A molecular traffic controller for the immune system
Dendritic cells, the sentinels of the immune system, must migrate from tissues to lymph nodes to activate T-cells. This journey is guided by the chemokine CCL21. New research reveals a sophisticated regulatory switch: a protease called uPA, active on lymphatic vessel cells, cleaves a stationary form of CCL21 into a soluble, mobile variant. During inflammation, this cleavage is amplified, reshaping the chemical landscape to facilitate dendritic cell entry into lymphatic vessels while also fine-tuning their exit into the lymph node. This precise, enzyme-driven remodeling of guidance cues is a critical checkpoint in initiating adaptive immunity.
Why it might matter to you:
This work uncovers a fundamental, tunable mechanism controlling immune cell trafficking, a process central to both vaccine efficacy and inflammatory disease. Understanding how proteases like uPA regulate chemokine gradients could inform the design of next-generation adjuvants that precisely direct dendritic cell migration. Furthermore, it reveals a potential therapeutic axis for modulating unwanted immune cell infiltration in conditions like chronic inflammation or transplant rejection.
Stay curious. Stay informed — with
Science Briefing.
Always double check the original article for accuracy.