Differences in the composition of inflammatory cell infiltrate in lens-induced uveitis under therapy with allopurinol or steroids

The aim of this study was to compare the qualitative changes in the composition of inflammatory cell infiltrate in lens-induced uveitis (LIU) under treatment with allopurinol (Allo), methylprednisolone (Pred) or the two drugs combined (Allo/Pred). Twenty male Wistar rats were sensitized with lens proteins for eight weeks. Intravenous (IV) therapy was started after anterior capsule disruption in one eye of each animal. Five rats were randomly assigned to each of the four groups: controls, Allo (50 mg/kg bw), Pred (7.5 mg/kg bw) and Allo/Pred (50 mg/7.5 mg per kg bw). Eyes were enucleated 24 hours later and fixed in paraformaldehyde/glutaraldehyde. Sections at three levels were stained with Giemsa and examined using a 0 to 4+ score for each type of inflammatory cell. Granulocytes were seen as neutrophils and eosinophils. Neutrophils were divided into polymorphs and "others", and graded with lymphocytes. In all therapy groups there was a significant reduction of polymorphs (p