in the assay, 100,000 cells, and 10% were to migrate, you would still only have 10,000 cells per assay in 0.4ml.  To use the hemocytometer, there should be greater than 10,000 cells/ml.  The CyQuant dye is much more sensitive and can detect as few as 500 cells.

 

Q: Is the Cell Detachment solution harmful to cells?

A: The Cell Detachment solution is non-enzymatic and is not harmful to the cells. This allows for the option to recover and re-culture the cells following the migration step. The cell detachment solution typically works within 10-20 minutes depending on the cell line but will not damage cells if left in the solution for an extended time period. 

 

Q: Can cells be recovered from this assay?

  

A: The Cell Detachment solution allows for the cells to be recovered and re-cultured or used in downstream applications.  If the number of migratory cells recovered is important for the downstream application, keep in mind that only 5% of cells are expected to migrate with even a highly migratory cell line, so we recommend starting the assay with the maximum number of cells.