New Method to Inhibit Biofilm Growth on Medical Implants

Researchers from Sahlgrenska Academy have developed a new technique to prevent biofilm formation. Coating implants and catheters with “tissue plasminogen activator” prevents the infectious agent Staphylococcus aureus from colonizing their surfaces. The study has been published in the journal Applied and Environmental Microbiology.

Biofilms are groups of microorganisms that occupy a surface and are connected to each other through an extracellular polymeric substance secreted by the cells. The microorganisms and the slime form a matrix that adheres to a living or non-living surface, and can cause serious infections and transplant failure when they colonize medical material.

Staphylococcus aureus is one of the more common biofilm-forming microorganisms. In previous studies, Professor Jin discovered that S. aureus recruits the human clot formation machinery to create a frame where the biofilm anchors. Jin speculated that eliminating the small clots would prevent the biofilm from forming properly.

A clot-dissolving protein to eliminate biofilm

Professor Jin’s team applied the tissue plasminogen activator (tPA) to mice implant surfaces and to microplates. tPA catalyzes the conversion of plasminogen to plasmin, a blood enzyme that dissolves clots by degrading fibrins in a process known as fibrinolysis. As expected, tPA-treated surfaces inhibited biofilm formation by different S. aureus strains, both in vivo and in vitro. tPA also increased biofilm sensitivity to antibiotics.

Many different microorganisms can form biofilms, but the authors think that their technique could be successfully applied to any of them. It is estimated that more than 60% of bacterial infections are caused by biofilms, and the number is expected to grow due to the increasing use of medical implants and prostheses. This study could help to prevent hospital acquired infections and the associated deaths.

Source: Sahlgrenska Academy