The blood cells are returned to the patient so that while the cell profile does not change, the circulating blood proteins are diluted, including cytokines, autoreactive antibodies or toxins, and such pathogenic determinants of specific disorders.

Although its full therapeutic benefits are still being discovered, TPE is one of the treatments for autoimmune and neurological diseases

Even just cleaning up glycolipids may partially “reboot” immune system.

First of all, they are part of immune response regulation.

Second of all, they are the reason #1 why cancer often leads to immune problems.

Many forms of tumors make the rapidly growing cells shed membrane glycolipids, and since NKT already monitor very similar compounds, the adaptation is that they actively track down and destroy the sources of shedding. This allows rapid response, there’s not even a significant tumor as such yet. The flip side is that when this process lags too much (the obvious possibilities are T-killers being already exhausted by something else, or there are simply too few due to recent blood loss or poisoning), the growth sheds more and more glycolipids, and then immune system gets continuously jammed by the “smell” too widespread to track the gradients properly.

So, remove glycolipids from bloodstream, but keep cells, add some ready wake-up signal (like ?-GalCer https://www.nature.com/articles/s41467-021-21480-1), and it will be “Round 2″. May need several iterations, of course.