A door to immunotherapy

A team of researchers from the Spanish Center for Cardiovascular Research has described a cell signal that hinders intercellular communication and may be key to biomedical strategies such as gene therapy, vaccine design or immunotherapy.

In particular, the study published in the journal Nature Communications shows a cellular signal that prevents the secretion of nano vesicles, called exosomes, that are secreted outside by the cells to communicate with each other. However, they can sometimes be used as “trojan horses” by certain viruses to facilitate their propagation and entry into neighboring cells.

The researchers explain that the signal, called ISGylation, has been described primarily as an antiviral signal, although some studies have shown that it can also be activated against other stimuli such as lack of oxygen, aging or cancer. In these contexts the secretion of exosomes and, therefore, the communication between cells, could be affected as a result of this modification.

In their work the researchers describe how an antiviral signal activates a protein degradation protocol involved in the production of exosomes. This signal marks the specific proteins that reside in the endosomes, the site of formation of the exosomes, so that they are redirected towards the path of degradation and the secretion of nanovesículas is prevented. This is a new mechanism by which cells defend themselves against infection by activating the degradation of their own proteins, but it also can be used by the external agent for its propagation.

On the other hand, researchers know that deciphering the processes that control the secretion of exosomes is fundamental for its biomedical application because in addition to acting as messengers in intercellular communication, exosomes are potential tools for gene therapy, vaccines and immunotherapy. In fact, there are currently numerous clinical trials for the development of new treatments using this knowledge.