Moraxella catarrhalis is only a weak activator of the mannose-binding lectin (MBL) pathway of complement activation


  • Edited by M. Mitsuyama

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A hemolytic bystander assay was used to assess the functional serum mannose-binding lectin (MBL) activating capacity of five isolates of Moraxella catarrhalis obtained from children who suffered recurrent acute otitis media episodes. Results showed that this organism is only a poor activator of the lectin pathway of complement activation, with subsequent consequences for the etiology of otitis media by this organism.