Blood clotting factors may help fight superbugs, research suggests

The processes that help wounds heal after injuries may be able to help in the fight against superbugs.

Coagulation factors which are involved in blood clotting could potentially offer new strategies for combating multi-drug resistant bacteria, scientists say.

Infections caused by these bacteria pose an urgent public risk as there is a lack of effective drugs to tackle them, the study published in Cell Research sets out.

A deficiency in coagulation factors – like in haemophilia patients – has been associated with diseases such as sepsis and pneumonia.

Researchers say this has led to the suggestion these factors may also have a role in anti-infection mechanisms.

Scientists at Sichuan University, China, say the factors VII, IX, and X – which are well known for their roles in blood coagulation – may act against Gram-negative bacteria.

Extensively drug-resistant pathogens such as Pseudomonas aeruginosa and Acetinobacter baumannii are included in this.

Both bacteria were recently listed by the World Health Organisation among 12 bacteria that pose the greatest threat to human health because of their antibiotic resistance.

Gram-negative bacteria are characterised by their cell envelopes, which are composed of an inner cell membrane, a thin cell wall and an outer membrane that make them harder to kill.

Corresponding author Xu Song, said: “In our study, we report a class of human antimicrobial proteins effective against some drug-resistant ‘superbugs’.

“Unlike many antibacterial agents that target the cell metabolism or cytoplasmic membrane, these proteins act by breaking down the lipopolysaccharides of the bacterial outer membrane through hydrolysis.

“Lipopolysaccharides are crucial for the survival of Gram-negative bacteria.”

The study suggests that coagulation factors act on the bacteria via light chains – one of two domains of the proteins.

In cells in the laboratory, the authors showed that treatment of cells of the bacteria E. coli with light chains led to clearly observable damage to the bacterial cell envelope initially.

They observed almost complete destruction of the cell within four hours.

The light chain of coagulation factor VII was effective against all Gram-negative bacterial cells tested.

The research suggested light chains, as well as the coagulation factors as a whole, were also effective in combating Pseudomonas aeruginosa and Acinetobacter baumannii infections in mice.

Heavy chains had no effect.