CD4 Fab-TACS® Magnetic Microbead Starter Kit, human

Fab-TACS® - Traceless Affinity Cell Selection - is a positive cell isolation approach based on our Strep-tag® technology. CD4 Fab-TACS® Magnetic Microbead Starter Kit allows label-free isolation of human CD4+ T helper cells from peripheral blood mononuclear cells (PBMCs). CD4 is a co-receptor that associates with the T cell receptor and interacts with MHC class II molecules.

Low affinity Fab fragments fused to a Twin-Strep-tag® (Fab-Streps) are incubated with Strep-Tactin® Magnetic Microbeads to form a complex that stably binds to the cell surface. After specific labeling, target cells are bound to a magnet and non-target cells efficiently washed away. In a final step, the addition of biotin causes the release of the isolated cells from magnetic microbeads. The Fab-Streps self-dissociate from the cell surface due to their low affinity. After removing biotin by washing, the isolated cells are ready for further positive selection or depletion steps or can directly be used for further downstream applications.

Advantages:

• High purity of > 90%
• Scalable reagents
• Label-free cells due to low affinity Fab fragments
• Non-activated cells

The kit contains:

• Strep-Tactin® Magnetic Microbeads
• CD4 Fab-Strep, human • 10x Buffer CI
• Biotin stock solution

For total cell numbers higher than 1 x 10⁸, we recommend our Strep-Tactin® TACS Agarose columns that have a capacity of 1 x 10⁹ total cells and can bind up to 1 x 10⁸ target cells.