Detection of bovine lactoferrin binding protein on Jurkat human lymphoblastic T cell line.

Lactoferrin (Lf), a member of the transferrin family protein, is an iron-binding protein that is known to interact with mammalian cells through a specific receptor. We examined binding of Lf to Jurkat human lymphoblastic T cell line (Jurkat cells) by far Western blotting, and found that bovine Lf and human Lf bound to the same protein components of Jurkat cells, and that pepsin digestion of Lf disrupts the sites responsible for binding to cellular proteins. We also found that the sugar chains of bovine Lf are not involved in binding between bovine Lf and Jurkat cells. Bovine Lf, bovine transferrin and ovotransferrin bound to the same proteins of Jurkat cells, which had molecular weights of about 35 kDa.