Hi, Sergio.
It's great to hear from you, and I'm so glad to hear how well you are doing!
As you know, I offer a lot of hypotheses.
Time will tell whether they are actually valid.
O.K., here's my hypothesis for GcMAF in ME/CFS, in the light of the GD-MCB hypothesis for the pathophysiology of this disorder:
A person who has ME/CFS has a dysfunctional immune system. I believe that this results from glutathione depletion and the vicious circle mechanism it causes (which includes a functional deficiency in B12, a partial block in the methylation cycle, and draining of folate from the cells).
This dysfunction includes low natural killer cell and low cytotoxic T-cell (CD8) activity as a result of inability of these cells to produce enough perforin and granzymes, which I have suggested results from glutathione depletion in these cells.
Because of this dysfunction, the immune system is not able to effectively deal with viral infections.
Another effect of the glutathione depletion is that the normally latent herpes family viruses are allowed to reactivate, because glycoprotein B is able to form disulfide bonds.
So now the viruses are reactivated, and the immune system's normally most effective antiviral responses are not functioning well.
The depletion of glutathione also causes a shift to the Th2 immune response, and this allows intracellular bacteria to go unchallenged, also.
The immune system is left with trying to fight these infections with antibodies and also with the RNase-L system, which is supposed to be a temporary response, but because the cell-mediated immune response does not rise up to take over the fight, it remains activated.
This constitutes a guerrilla war, with neither side winning. Some of the cytokines that are produced are proinflammatory, and this produces inflammation and oxidative stress, placing an ongoing demand on glutathione, thus helping to preserve the vicious circle mechanism that is at the core of the pathogenesis of ME/CFS.
O.K., that's the status of the immune system in the person who has ME/CFS.
Now, let's consider the GC protein:
The liver normally produces GC protein (also known as vitamin D binding protein) and exports it to the blood.
If an activated B cell and a T cell act on this protein with their respective membrane-mounted enzymes, they convert it to GcMAF
GcMAF activates the macrophages.
The activated macrophages express a variety of receptors that recognize virions, and they thus engulf and kill any of them they find outside of cells.
The activated macrophages also kill intracellular bacteria that are in vesicles inside them.
Certain viruses produce nagalase, which prevents the normal conversion of the Gc protein to
GcMAF, thus preventing the macrophages from activating.
Treating a person with exogenously prepared GcMAF overcomes the nagalase inhibition, and activates the macrophages, so that they can kill viruses and intracellular bacteria.
When these pathogens have been killed, the immune system stops the production of proinflammatory cytokines, and the inflammation decreases.
This decreases the oxidative stress, and this takes demand off glutathione, which allows it to rise.
The more glutathione rises, the more the symptoms decrease.
If glutathione is able to come up far enough, and a high enough ratio of reduced to oxidized glutathione can be achieved, there is hope that the vicious circle mechanism can be broken, and the person can recover.
The Rituximab treatment was apparently able to achieve this in some of the patients treated. In those cases, I suggest that knocking out the B cells caused enough of a decrease in the inflammation that glutathione was able to recover enough to correct the vicious circle mechanism and the immune dysfunction, so that when the B cell population came back up, there was no longer a Th2 shift. Perhaps this also knocked out viruses such as EBV that reside inside B cells, as Nancy Klimas has suggested.
Let me know what you think about this.
Best regards,
Rich