T cells in arteritis and atherosclerosis.

Area of Science:

• Immunology
• Vascular Biology
• Pathology

Background:

• Inflammatory vasculopathies, including atherosclerosis and vasculitides, involve complex innate and adaptive immune responses.
• T cells, guided by antigen-presenting cells, play a critical role in orchestrating both protective and detrimental immunity within the vasculature.

Purpose of the Study:

• To review the role of T cells and antigen-presenting cells in inflammatory vasculopathies.
• To explore how the arterial microenvironment influences T cell responses.
• To identify potential immunotherapeutic targets for vascular diseases.

Main Methods:

• Review of current literature on T cell and dendritic cell function in vascular inflammation.
• Analysis of immune cell interactions within the arterial wall.
• Examination of signaling pathways involved in T cell activation and effector function.

Main Results:

• Dendritic cells within the arterial wall are key in initiating and sustaining T cell responses.
• Both antigen-specific and antigen-nonspecific factors, along with dysregulated signaling, contribute to T cell hyperresponsiveness.
• Pathogenic T cells promote vascular injury through macrophage activation and direct induction of smooth muscle cell apoptosis via TRAIL.

Conclusions:

• Innate immune cells, particularly dendritic cells, are present in arteries and direct T cells towards pro-inflammatory and destructive functions.
• The unique arterial microenvironment shapes immune responses across various vascular diseases, including atherosclerosis and arteritis.
• These findings provide a framework for developing novel immunotherapies targeting T cell-mediated vascular inflammation.