Trypanosoma cruzi binds to laminin in a carbohydrate-independent way.
The binding of 125I-laminin to trypomastigotes is specific and 2-5 x 10(3) laminin-binding sites were calculated to be present on the surface of a live trypomastigote. Anti-laminin antibodies were able to inhibit the invasion of cultured cells by trypomastigotes (62-75%), 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-binding 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 involved in the reaction which is independent of the carbohydrate moieties from both ligand and receptor. It is also shown that LBG is a member of the Tc-85 family, previously shown to be related to the invasion process of the parasite.
Giordano
R
R
Departamento de Bioquímica, Universidade de São Paulo, Brasil.
Chammas
R
R
Veiga
S S
SS
Colli
W
W
Alves
M J
MJ
D000818:Animals; D001665:Binding Sites; D050260:Carbohydrate Metabolism; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism; D006023:Glycoproteins / Q000302:isolation & purification / Q000378:metabolism; D007797:Laminin / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism*; D010446:Peptide Fragments / Q000302:isolation & purification / Q000378:metabolism; D015800:Protozoan Proteins / Q000302:isolation & purification / Q000378:metabolism*; D014349:Trypanosoma cruzi / Q000378:metabolism* / Q000472:pathogenicity
D002352:Carrier Proteins; D006023:Glycoproteins; D007797:Laminin; D010446:Peptide Fragments; D015800:Protozoan Proteins