Toxoplasma gondii binds sheep prolactin.

Taking into account the literature reports on the involvement of prolactin (PRL) in the regulation of immunity against Toxoplasma gondii, we decided to check whether this parasite has the ability to bind the lactotrophic hormone. We examined T. gondii binding of sheep fluoresceine- and biotine-labeled prolactin isolated from pituitary (shPRL). In this work we announced for the first time that shPRL was bound to live tachyzoites of RH (type I) and ME49 (type II) strains. Furthermore, by use of competitive inhibition analysis, we confirmed that this binding was specific for both tested T. gondii strains.