Immunology

Breakthrough MRC-funded study from University of Leicester shows low dose injections of artificial properdin provides substantial protection against septic diseases in mice

• Artificial protein is found to strengthen the immune system
• It fights meningitis and septicaemia when given before or after infection
• Discovery opens up new avenues for fighting infections
• It is shown to be 100 times more efficient in fighting infection than the naturally occurring protein in our immune system
• Discovery has been patented and will be made available for clinical trials

"I am really excited about this landmark discovery. We demonstrate that boosting the innate immune system can have a significant impact on the body's ability to defend itself against life-threatening infections" -  Professor Wilhelm Schwaeble from the University of Leicester's Department of Infection, Immunity and Inflammation

Researchers at the University of Leicester have produced an artificial version of a naturally occurring protein, properdin, which has been found to successfully combat bacterial pneumonia and meningitis when tested in mice.

In the new study, published today (24 March) in the online early edition of the journal  Proceedings of the National Academy of Sciences (PNAS), the researchers have shown that a booster of the innate immune defence has a profound and immediate effect on the body's ability to clear infections, even when the bacteria have reached the bloodstream.

The study, funded by the Medical Research Council (MRC), found artificially produced properdin (P_n) to be 100 times more efficient at fighting infection than naturally occurring properdin, offering significant protection in mice against Streptococcus pneumoniae and Neisseria meningitidis infections.

Streptococcus pneumoniae is the leading cause of pneumonia and a major cause of septicaemia and meningitis, responsible for approximately 1.2 million deaths per year globally. Neisseria meningitidis causes epidemic bacterial meningitis and septicaemia with a high mortality in children and young adults.

Research lead Professor Wilhelm Schwaeble, Professor of Immunology and Royal Society-Wolfson Research Merit Award Holder from the University of Leicester, explained: "I am really excited about this landmark discovery. We demonstrate that boosting the innate immune system can have a significant impact on the body's ability to defend itself against life-threatening infections."

An additional benefit of this treatment is that it was shown to effectively neutralise the harmful toxins released by bacteria when they are destroyed. There is a recognised problem with current treatments which can kill bacteria but do not combat the effects of toxic substances inside or released from bacteria, which often prove more harmful than the bacteria itself.

The artificial properdin was shown to kill bacteria by making them 'pop' like balloons in mouse and human blood with massive numbers of meningitis bacteria being directly destroyed following P_n treatment. This method was also tested by the researchers on human blood in the lab where it was found to have a similar combative effect.