Apelin is found in human sperm and testis and is raised in inflammatory pathological conditions.
Moretti E, Signorini C, Corsaro R, Noto D, AntonioTripodi S, Menchiari A, Micheli L, Ponchia R, Collodel G. Cytokine. 2023 Sep; 169:156281. Epub 2023 Jun 21.