Replies to post #249842 on Biotech Values

[Biowatch]

As with all gene therapy products with integrating vectors (lentiviral or retroviral vectors), the potential risk of developing secondary malignancies is labeled as a class warning in the U.S. prescribing information (USPIs) for approved BCMA-directed and CD19-directed genetically modified autologous T cell immunotherapies.

This doesn’t seem to involve CRISPR. Retroviral vectors tend to integrate near oncogenes already present in the genome, i.e., your DNA, increasing the odds of triggering an oncology/cancer event.

It was my understanding that lentivirus vectors integrated in a more random fashion, reducing the chance of activating an oncogene.

https://en.wikipedia.org/wiki/Lentivirus

HIV is a lentivirus, and using that as a viral vector makes it more efficient at introducing the desired chimeric gene into a T cell. Both types of viral vectors have been heavily modified to make sure that they can’t replicate nor spread nor resemble the nastier aspects of their parent virus.

P.S., “Integrating vectors” means that it inserts itself into the DNA/chromosome of the recipient cell, so will be there for the life of that particular cell. There are some viral vectors that merely enter the cytoplasm of a cell and produce proteins from there, but they usually don’t last as long in terms of providing a therapeutic effect.

Even viral vectors that integrate into the DNA of the cell can be shut down and not last forever, by methylation or whatever, Plus, T cells don’t last forever, so even ones that incorporated the chimeric gene may fade away and disappear.

P.P.S. Beware of adding a start codon in front of a gene you want to remain silent.