DHRS2 and otitis media: Recently, antigenic responses to several of the promising candidates have been measured for otitis-media-prone children and their controls; these include the recombinant soluble PilA (rsPilA) fused with protein E, protein D and the ubiquitous surface protein A2 (UspA2) from Moraxella catarrhalis, as well as ChimV4 (a chimera of protective epitopes from rsPilA) and the outer membrane protein P5 (OMP P5)35.