BERLIN - A recently identified protein of viral origin could become a new weapon against pneumonia, according to data from a recent animal study.
The protein, Cpl-1, is derived from bacteriophages -viruses that attack bacteria-, and specifically attacks pneumococci.

With pneumococcal resistance to multiple antibiotics on the rise, treating community-acquired pneumonia has become a challenge. Streptococcus pneumoniae is still the predominant pathogen in this disease, write Dr Martin Witzenrath and colleagues from Universitätsmedizin Berlin, Germany, in the journal of Critical Care Medicine.

When the researchers treated mice infected with pneumococci 24 or 48 hours after infection, the phage protein achieved comparable cure-rates to an antibiotic (amoxicillin). In contrast, untreated mice succumbed to their pneumonia.

All the mice were suffering from severe pneumonia at the start of therapy. When treatment began after 24 hours, all Cpl-1-treated and most amoxicillin-treated mice survived and showed rapid recovery. When treatment was not started until 48 hours after infection, the mice had developed bacteraemia, and only three of seven Cpl-1-treated and five of seven amoxicillin-treated animals survived emphasising the need for prompt therapy, whatever treatment is used.

Bacteriophages are viruses that enter bacteria, replicate and destroy their hosts upon leaving. The concept of using bacteriophages to kill bacteria has been known for many years in medicine. In the case of the bacterial enzyme Cpl-1, the advantage could lie in its specificity for the common pneumonia pathogen.

“Cpl-1 may provide a new therapeutic option in the treatment of pneumococcal pneumonia,” concludes Dr Witzenrath.