The Big Question 

What if we could make the invisible lymphatic system visible? 

The Problem 

Though invisible to the naked eye, the lymphatic system plays a major role in the healthy function of all major organs. Patients with primary lymphatic disease (LD) are often misdiagnosed, leading to inappropriate treatments, prolonged hospital stays, possible disfigurement and disability, and even death.  

Beyond LD, this difficulty in assessing lymphatic health impairs our understanding of its role in a variety of common, chronic diseases. Cancer, obesity, heart failure, inflammatory bowel disease, chronic kidney and liver diseases, autoimmune disorders, and neurodegenerative diseases all have a lymphatic component.  

The Current State 

Signs of LD only appear clearly when the disease progresses, and clinical symptoms can be subtle or overlap with other conditions. The primary way to diagnose lymphatic dysfunction is a physical evaluation, which is not standardized and provides no insight into lymphatic anatomy or function. Today, reliable visualization is a major challenge in assessing lymphatic dysfunction. 

Current imaging technologies for the lymphatic system all have drawbacks. Magnetic resonance imaging, for example, is highly specialized, expensive, and inaccessible to most patients. More affordable imaging techniques lack good tissue penetration or are insufficiently detailed to be widely useful. Measurements from blood and lymphatic fluid and genetic testing have not been fully explored.  

The Challenge 

Lymphatic vessels are tiny and translucent, making them much harder to see than blood vessels. Lymph fluid moves through them at a slow rate and low pressure, preventing many of the diagnostic techniques used for veins and arteries from being effective. Lymph fluid itself is also highly variable in composition.  

The Solution 

The Lymphatic Imaging, Genomics, and pHenotyping Technologies (LIGHT) program seeks comprehensive diagnostic solutions across three technical areas: diagnosis and monitoring through biomarker discovery; imaging technologies; and prevention, prediction, and diagnostic confirmation through genetics, epigenetics, and models of lymphatic dysfunction. If successful, LIGHT will not only illuminate the unseen aspects of the lymphatic system through novel diagnostic approaches, but also significantly improve patient care and outcomes by gaining a deeper understanding of its critical role in health. 

Why ARPA-H? 

ARPA-H is always seeking unconventional approaches and innovative solutions to pressing health challenges. LIGHT targets an overlooked system in order to catalyze transformative advances in lymphatic medicine.