STEMCELL Technologies offers kits for isolating human Th17 cells, Memory B cells and CD4+CD25+ T cells. These kits involve a two step separation process: a pre-enrichment negative selection, followed by a positive selection step. For the pre-enrichment step, there is a recommended start sample concentration for your cell suspension, with a specified maximum cell number. There is also a recommended range of working volumes that is appropriate for the magnet that you are working with. Once the pre-enrichment step is complete, there is no need to count your cells.The enriched cells can simply be re-suspended in the recommended volume before proceeding with the positive selection step.

These kits and protocols have been rigorously tested, optimized, and validated in house. The recommended amount of positive selection cocktail added for selecting your cell type of interest is appropriate for the complete range of cell concentrations that may result after re-suspending your pre-enriched sample. The following tables summarize the recommended re-suspension volumes that have been validated, based on the starting sample size and the magnet used, for each of these multi-step isolation kits.

Magnet	Pre-Enrichment		CCR6+ Selection
	Starting Cell #	Volume	Re-suspension Volume
Purple	≤ 1.0 x 108	0.5 - 2.0 mL	250 µL
Silver / RoboSep™	≤ 1.25 x 108	0.5 - 2.5 mL	250 µL
	>1.25 x 108 – 2 x 108	>2.5 - 4.0 mL	500 µL
	>2 x 108 – 4 x 108	>4.0 - 8.0 mL	1.0 mL

EasySep™ Human Memory B Cell Isolation Kit (Catalog #18164):

Magnet	Pre-Enrichment		CD27+ Selection
	Starting Cell #	Volume	Re-suspension Volume
Purple	≤ 1.0 x 108	1.0 - 2.0 mL	250 µL
Silver / RoboSep™	≤ 1.0 x 108	1.0 - 2.0 mL	250 µL
	> 1.0 x 108 – 4 x 108	> 2.0 - 8.0 mL	400 µL

Magnet	Pre-Enrichment		CD25+ Selection
	Starting Cell #	Volume	Re-suspension Volume
Silver / RoboSep™	≤ 7.5 x 108	0.5 - 15 mL	500 µL

Magnet	Pre-Enrichment	CD25+ Selection (using EasySep™ Kit #18231)
	Starting Cell Volume	Re-suspension Volume
Purple	1.0 mL - 500 mL	500 µL
Silver / RoboSep™	1.0 mL - 500 mL	500 µL

For further assistance and information on any of these EasySep kits, please contact techsupport@stemcell.com.