Prevention of aggregation in treatment of Staphylococcus aureus infections



Infections with Staphylococcus aureus are causing life-threatening diseases in hospitals worldwide (1-4). Data from the USA show that about 1% of hospitalized patients acquire infections with S. aureus. Of these, about 10% are fatal resulting in 12,000 deaths and $9.5 billion in excess costs, annually (5, 6). S. aureus has an ability to cause persistent infections, which even for strains that are not multidrug-resistant, can be hard to eradicate with antibiotic therapy.

One reason for persistent infections is S. aureus’ ability to establish itself in sessile densely packed communities known as biofilms on natural body surfaces as well as medical implants (7, 8). In contrast to multidrug-resistant S. aureus strains (MRSA), which can still be treated with some antibiotics (9), all S. aureus strains become highly resistant to antibiotics just by living in biofilms (10). However, cells in a biofilm are per definition sessile and if they detach from the biofilm to spread, they become vulnerable to antibiotics as well as immune defenses (11-13). Some pathogens have circumvented this problem by assembling into large mobile multi-cellular units (aggregates) which opposed to biofilms are not attached to a surface (12, 14-17). In addition to being mobile, aggregates possess the same protective properties as biofilms (12, 17) and has been shown to be essential for adherence to host cells, phagocytosis resistance and virulence in mice (16). Furthermore, aggregation is induced in clinical settings (18, 19) and may thus be a hitherto overlooked condition with serious clinical consequences such as embolism (1-4).


Reference List


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Contact PASTI: Jakob Haaber - Dep.Veterinary Disease Biology - University of Copenhagen - Stigboejlen 4 - 1870 Frederiksberg C -