ABSTRACT
The bindings of 125I-laminin to trypomastigotes is specific and 2-5 x 10**3 laminin-binding sites were calculated to be presented on the surface of a live trypomastigote. Anti-laminin antibodies were able to inhibit the invasion of cultured cells by trypomastigotes (62-75 per cent), suggesting that laminin may be involved in the adhesion of the parasite to host cells. By affinity chromatography, an 85-KDa glycoprotein was isolated (laminin-bindign glycoprotein, LBG) from trypomastigote lysates, but not from epimastigote lysates. It is suggested that at least fragment E8 (but not E1) from laminin could be involbed in the reaction which is independent of the carbohydrate moieties from both ligand and recepto. It is also shown that LBG is member of the Tc-85 family, previously shown to be related to the invasion process of the parasite