A new study finds that T cells, not viruses, are responsible for Zika andThe main culprit in neurological damage in diseases such as COVID-19 has led to new treatment strategies.For years, it has been thought that acute viral infections such as Zika or COVID-19 were the direct cause of neurological damage, but researchers at McMaster University have now found that it is the immune system's response that is behind this.

The research published today (February 5, 2024) in Nature Communications was led by Elizabeth Balint, a doctoral student at McMaster University, and Ali Ashkar, professor in the Department of Medicine and Canada Research Chair in Innate Immunity and NK Cell Function.

"We are interested in understanding why so many viral infections are associated with neurological disease," Balint said. "Our evidence suggests that it is not the virus itself that causes the damage, but a unique population of T cells that are part of the immune system and that they are actually responsible for the damage."

To reach this conclusion, McMaster's team focused on the Zika virus. In laboratory tests, the researchers unsurprisingly found Zika-specific T cells designed to destroy infected cells. They also discovered something else.

"What's interesting in our study is that while we did find some T cells specific to Zika, we also found some cells that didn't function like normal T cells and were killing large numbers of cells that were not infected with Zika."

These cells are called NKG2D+CD8+ T cells, and the researchers say their aggressive response is responsible for damage to the nervous system, and not just Zika virus infections, such as COVID-19 or even septic shock.

Immune response and potential treatments

Moderate amounts of cytokines help coordinate the body's response to infection or injury, telling immune cells where to go and what to do when they arrive.

"If the immune cells in our body overreact and overproduce inflammatory cytokines, this situation will lead to non-specific activation of immune cells, which can lead to collateral damage. If this happens in the brain, it can have serious consequences," Ashkar said.

The discovery provides researchers and scientists with a new target for treating neurological diseases caused by acute viral infections. In fact, Balint has found a promising treatment.

"Elizabeth has tested an antibody that can completely block and treat damaging neurotoxicity in animal models, and this antibody is already in clinical trials for different uses in humans," Ashkar said.

Balint hopes to continue efforts to find an effective treatment in humans: "We are interested in studying several other different viruses, which will help us develop the best treatment options."

Compiled source: ScitechDaily