Insights into CCL21's roles in immunosurveillance and immunotherapy for gliomas

- CCL21 may have reparative capacity in the setting of tumor-induced damage.
- CCL21 may regulate migration of circulating leukocytes into CNS during inflammation.
- CCL21 inhibition of tumor growth has been observed in several non-CNS cancers.
- Treatment of glioma with CCL21 has yet to be described.

Chemokine (C-C) motif ligand 21 (CCL21) is involved in immunosurveillance and has recently garnered the attention of neuro-oncologists and neuroscientists. CCL21 contains an extended C-terminus, which increases binding to lymphatic glycosaminoglycans and provides a mechanism for cell trafficking by forming a stationary chemokine concentration gradient that allows cell migration via haptotaxis. CCL21 is expressed by endothelial cells of the blood-brain barrier in physiologic and pathologic conditions. CCL21 has also been implicated in leukocyte extravasation into the central nervous system. In this review, we summarize the role of CCL21 in immunosurveillance and explore its potential as an immunotherapeutic agent for the treatment of gliomas.