Fight Aging!

One approach to targeting cancer cells for destruction is to employ viruses as the kill mechanism, coupled with antibodies that can discern the type of cell to kill. The ideal outcome is that viruses infect only cancer cells, multiply inside them, destroy the cells and burst out to seek more victims, and then die out when there are no more cancer cells to target. There are, as always, challenges along the way to attaining this result, however:

Antibodies are proteins of the immune system that travel through the bloodstream and recognize potential threats to the body, whether bacteria, viruses or abnormal cells. Most antibodies have a characteristic Y shape. The tips of the Y form a "lock" that binds to a specific "key" carried by foreign bodies that the immune system should destroy. For decades, investigators have been putting human or mouse antibodies on viruses, and they haven't worked - the antibodies would lose their targeting ability. It was a technical problem. During replication, the virus is made in one part of the cell, and the antibody is made in another. To incorporate the two, the antibody is dragged through the internal fluid of the cell. This is a harsh environment for the antibodies, so they unfold and lose their targeting ability.

Now, scientists showed that unlike human antibodies or those of most other animals, the antibodies of camels and alpacas survive the harsh environment inside cells and retain the ability to seek out targets, potentially solving a longstanding problem in the field of gene therapy. The "lock" of camelid antibodies consists of the stem of the Y only, so it can't unfold in the harsh internal environment of the cell. The researchers used human cells grown in the lab for the study. They say it demonstrates the possibility of directly delivering genetically engineered viruses to specific cells. The goal is to infect only cancer cells and then trigger the virus to replicate until the cells burst, killing them and releasing more of the targeted viruses.

"We found that when we incorporated the camelid antibodies into the virus, they retained their binding specificity. This opens the door to targeting these antibodies to specific tumor markers. We want this new level of targeting specificity because it would allow us to inject the virus into the bloodstream, where it would exclusively infect and replicate in tumor cells, even if they are disseminated throughout the body. These viruses are already engineered to replicate only in tumors. These camelid antibodies would enable them to become even more tumor-specific and open the door for use in metastatic cancer."

Link: http://www.futurity.org/camel-antibodies-tumors-859932/