Rheumatoid arthritis and the immune system

 Hi, I'm confused about recommendations I'm seeing on various alternative medicine and nutrition sites that recommend things as being beneficial for rheumatoid arthritis because they are immune system boosters. This does not make sense to me; the conventional "wisdom" is that the immune system should not be boosted in an auto-immune disease as boosting would just make it do more damage.  Can you shed any light on this? 

More generally, is there evidence for any successful way of "retraining" the immune system to keep it from attacking the body's own tissues? (in auto-immune diseases generally and rheumatoid arthritis in particular)