Why hydroxychloroquine is effective in treating systemic lupus erythematosus?

It is magic?: 1the use of anti-malarials in autoimmune diseases was accidentally discovered in treating wwii vets for malaria. Those with RA improved. Chloroquine and ho-q were tested in sle, with very positive results. In the early 80's canadian researchers definitively showed fewer sle flares with ho-q. It is considered the rx of first choice for :sle. We now understand more of the mechanisms, but not all.