CD103 Regulates Dermal Regulatory T Cell Motility and Interactions with CD11c-Expressing Leukocytes to Control Skin...

Area of Science:

• Immunology
• Dermatology
• Cell Biology

Background:

• Dermal regulatory T cells (Tregs) are vital for skin homeostasis and immune responses.
• CD103, an integrin highly expressed by skin Tregs, is thought to promote their retention in the skin.
• The interaction mechanism between CD103 on Tregs and its ligand E-cadherin in the dermis remains unclear.

Purpose of the Study:

• To investigate the role of CD103 in regulating dermal Treg behavior during skin inflammation.
• To elucidate the mechanism by which CD103 influences Treg migration and interaction with other immune cells in the skin.

Main Methods:

• Multiphoton intravital microscopy was used to observe Treg behavior in mouse skin.
• Contact hypersensitivity was induced using oxazolone.
• CD103 function was inhibited to assess its impact on Treg migration and interactions.

Main Results:

• CD103 inhibition increased Treg migration in inflamed skin, specifically at later stages of inflammation.
• This correlated with increased E-cadherin expression on dermal myeloid leukocytes.
• CD103 inhibition reduced Treg interactions with dermal dendritic cells and increased effector CD4+ T cell recruitment.

Conclusions:

• CD103 controls intradermal Treg migration, particularly during later inflammatory phases when E-cadherin is upregulated in the dermis.
• CD103-mediated interactions between Tregs and dermal dendritic cells are important for regulating skin inflammation.