OGG1 and colitis: However, while tissue eosinophilia is commonly observed in inflammatory bowel disease and colon inflammation, the role of IL-5 in mediating intestinal pathology is not clear.[76] A recent study indicated that tissue eosinophils may serve to protect against tissue injury in DSS-induced colitis.[110] Our observation of a remarkable increase in serum IL-5 levels in Ogg1-/- mice (Fig 6E) may thus correspond with the severity of inflammation in Ogg1-/- animals and may signal a compensatory response to tissue injury in these mice.