Trypanosoma cruzi: identification of a galactose-binding protein that binds to cell surface of human erythrocytes and is involved in cell invasion by the parasite.
Trypanosoma cruzi must invade mammalian host cells to replicate and complete its life cycle. Almost all nucleated mammalian cells can be invaded by the parasite following a receptor-ligand recognition as an early prerequisite. In this work, we describe a 67-kDa lectin-like glycoprotein that binds to desialylated human erythrocyte membranes in a galactose-dependent way. This protein is present on the parasite surface in both infective and non-infective stages of T. cruzi. More interestingly, we demonstrate by lectin-immuno-histochemistry assays that the 67kDa protein is involved in the recognition of host-cell receptors in mouse cardiac tissue and human cardiac aortic endothelium and mammary artery tissue. Moreover, antibodies against the 67kDa glycoprotein inhibit in vitro host-cell invasion by 63%. These data suggest that the 67kDa glycoprotein in vivo is needed for host-cell invasion by T. cruzi.
INTEBIO, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, (3000) Santa Fe, Argentina. asilber@iq.usp.br
A M
AM
Silber
I S
IS
Marcipar
C
C
Roodveldt
P
P
Cabeza Meckert
R
R
Laguens
A J
AJ
Marcipar
D000818:Animals; D015153:Blotting, Western; D002135:Calcium-Binding Proteins; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D004730:Endothelium, Vascular / Q000378:metabolism / Q000469:parasitology; D004910:Erythrocyte Membrane / Q000378:metabolism* / Q000469:parasitology; D005455:Fluorescent Antibody Technique; D005690:Galactose / Q000378:metabolism; D006321:Heart / Q000469:parasitology; D015801:Helminth Proteins / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007150:Immunohistochemistry; D037102:Lectins; D051379:Mice; D008807:Mice, Inbred BALB C; D009004:Monosaccharide Transport Proteins / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D033902:Periplasmic Binding Proteins; D011817:Rabbits; D014349:Trypanosoma cruzi / Q000737:chemistry / Q000502:physiology*
D002135:Calcium-Binding Proteins; D015801:Helminth Proteins; D007106:Immune Sera; D037102:Lectins; D009004:Monosaccharide Transport Proteins; D033902:Periplasmic Binding Proteins; C023550:galactose-binding protein; D005690:Galactose