Vaccinia viruses are therapeutic tools with different biomedical applications depending on susceptibility characteristics. For example, the strain called MVA (modified vaccinia Ankara), which cannot replicate in mammalian cells, triggers a powerful immune system response and is used to develop vaccines against COVID-19 or AIDS. On the contrary, other strains such as Western Reserve (WR) or Copenhagen (Cop), which replicate efficiently in tumor cells, are used to develop cancer treatments. For this reason they are called immuno-oncolytic viruses and are the basis of viral immunotherapy.
However, these viral strains have reduced immunogenicity, making them less effective in activating patients’ immune responses against tumors.
Now, a study led by the University of Barcelona, the Bellvitge Biomedical Research Institute (IBIDELL) and the University of Munich (Germany) has developed a new strain of vaccinia virus, which can replicate in tumor cells while maintaining greater immunogenicity. . Specifically, it can induce the so-called immunogenic cell death in tumor cells.
The study, published in the journal Molecular therapy, has been carried out with the support of the Spanish Association Against Cancer (AECC) and the collaboration of the State Research Agency (AEI). The new therapeutic tool, which has been tested in a wide variety of mouse models, has been shown to have reduced toxicity and a high capacity and efficiency to activate immune responses against tumors. The virus is also effective in different cancer treatments, such as melanoma, colon cancer and kidney cancer.
“In addition, we very significantly achieved the total disappearance of the tumors when we administered the virus repeatedly,” says expert Juan J. Rojas, first author of the study and principal investigator of the Faculty’s Immunity, Inflammation and Cancer group. of Medicine and Health Sciences of the UB and IBIDELL.
The discovery of this new viral strain represents a significant advance in viral immunotherapy research and demonstrates its therapeutic potential for the treatment of cancer patients.