Eosinophils normally make up approximately 1 to 3 percent of the white blood cells in the peripheral blood. With allergies this percentage increases. When steroids are administered the typical amount of eosinophils will decrease. They serve various functions in the body including, antiparasitic and antibacterial activities, participation in the allergic response, and modulating inflammatory responses.

PPA's Human Normal Peripheral Blood Eosinophils are isolated from peripheral blood granulocytes by indirect immunomagnetic selection. All peripheral blood is collected from fully consented IRB approved donors that test negative for HIV, HBV, and HCV.