# An Exploratory Study of the Impact of a CCL21‐Derived C‐Terminal Peptide on Dendritic Cell Lymph Node Homing

## TL;DR

This study explores how a CCL21-derived peptide improves dendritic cell migration to lymph nodes, potentially enhancing immunotherapies.

## Contribution

The study introduces C21TP, a CCL21-derived peptide that enhances dendritic cell homing to lymph nodes without cellular modifications.

## Key findings

- C21TP boosts CCL21-mediated signaling and chemotaxis of dendritic cells in vitro.
- DCs formulated with C21TP migrate more efficiently to lymph nodes in vivo compared to controls.
- C21TP offers a practical approach for improving dendritic cell-based immunotherapies.

## Abstract

The effective trafficking of dendritic cells (DCs) to the lymph nodes (LNs), orchestrated by CC‐chemokine receptor 7 (CCR7) and its ligand CCL21, is essential for the success of DC–based immunotherapies. This study explores the potential of C21TP, a naturally occurring basic peptide derived from the C‐terminal of CCL21, to enhance DC homing to the draining LNs in a murine model of DC migration. C21TP, containing three clusters of basic residues, significantly boosts CCL21‐mediated signaling and chemotaxis of DCs in vitro. In vivo, DCs formulated with C21TP prior to injection migrated more efficiently to the draining LNs than DCs alone or DCs formulated with a mutated version of C21TP, harboring substitutions in key basic residues. Further studies are needed to evaluate the impact of C21TP on T‐cell priming efficacy in the context of DC–based immunotherapies. Nonetheless, C21TP’s ability to enhance lymph node homing of adoptively transferred cells without additional cellular modifications could offer a practical and scalable approach for advancing future DC–based vaccines.