The ability to program living cells to behave in certain ways in certain conditions can create a new condition in medicine.
In a study, researchers programmed bacteria in mouse to fight cancer. Some tumor spread and bloom because they send a signal to the immune system to leave them alone. Tumors that don’t send signals are vulnerable and the immune system can digest them.
But now Columbia University in the city of New York has shown that it is possible to program bacteria that can switch off the “don’t eat me signals” so the immune system can easily attack them.
It is the example of synthetic biology, in which medical treatments promise to be very effective than any other molecular method.
In recent medicine paper, researchers describe how they programmed bacteria for a specific purpose and shrank tumors and increase the survival rate of mouse.
In addition to this they also saw that untreated tumors, nad secondary tumors also responded to this.
Sco-senior author state that “ we witness the first demonstration of an abscopal effect in cancer treatment in which bacteria uses”.
The abscopal effect is the ability to induce antitumor response that destroy cancer cells which are far away from the primary target.
Cells that sends don’t eat me signals are also common in healthy cells. So it is a challenge to immunotherapies that target the signals.
Researchers try to overcome this challenge by programming the bacteria so they can release signal silencing-payload when they send the “tumor microenvironment”.
This payload itself was an encoded nanobody and non-pathogenic Escherichia coli strain.
However, these payload left enough bacteria to startnew population, that can be used in repeating cycle of drug delivery in the tumors.
Researcher has demonstrated that these type drug delivery strategy worked before by targeting CD47 protein.
It doers two things first, bacteria cause local inflammation in the tumors. This calls immune system. Second thing trigger immune cells to ingest the tumors cells because it switches don’t eat me signals.
This results, first immune system target primes “tumor-infiltrating T cells” and then migrate to distant metastases.
This method may be safe and induce anti-tumor immunity by adding local delivery of immunotherapeutic payloads. They already tested this methode for other types of cancers in mice.
After that they hope to proceed to clinical trials in human.
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