Tricking the immune system to fight germs
A new substance could help fight malicious infections. The substance activates the endogenous defence.
Antibiotics do not differentiate between „good“ and „bad“ bacteria – between those that sicken people and those that are good for humans. Antibiotics destroy them all. They destroy, therefore, also vital bacteria in the bowel that enable digestion, produce vitamins and protect against infections.
Anyone who swallows antibiotics hence alters his intestinal flora. This can lead to easier distribution of germs in the bowel. One example is enterococcus bacteria which infect the blood through the bowel if they occur in high concentrations. Especially for patients who are already weakened they can become particularly dangerous as they can trigger blood poisoning.
There are strains of enterococcus called VREs which are resistant against the antibiotic Vancomycin. VREs are dreaded germs in hospitals. If they infest a patient who has just had an organ transplant this can be life-threatening.
How can we stop VREs?
Doctors can try to save the patient with the help of emergency antibiotics. A new method that is still in the experimental stage is the so-called faecal transplantation. In order to restore balance among bacteria the faeces of a healthy person is inserted rectally to the bowel of the sick person. However, inserting external faeces remains little studied and might hold dangerous side effects.
Scientists led by Michael Abt from New York’s „Memorial Sloan Kettering Cancer Center“ have now tried out a different strategy: They infested mice with the dangerous hospital germ VRE. At the same time they infested the mice with noro viruses. They are particularly dreaded in schools, kindergartens and retirement homes as they are easily transferred. In addition, they cause severe diarrhoea and vomiting.
However, the double infection has a totally different effect: the mice recover faster. The noro virus helped to contain the infection. The reason: The immune system was additionally activated with the help of the virus.
A similar effect occurred when the scientists gave them Resiquimod which is an experimental drug against herpes. It pretends that a virus has entered the body. The immune system is activated and reacts.
Like other new methods, this method has to be further explored. In case the immune system is overactivated, severe side effects might occur.
