Humoral response of captive zebra sharks Stegostoma fasciatum to salivary gland proteins of the leech Branchellion torpedinis

► Captive zebra shark humoral immune response to Branchellion torpedinis salivary gland proteins was examined by ELISA and Western blot. ► High salivary gland-specific IgM serum titers were demonstrated by ELISA in B. torpedinis infected zebra sharks. ► IgM targeted specific salivary gland proteins including an ADAMTS family protein, tubulin, aldehyde dehydrogenase, and unidentified proteins. ► Humoral immune response warrants further investigation as there may be options to exploit immune mechanisms to reduce leech burdens in aquaria.