Study Reveals Cholesterol Clusters as a Key Entry Point for SARS-CoV-2 into Cells

A recent study unveiled the doorway that SARS-CoV-2 uses to slip inside cells undetected. The receptor angiotensin-converting enzyme 2 (ACE2) is known to be involved in the virus's entry into human cells, but the exact mechanism remained unclear. In a breakthrough discovery, Scott Hansen and his team at the University of Florida Scripps found that cholesterol clusters act as the door that allows the virus to enter cells. The study, published in the Journal of Biological Chemistry, sheds light on the importance of cholesterol in facilitating viral infection.

During the early stages of the COVID-19 pandemic, it was observed that the elderly and individuals with chronic diseases were more susceptible to severe viral-related outcomes, while children appeared to be less affected. Hansen hypothesized that the abundance of tissue cholesterol in populations with chronic diseases could play a role in this phenomenon. Studies using advanced techniques, including super resolution microscopy, revealed that cholesterol on the cell surface makes ACE2 readily accessible to SARS-CoV-2, enabling viral entry.

The team's findings suggest that excessive cholesterol levels may increase the risk of COVID-19 at the cellular and biochemical levels. For instance, smokers with chronic diseases were found to have elevated cholesterol levels in lung tissue, which significantly increased viral infectivity. However, Hansen's previous research indicates that cholesterol-dependent SARS-CoV-2 infection can be disrupted through interventions like exercise. Mechanical force and polyunsaturated fatty acids can help prevent cholesterol aggregation, promoting cellular health and reducing the risk of infection.

In addition to unraveling the entry mechanism of SARS-CoV-2, Hansen's study also highlighted the limitations of current cholesterol assessment methods used by doctors. Blood tests, which are commonly employed, only provide a snapshot of cholesterol levels and fail to capture its distribution and activity within tissues. Hansen and his team are collaborating with physicians to develop a more accurate test that reflects tissue cholesterol and its dynamics throughout the body. This shift in cholesterol assessment could lead to a better understanding of disease risk and potentially save lives.