- The Ov20 protein of the parasitic nematode Onchocerca volvulus. A structurally novel class of small helix-rich retinol-binding proteins. Kennedy, M.W., Garside, L.H., Goodrick, L.E., McDermott, L., Brass, A., Price, N.C., Kelly, S.M., Cooper, A., Bradley, J.E. J. Biol. Chem. (1997)