Take a look at this link and see if you think it would be beneficial to explore.
http://seandennis.com/nac4mds/index.html
I too don't think you want to "stimulate" the immune systems, instead you are looking to restore balance to it by reducing inflammation which can overstimulate some aspects of your system. The way I see it, mainstream & alternative medicine focuses on two approaches to blood/BM disorders. One is on inflammatory process and trying to regulate it. The other is on gene expression. Turning on or off the gene's that are responsible for the condition. I know I'm not expressing myself very well here because it is so complex and I haven't been able to fully understand and articulate all that I've been reading lately. But antioxidants play a big role in reducing inflammation and B vitamins play a big role in proper gene expression as well as keeping DNA/RNA healthy. On gene therapy, they feel that it's not the gene but the environment that it's in which is turning a bad gene on or turning a good gene off. This is my current thinking right now...don't know if it's right or not but I think its directionally correct.
We have focused on correcting nutritional deficiencies for John and are seeing positive improvements in his counts. He does not have MDS though but these diseases are so closely related.
Hope this helps....keep reading all you can.