Major basic protein and topical administration of ketotifen in pollinosis under natural allergen provocation

In this study we investigated the potential relation among subjective symptoms, blood eosinophil counts and the levels of major basic protein (MBP) in serum throughout the pre- to postpollen season. In addition, we compared the effects of topical administration of ketotifen on these parameters between the prophylactic treatment group (n = 10) and the postsymptomatic treatment group (n = 10). We found that (1) the levels of MBP in serum during the season were significantly higher than those before the season and (2) the levels of the above three parameters in the prophylactic treatment group were significantly lower than those in the postsymptomatic treatment group during the season. It was concluded from these results that the action of MBP may be involved in the pathogenesis of allergic rhinitis. Furthermore, for the first time we provided evidence that topical ketotifen administration could suppress the systemic upregulation of the blood eosinophil count and MBP level in subjects with pollinosis.