We’ve all heard about the growing threat of multi-drug resistant bacteria, or so-called “superbugs” – and it’s pretty scary. These pathogenic (disease-causing) bacteria cause serious and sometimes deadly infections and they can become resistant to even antibiotics of ‘last resort’.

One of these pathogenic bacteria is methicillin-resistant Staphylococcus aureus or MRSA for short. MRSA can cause serious and sometimes fatal bloodstream or tissue infections, often when someone is in the hospital.

In a paper published in Nature, Genentech scientists answer a nagging question about treating MRSA infections - namely why are these infections so hard to treat, even when the bacteria are sensitive to the antibiotics?

It’s long been suspected that a small number of MRSA hides in a compartment of our own immune cells protected from antibiotics. The bacteria then use our own immune system as a “Trojan horse” to spread the infection after the course of antibiotics is over. The Nature paper finally proves this long-standing theory with elegant science. Importantly, the paper also describes a way to take advantage of this phenomenon to strike MRSA where it hides.

Inspired by work in oncology, the team developed a first-in-class antibody drug platform to deliver a potent antibiotic inside the human immune cell. In principle this approach could be applied to combat a variety of pathogens in addition to MRSA.

To learn more, watch the video and read the paper from Genentech scientists below.

Nature. Novel antibody–antibiotic conjugate eliminates intracellular S. aureus