Control of CAR-T immune cells could mean safer, more precise cancer treatment for CLL and many other cancers.

[AussieNeil]

'Researchers at the University of California-San Francisco have engineered a molecular "on switch" that allows tight control over the actions of immune cells known as T cells, according to new research published in Science Express:"

medicalnewstoday.com/articl...

The linked article above (posted to the CLL Groups.io forum - thanks Linda!), provides an easily readable overview of CAR-T therapy, which was initially successfully trialled on CLL patients.

In addition to the very high cost of providing CAR-T therapy, where an individual's T-cells are engineered to seek out and kill cancer cells (with the process already proven effective for CLL patients), there's the problem of stopping the CAR-T cells when they have brought the cancer under control. CLL patients already successfully treated with CAR-T therapy need to be on expensive IVIG transfusions for the rest of their lives unless the CAR-T cells can be switched off, because just like other CLL treatments, the CAR-T cells kill all B-lymphocytes, whether or not they are cancerous CLL cells. Normally, B-lymphocytes become keyed to a particular pathogen, then mature into plasma cells (antibody factories) or memory B-lymphocytes (so the next time you are exposed to the same pathogen, your body can rapidly ramp up production of antibodies to kill off the pathogen). Since CAR-T treated CLL patients can't produce antibodies, as they are no longer able to make plasma cells, they need 'antibody transplants, i.e. IVIG indefinitely, where each transfusion comes from the pooled donations of thousands of blood donors - hence its expense.

Achieving this on-off switch breakthrough was a natural extension of the CAR-T therapy, given the above issue, so it is very encouraging to see that researchers have achieved this next developmental step. While the article emphasises the benefit of being able to control the timing and degree of CAR-T activity to work in with concurrent CLL treatment, theoretically, treated patients could have their CAR-T cells turned off once they'd reached remission, then turned back on again if their remission ended.

Exciting news!

Neil

[Justasheet1]

Neil,

Great article. I didn't know about some of the side effects of Car-T. Apparently the drug they are using now to switch the therapy on and off is not the one that's needed for humans but proves their experiment. They are on the right track and there's big money behind this.

Jeff

[DebinOzinLondon]

Wow very exciting - I've been asked to speak at an experimental medicines conference at Barts on Thursday to give a patient perspective on entering clinical trials to scientists, researchers and Drs attending - it is amazing the work they're all doing on our behalf - I will make sure I end the speech by telling them how incredibly grateful we are for all those long hours in the lab and how much hope they're giving those of us who have an incurable disease (not for much longer I hope!). Thanks for posting.

[wroxham-gb in reply to DebinOzinLondon]

Good luck with the speech on Thursday deb. You'll do well, and I think they will enjoy hearing from a patient.

Sue

[Peggy4 in reply to DebinOzinLondon]

Good for you! Peggy

[wroxham-gb]

Thanks for this Neil. Hope!

Sue

[Peggy4]

Exciting indeed. Thanks Neil