Vascular Regenerative Cell Exhaustion in Adults with Peripheral Artery Disease (PAD-VRCE)

This study examines how "vascular regenerative cells" — a type of cell that helps repair blood vessels — behave in people with peripheral artery disease (PAD), a condition where narrowed arteries reduce blood flow to the legs. Researchers are comparing these cells in people with and without PAD to understand disease progression. **You may be eligible if...** - You are between 18 and 80 years old - You have PAD with leg pain during walking and a low ankle-brachial index (less than 0.85), OR you have no history of PAD - You are able and willing to provide a blood sample and give written consent **You may NOT be eligible if...** - You have uncontrolled high blood pressure - You have an active or uncured cancer (excluding non-melanoma skin cancer cured more than 5 years ago) - You have a life-threatening illness expected to cause death within 2 years - You have advanced heart failure Talk to your doctor to see if this trial is right for you.