Albumin: A Key Player in Fighting Deadly Black Fungus

An international team of scientists has discovered that albumin, the most abundant protein in human blood, plays a critical and previously unrecognized role in protecting the body from mucormycosis, a rare but often fatal fungal infection. The groundbreaking findings, published in Nature, could lead to new strategies for preventing and treating this devastating disease.

Understanding Mucormycosis

Mucormycosis, commonly known as “black fungus,” is caused by fungi belonging to the Mucorales order. The infection can spread rapidly throughout the body and is fatal in up to half of cases, with some patients facing an almost certain risk of death. A surge in cases was observed during the COVID-19 pandemic, particularly in individuals with diabetes, weakened immune systems, or malnutrition.

The Link Between Low Albumin and Severe Outcomes

Researchers found a strong correlation between low albumin levels (hypoalbuminemia) and increased risk of death in mucormycosis patients. Across multiple patient groups on different continents, hypoalbuminemia emerged as the strongest predictor of severe outcomes. This suggests that albumin levels could serve as a crucial biomarker for identifying individuals at high risk of developing aggressive infections.

“This is a remarkable finding and has the potential to change the way clinicians care for mucormycosis,” said Dr. Ashraf Ibrahim, a senior author of the study from The Lundquist Institute for Biomedical Innovation.

How Albumin Fights Fungal Invasion

The study revealed that albumin selectively inhibits the growth of Mucorales fungi without harming other microbes. Laboratory tests demonstrated that when albumin was removed from human blood samples, the fungus multiplied rapidly. Conversely, mice lacking albumin were highly susceptible to infection, while restoring albumin levels provided significant protection.

Further investigation showed that albumin’s antifungal activity relies on fatty acids bound to the protein. These fatty acids disrupt fungal metabolism and block the production of proteins necessary for tissue invasion and disease progression. Notably, blood samples from patients with mucormycosis exhibited higher levels of fatty acid oxidation, potentially explaining their increased vulnerability to infection.

A Novel Host Defense Mechanism

The research unveils a previously unknown natural defense mechanism within the human body. The findings suggest that therapies based on albumin could offer a new approach to preventing or treating mucormycosis, a disease with limited effective treatment options currently available.

Researchers at The Lundquist Institute are exploring the possibility of combining albumin treatment with immunotherapies targeting Mucorales virulence factors.

Research Origins

Breakthrough research performed at the University of Crete School of Medicine and collaborators, lead by Professor George Chamilos, was published in Nature.