Discovery Of Properties Of MAIT Cells During HIV Infection Can Facilitate Future Therapeutics
Source: Thailand Medical News Jan 21, 2020 4 years, 10 months, 17 hours, 44 minutes ago
A novel study by researchers from Karolinska Institutet show that
mucosa-associated invariant T cells (
MAIT cells) of the human
immune system respond with dynamic activity and reprogramming of gene expression during the initial phase of
HIV infection. The study fills a knowledge gap, as previously, the function of
MAIT cells during this particular phase was not well understood.
Enormous efforts have been made in recent years to understand how people's
immune systems react and act during the first days and weeks of
HIV infection.
Dr Johan Sandberg, Professor at the Department of Medicine at Karolinska Institutet in Huddinge and senior author of the study told
Thailand Medical News, "Through a close collaboration with the Walter Reed Army Institutes of Research, we have gained access to an extensive biobank where we have been able to study samples from individuals, both before and after they have been infected with
HIV."
Typically,
MAIT cells are part of the
immune system and their primary task is to control bacteria at the body's barriers, such as skin and mucous membranes.
Among other things,
MAIT cells have an important function in combating bacterial infections of the lung, for example, tuberculosis. However,
MAIT cells also respond during an
HIV infection, even though it is a viral infection. This is probably because the
immune systems of infected individuals lose control over bacteria when infected.
Dr Sandberg added, "Previous observations have shown that
MAIT cells disappear in the later stages of
HIV infection. In this study, we can see that the
MAIT cells actually expand at the initial stage with a strong activation in order to fight the bacteria."
Though
MAIT cells may not help to control the
HIV virus to any great extent, when the infection becomes chronic, the number of
MAIT cells in the body decreases. Unlike many other parts of the body's
immune system,
MAIT cells do not recover when the
HIV infection is treated.
Dr Johan Sandberg further added, "In the study, we also discovered that the gene expression patterns of the
MAIT cells change gradually during the initial phase. They take on different characteristics and their antibacterial function declines, which can affect the individual's
immune defence in a negative way."
The research study increases the understanding of what happens at the initial phase of
HIV infection. Knowledge has previously been lacking in this area, as the individuals diagnosed with
rong>HIV had often been infected for a longer time when the research began.
Dr Sandberg commented, "In the HIV research that is currently being conducted, the focus is on developing vaccines and finding cures. Knowledge of how the immune system works in the initial phase of HIV infection, such as the activity and properties of the MAIT cells, can facilitate the finding of future interventions."
Reference: Dynamic MAIT cell response with progressively enhanced innate-like features during acute HIV-1 infection, Nature Communications, Jan. 14, 2020, DOI: 10.1038/s41467-019-13975-9