Anti-bacterial T Cells, MAIT Cells are Strongly Activated in People with Moderate to Severe COVID-19 Disease, Study Suggests

Jan, 2021 - By SMI

According to a new study by the researchers of Karolinska Institutet have reported that MAIT cells, a type of anti-bacterial T cells are intensely activated in people suffering from moderate to severe COVID-19 disease. Researchers also noted that the outcomes can aid in detailed understanding about how our immune system reacts against COVID-19 infection. Moreover, T cells are type of white blood cells that aids in detecting infected cells and are vital part of the immune system. In healthy individual, around 1 to 5% of T cells in the blood of healthy people are MAIT cells that aids in controlling bacteria but sometimes immune system use this specific cells to fight against some viral infections.

In this study, researchers focused on MAIT cells and what role they play in the pathogenesis of COVID-19 disease. Researchers considered 24 patients who were admitted in the hospital due to moderate to severe COVID-19 disease, and evaluated the presence and character of MAIT cells in their blood samples. Later researchers compared the infected blood samples with blood samples from 14 healthy controls and 45 individuals who recovered from COVID-19.

Researchers observed that the number of MAIT cells in the blood declined severely in patients with moderate or severe COVID-19 and cells that remained in the circulation were highly activated, indicating that they are engaged in the immune response against SARS-CoV-2. Furthermore, researchers also found that pro-inflammatory MAIT cells mounted up in the airways of COVID-19 patients more notably in comparison to healthy people.

Johan Sandberg stated, "The findings of our study show that the MAIT cells are highly engaged in the immunological response against COVID-19. There, they are likely to contribute to the fast, innate immune response against the virus. In some people with COVID-19, the activation of MAIT cells becomes excessive and this correlates with severe disease.”