IL10 and helminthiasis: For example, it has been found, that in certain populations where helminth infections are prevalent, a positive skin prick test for environmental allergens, such as house dust mites, (HDM) shows that they are reduced [3,4], which could be explained by IL-10 production [5] and the effects of immunomodulatory components [6], among them cystatins of the family of cysteine pro-tease inhibitors (CPIs) [7,8,9,10] that interfere with antigen processing via MHC class II molecules [11,12,13,14].