IL-17-producing γδ T cells switch migratory patterns between resting and activated states

Area of Science:

• Immunology
• Cell Biology
• T cell biology

Background:

• Interleukin 17-producing γδ T (γδT17) cells are key players in immunity and disease.
• Their migration to barrier tissues and inflamed sites is critical but poorly understood.
• Understanding γδT17 cell trafficking is essential for controlling immune responses.

Purpose of the Study:

• To elucidate the migratory cues controlling γδT17 cell positioning and recruitment.
• To define the roles of chemokine receptors in γδT17 cell trafficking.
• To establish a model for γδT17 cell homing to tissues.

Main Methods:

• Analysis of chemokine receptor expression (CCR6, CCR2) on γδT17 cells.
• Investigating the role of IRF4 and BATF in receptor regulation.
• Studying γδT17 cell recruitment in models of autoimmunity, cancer, and infection.

Main Results:

• γδT17 cells constitutively express CCR6 and CCR2.
• CCR6 mediates homing of resting γδT17 cells to the dermis.
• CCR2 drives rapid recruitment of activated γδT17 cells to inflamed tissues.
• IRF4 and BATF downregulate CCR6 on activated γδT17 cells, enabling inflammatory site recruitment.

Conclusions:

• A dynamic hierarchy of chemokine receptor expression governs γδT17 cell trafficking.
• CCR6 and CCR2 play distinct roles in tissue surveillance and inflammatory recruitment.
• This lymphocyte trafficking model highlights the importance of regulated receptor expression for immune cell positioning.