Topical immunoglobulin is an effective therapy for parainfluenza type 3 in a cotton rat model.

Abstract

A cotton rat model was used to test the efficacy of topical immunotherapy against parainfluenza type 3 (PIV3) infection. On day 3 after experimental infection with 10(5.5) pfu of PIV3, animals were treated with 2-fold dilutions of convalescent cotton rat serum or with one of two purified human immunoglobulin preparations; all three had moderate titers of anti-PIV3 neutralizing antibody (range, 1:200-1:1000). Therapy with high concentrations of all three preparations resulted in significant reductions of > or = 2 logs (> or = 100-fold) of pulmonary virus titers compared with titers for control animals. Little or no reduction in virus titers were seen in nasal tissues.