Let me preface this article by saying I am not a medical expert of any sort. I recently saw an interesting article claiming Polysaccharide K could inhibit or reverse several kinds of cancer. I looked briefly into the academic literature on this, which was confirmatory, and while trying to understand the immune response to this compound I hypothesized it might help out in MS prevention. I found an article which might add weight to that theory. The intended output of this article is not to argue that there is a research need with respect to further investigation of the effect of Polysaccharide K on MS.
Articles confirming Polysaccharide K, also known as OK-432 as anticarcinogenic:
The third article gives a good reason to hypothesize polysaccharide K as beneficial for MS. How does polysaccharide K provide a boost to the immune system? In the third article, Maehara et al state that they know of some “antitumor immune responses including maturation of dendritic cells, correction of Th1/Th2 imbalance, and promotion of interleukin-15 production by monocytes”
It’s the T helper cells which link this as a potential MS antipathogen. In a 2005 paper from Lull et al, we read:
Many diseases such as leprosy, allergy, multiple sclerosis, and responses to immunotoxic agents have pathology associated with aberrant TH1 and TH2 polarization.
The Lull paper mentions polysaccharide K directly, but doesn’t point to the immunomodulating property of that compound. Instead they just note that it “might be associated” with dendritic cell maturation, which has elsewhere been well established, but would only constitute a nonspecific response to MS. The Lull paper also discusses other polysaccharides other than polysaccharide K, and they suggest that a multi-polysaccharide approach, or perhaps even a whole-food approach using certain mushrooms, could be a comparatively strong treatment to isolating a single polysaccharide:
There are several reports of mushrooms containing more than one polysaccharide with antitumor activity. The responses to different polysaccharides are likely to be mediated by different cell surface receptors, which may be present only on specific subsets of cells and may trigger distinct downstream responses. A combination of such responses involving different cell subsets could conceivably provide greater tumor inhibition than could be induced by a single polysaccharide .
I appreciate the whole food theory and I think it’s worth research as an MS treatment as well, but it seems relatively indirect, and therefore non-potent in expectation, for the specific treatment of T cell imbalance.
I have established that polysaccharide K, known as an anticarcinogen, is also a candidate treatment for multiple sclerosis, but it’s not yet medically recognized in the USA and in Japan it’s prescribed for cancer, so how does one go about obtaining polysaccharide K? As far as I’m aware, it’s not available anywhere over the counter. I don’t know about Japanese medical law. Maybe you could talk a doctor into prescribing it even though MS is not the typical use case. Finally, you could wait for a research trial to happen and then enroll in that.
The good news is that polysaccharide K seems to have low side effects, so even if the benefit is small, the health-cost, as opposed to the financial cost, also seems small and low risk.
Getting polysaccharide K directly doesn’t seem super workable, but this compound is extracted from a certain mushroom, and we earlier said there is some reason to think that ingesting the mushroom directly might be helpful, if to a lesser degree than the isolate. Here we find more good news:
Polysaccharide K, also known as PSK or by the trade name Krestin, comes from the mycelium varieties Trametes versicolor (also known as Coriolus versicolor or turkey tail mushroom).
Googling around for some of the above terms indicates that the mushrooms is legal, cheap, and plentiful. Walmart cells a bottle of 120 capsules of 1000mg each for about $20 on the cheaper end. On the more expensive side, Pine Street Clinic cells a 120 capsule bottle for $70, and notes that their product is made of biomass, not just extract. They state:
Coriolus versicolor can generally be used in two forms: extract and biomass. Most Corioluson the market is an extract, but current science increasingly suggests that biomass is superior because it also incorporates important immune-enhancing enzyme activity, such as superoxide dismutase, peroxidase, glucoamylase, and protease activities, which are not detected in the extracted forms of mushrooms.
This Coriolus mushroom powder is from mycelial biomass.
In conclusion, polysaccharide K, and perhaps some other fungal polysaccharides, should be further explored for MS suitability, but interested patients may go ahead and try the less potent whole-food approach by ingesting turkey tail mushrooms directly, legally, cheaply, and with low risk and low magnitude of expected side effect.