Chemokines
Product List
Exodus 2 Mouse
Exodus-2 Mouse Recombinant (CCL21)
Exodus 2 Human
Exodus-2 Human Recombinant (CCL21)
Introduction
Exodus-2, also known as C-C motif chemokine ligand 21 (CCL21), is a small cytokine belonging to the CC chemokine family. It is also referred to as 6Ckine, secondary lymphoid-tissue chemokine (SLC), and thymus-derived chemotactic agent 4 (TCA-4) . CCL21 is characterized by six conserved cysteine residues, which is a distinctive feature of this chemokine family .
Key Biological Properties: CCL21 is a 12.2 kDa protein composed of 111 amino acids . It contains an extended C-terminus rich in positively charged residues, which gives it a high affinity for negatively charged molecules in the extracellular matrix .
Expression Patterns and Tissue Distribution: CCL21 is constitutively expressed in lymphoid tissues, including lymph nodes, spleen, and Peyer’s patches . It is produced by high endothelial venules, lymphatic endothelial cells, and stromal cells within T-cell areas of lymph nodes . Its expression increases during inflammation .
Primary Biological Functions: The main function of CCL21 is to guide CCR7-expressing leukocytes to secondary lymphoid organs, such as lymph nodes and Peyer’s patches . It plays a crucial role in the recruitment of T cells and dendritic cells to these organs .
Role in Immune Responses and Pathogen Recognition: CCL21 is involved in the chemotactic migration of T cells and the cell adhesion caused by integrin activation . It also plays a role in the migration of dendritic cells to secondary lymphoid organs, which is essential for initiating immune responses .
Mechanisms with Other Molecules and Cells: CCL21 exerts its effects by binding to the chemokine receptor CCR7 . This interaction guides leukocytes to secondary lymphoid organs .
Binding Partners and Downstream Signaling Cascades: The binding of CCL21 to CCR7 triggers downstream signaling cascades that lead to the chemotactic migration and adhesion of T cells . The extended C-terminus of CCL21 allows it to bind to glycosaminoglycans and endothelial cells, enhancing its chemotactic properties .
Regulatory Mechanisms Controlling Expression and Activity: CCL21 is classified as a homeostatic chemokine, meaning it is produced continuously, but its expression increases during inflammation . The cleavage of its C-terminal tail by peptidases produces a soluble form of CCL21, which has different functions compared to the full-length protein .
Transcriptional Regulation and Post-Translational Modifications: The gene encoding CCL21 is located on human chromosome 9 . Post-translational modifications, such as the cleavage of the C-terminal tail, play a significant role in regulating its activity .
Biomedical Research: CCL21 is widely used in research to study immune cell migration and the mechanisms of immune responses .
Diagnostic Tools: ELISA kits for detecting CCL21 levels in serum, plasma, and cell culture media are available and used in various research applications .
Therapeutic Strategies: CCL21 has potential therapeutic applications in cancer immunotherapy, where it can enhance the expansion and cytotoxic potency of antigen-specific T cells .
Role Throughout the Life Cycle: CCL21 plays a critical role in the development and function of the immune system throughout life. It is involved in the homeostatic trafficking of lymphocytes and the organization of lymphoid structures . Its expression and function are crucial during immune responses, inflammation, and in the context of diseases such as cancer .
