In the ultimate superhero crossover, Spider-Man-like immune cells sling the web to capture invasiveness. Bacteria And new studies show that they continue to restrain their supervillains until cells like Pac-Man begin to devour them.
The study was conducted in mice, mouse Although cells, they may help explain how these “Spider-Man” cells, called neutrophils, fight human infections and why they fail.After all, these spy cells may not work well in people with autoimmune conditions such as: Lupus, Making those individuals more vulnerable to staphylococcal infections, the study authors wrote.
When staphylococcal infections first began to settle in the body, neutrophils in our friendly neighborhood swooped in as first responders. Staphylococcus aureus Eric Skar, senior author and director of the Vanderbilt Institute for Infection, Immunology and Inflammation in Nashville, Tennessee, told Live Science. These neutrophils have secret weapons. The sticky web can be self-destructed and expelled from the ruptured membrane.This web, called neutrophil extracellular traps (NETs), contains neutrophils. DNA It is studded with proteins that break down bacteria.
Researchers have previously discovered that NET has a chemical danger signal that encourages macrophages (white blood cells that devour bacteria) to spark. inflammation At the site of infection Scientists reported.. However, new studies also show that the two cell types work together to initiate a coordinated attack on invading microorganisms, Skaar said. Neutrophils cast the NET to immobilize the bad guys, and macrophages plunge and swallow the entire bug. It’s the same as Pac-Man devouring ghosts.
While eating the catch, macrophages “actually remove this huge bite from the net,” Scar said. The NET antibacterial protein then mixes with the antibacterial protein already present in the “belly” of macrophages, so the two cell types come together to break down bacteria more effectively than either cell alone. ..
In a recent mouse study led by postdoctoral fellow at Vanderbilt University, Andrew Monteis, the team found that some neutrophils release NET faster than others when chasing staphylococci. discovered. Specifically, a protein called S100A9 determines how fast neutrophils sling the spider web. Mice with low levels of this protein Methicillin resistance Staphylococcus aureus (MRSA), the team showed in a study published in the journal in 2017 Cell hosts and microorganisms..
In their new study, researchers began to focus on why: When neutrophils low in this protein encounter staphylococci, their Mitochondria — So-called cell power plant — leaks electrons and produces harmful substances Free radicals In the cell. This will cause the cell to self-destruct and free the NET. This ultra-fast NET casting enhances the ability of neutrophils and macrophages to remove staphylococci from the body as a duo that fights bacteria.
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The same was true when the team attacked immune cells. Streptococcus pneumoniaeIt can infect many organs in the body, including the lungs and brain.And they found the same result again Pseudomonas aeruginosaA common cause of nosocomial infections that can affect the lungs, bones and other organs.
Lupus erythematosus Rheumatoid arthritisIn theory, neutrophils could release NETs more slowly than average, because they produce more S100A9 than those without these conditions, Skaar said. “This may partially explain why they are more susceptible to staphylococci than the general public,” he said. However, the team still needs to confirm this theory in humans.
“Of course, putting everything in the mouse is a big limitation,” Scarr said.
In addition to investigating this potential association with autoimmune disease, the team plans to study exactly why S100A9 affects the rate at which neutrophils develop sticky NETs. doing. Scientists can then enhance the ability of neutrophils to web sling and strengthen their ability to fight infection.
The study was published in the journal on Friday (September 10th) Science Advances..
Originally published in Live Science.
How “Spider-Man” and “Pac-Man” immune cells work together to fight invading bacteria
Source link How “Spider-Man” and “Pac-Man” immune cells work together to fight invading bacteria