Purity ~95% (SDS-PAGE). CCL21, which is a member of the family of CC-Chemokines, has a unique 36 (murine) or 37aa (human) C-terminal extension not seen in other chemokines. CCL21 selectively stimulates the chemotaxis of adult T lymphocytes and is expressed preferentially in lymph node tissue. CCL21 is critical for adult T cell adhesion to high endothelial venules in lymph nodes, a rate-limiting step for T cell trafficking through nodal tissue. Source: Recombinant protein corresponding to human CCL21 expressed in E. coli. Molecular Weight: ~12kD Biological Activity: Determined by its ability to chemoattract total lymphocyte population using a concentration range of 10-100ng/mL. Endotoxin: <1EU/ug (LAL)