Infected wounds pose a significant mortality risk to animals. Injuries are common in Matabeleari (Megaponera analis), raiding warlike prey. New research shows that these predatory ants can tell when a wound has become infected and treat it accordingly. Workers apply various antimicrobial compounds and proteins secreted from the retropleura to infected wounds, reducing mortality rates in infected individuals by 90%.
Matabeleari (Megaponera analis) He cares for the wound of a fellow ant whose leg was bitten off during a fight with termites. Image credit: Erik Frank / University of Würzburg.
Infectious diseases are a major mortality risk for animals, and animals that live in groups are particularly at risk of contracting life-threatening contagious pathogens.
This has led to a series of pathogen-induced changes in social interactions, including social distancing, disease signaling, and medical care.
Injured people are an easy entry point for life-threatening infections because their primary barrier to infection, the epidermis, or epidermis, is damaged.
Recently, some mammals have been shown to lick wounds to apply antiseptic saliva. However, the effectiveness of these actions remains largely unknown and occurs regardless of wound status.
In social insects, interactions to combat pathogens range from preventive measures such as nest disinfection and conspecific grooming, to dying individuals leaving the nest and dying in isolation, to destructive disinfection of infected mates. It's wide-ranging.
However, whether and how social insect colonies care for injured individuals exposed to pathogens is still poorly understood.
Predatory Matabele ant workers have been known to treat injuries to their nestmates, a common occurrence since the ants only feed on belligerent termites. As many as 22% of collectors engaged in termite raids lose one or two of their legs.
Injured workers are carried to the nest, and for the first three hours after injury, other workers treat the wound by licking and grooming the wound.
If the wounds of injured workers are not treated by nestmates, 90% of the injured workers die within 24 hours after injury, but the mechanisms of these treatments are unknown.
“The aim of our study was to identify the causes of death in injured individuals and the potential mechanisms involved in the detection and treatment of injuries,” said first author Eric, a researcher at the University of Lausanne and the University of Würzburg.・Dr. Frank said. , and his colleagues.
they discovered gram-negative bacteria Pseudomonas aeruginosa It caused a fatal infection in injured Matabele ant workers.
They showed that wound infections were associated with specific changes in the epidermal hydrocarbon profile, allowing nestmates to diagnose the infected status of the injured and apply appropriate antimicrobial treatment. .
They also identified 112 chemical compounds and 41 proteins in secretions from the ants' posterior thymus, half of which were found to have antibacterial or wound-healing properties.
“Chemical analysis showed that the hydrocarbon profile of the ant's epidermis changes as a result of wound infection,” Dr. Frank said.
“It is precisely this change that allows the ants to recognize and diagnose the infection status of injured nestmates.”
“For treatment, they apply antibacterial compounds and proteins to the infected wound. They ingest these antibiotics through the retropleura, which is located on the side of the thorax.”
“The secretion contains 112 components, half of which have antibacterial and wound healing effects.”
“And this treatment is highly effective, reducing the mortality rate of infected people by 90%.”
“Aside from humans, I don't know of any other creature capable of such sophisticated wound healing.”
“These findings have medical implications because the main pathogens in ant wounds are Pseudomonas aeruginosait is also a major cause of human infections, and some strains are resistant to antibiotics,” said the study's senior author, Dr. Laurent Keller from the University of Lausanne.
of result appear in the diary nature communications.
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ET Frank other. 2023. Targeted treatment of injured nestmates with antimicrobial compounds in an ant community. Nat Commune 14, 8446; doi: 10.1038/s41467-023-43885-w
Source: www.sci.news
