Role of the Immune System in Hypertension

Area of Science:

• Cardiovascular immunology
• Renal physiology
• Immunopathology

Background:

• Hypertension affects over one billion adults globally, representing a major modifiable risk factor for cardiovascular disease mortality.
• While multifactorial, the immune system's involvement in hypertension pathogenesis is increasingly recognized.
• Immune system activation, involving both innate and adaptive immunity, triggers inflammation, oxidative stress, and intrarenal angiotensin system stimulation, contributing to high blood pressure.

Purpose of the Study:

• To explore the established role of the immune system in the development and progression of hypertension.
• To highlight how immune cell infiltration and inflammatory responses contribute to hypertensive organ damage.
• To identify potential novel therapeutic targets within the immune system for hypertension treatment.

Main Methods:

• Review of experimental and human studies investigating the immune system's contribution to hypertension.
• Analysis of data from immunosuppressive drug trials and cytokine inhibition studies in experimental hypertension models.
• Examination of genetically-modified mouse models to assess the necessity of lymphocytes in hypertension development.

Main Results:

• Immunosuppressive drugs and cytokine inhibition ameliorate experimental hypertension.
• Lymphocytes are essential for the development of hypertension and associated organ injury in mouse models.
• Immune cell infiltration, oxidative stress, and intrarenal angiotensin system activation are consequences of innate and adaptive immunity activation.
• Hypertension arises from inflammation-impaired pressure natriuresis, reduced vascular relaxation, and sympathetic nervous system overactivity.
• Regulatory T cell balance dictates inflammation severity, with identified autoantigens like isoketal-modified proteins and heat shock protein 70.

Conclusions:

• Immune system dysregulation is a key driver of hypertension and its target organ damage.
• Therapeutic strategies targeting immune pathways, including regulatory T cells and identified autoantigens, hold promise for novel hypertension treatments.