T Cells Control Chemokine Secretion by Keratinocytes

Area of Science:

• Immunology
• Dermatology
• Molecular Biology

Background:

• Lymphocyte infiltration is characteristic of many skin disorders.
• The communication between lymphocytes and skin cells is crucial for immune responses.

Purpose of the Study:

• To investigate the molecular mechanisms by which T cells regulate keratinocyte chemokine production.
• To elucidate the role of T cell-derived factors in modulating skin inflammation.

Main Methods:

• Co-culture of murine keratinocytes with splenic T cells.
• Analysis of chemokine synthesis and gene expression.
• Investigation of NFAT factors and Interferon-gamma (IFN-γ) in T cells.

Main Results:

• Pre-activated CD8+ T cells induce CXCL9 and CXCL10 in keratinocytes, while suppressing CXCL1, CXCL5, and CCL20.
• Keratinocytes reduce CCL3 and CCL4 synthesis in T cells.
• IFN-γ, regulated by NFATc1/NFATc2, is essential for T cell-induced chemokine expression.
• T cells induce type I IFN-inducible genes in keratinocytes, mirroring patterns in lichen planus.

Conclusions:

• T cells dynamically control keratinocyte chemokine profiles.
• NFAT-dependent IFN-γ production by T cells is a key mediator of this interaction.
• The findings provide molecular insights into T cell-keratinocyte crosstalk in inflammatory skin conditions.