In a recent study, MU researchers found a link between a T-cell membrane protein and HIV infectivity.
Shan-Lu Liu, associate professor of molecular microbiology and immunology and an investigator with the Bond Life Sciences Center, and graduate student Minghua Li were studying the role of transmembrane, immunoglobulin and mucin (TIM) family proteins in the immune system and suspected the TIM-1 protein is involved in viruses’ entry into cells.
“While we were working on the possible role of the TIM-1 protein in viral entry, we found, by accident, this protein actually blocked HIV release,” Liu said.
The research team went on to prove the discovery by studying the protein and HIV very carefully. A collaboration with Eric Freed from the National Cancer Institute was a vital part in discovering how and where the TIM-1 protein worked. Freed helped the team discover that the protein was trapping the virus on the membrane of the cells.
“You have to be prepared (for the unexpected),” Liu said. “We look at the data very carefully.”
The TIM-1 protein has the ability to cross-link with the chemical compound phosphatidylserine, making the cell membrane stronger and more rigid. Membrane strength aids the cell in preventing viruses, such as HIV-1 and Ebola, from being released.
“We spent a lot of time to find the mechanism behind the phenomenon — how and why TIM-1 can inhibit HIV and a broad reach of other viruses,” Li said.
However, the researchers said they could not be certain this prevented the virus from spreading. To further explore the biological role of the TIM-1 protein, they are looking into what happens after the protein prevents the virus from being released.
“Regardless of if (the protein has) a positive effect or a negative effect, we will gain the knowledge of the TIM protein in terms of viral infection and other biological functions,” Liu said.
An understanding of the TIM-1 protein could be a factor in future HIV treatment. While it may not provide a cure or treatment, the study provides important information and an exciting opportunity to the researchers.
“We did not plan to work on HIV so quickly,” Liu said. “Now that we found this, half of the people in the lab are working on HIV.”