Isolation of a 220-Kilodalton Protein With Lectin Properties From a Virulent Strain of Entamoeba histolytica

Abstract

A 220-kilodalton (kDa) protein with lectin properties was isolated from Entamoeba histolytica strain HM1:IMSS and was purified by Sepharose 4B chromatography and electroelution from 5% SDS-polyacrylamide gels. The protein contains 9% carbohydrate by weight; is rich in hydrophobic residues; and is very immunogenic in mice, hamsters, and rabbits. The protein binds to fixed monolayers of MDCK cells and inhibits trophozoite attachment to the cultured cells. The 220-kDa protein agglutinates human erythrocytes, and agglutination is inhibited by micromolar concentrations of hyaluronic acid, chitin, chitin-derived products (chitotriose), and antibodies to the purified protein. The 220-kDa protein is recognized by an antibody to the membrane but not by antibodies to other subcellular fractions. We therefore suggest that this 220-kDa protein with lectin properties is a component of the plasma membrane and could be one of the putative "receptor" molecules involved in cell and/or matrix attachment.

In vitro Entamoeba histolytica adhesion to human endothelium: a comparison using two strains of different virulence

“…However, certain parasite molecules such as a 220-kDa glycoprotein and a sugar-inhibitable lectin of 170 kDa have been proposed as being responsible for the attachment of amebas to other mammalian cells such as Madin and Darby canine kidney (MDCK) cells, leukocytes, rat colonic cells, Chinese hamster ovary cells, and erythrocytes (Ravdin and Guerrant 1981;Ravdin et al 1985;Rosales-Encina et al 1987;Petri et al 1989;Rodríguez et al 1989). Likewise, a comparative analysis using more strains of E. histolytica and other nonpathogenic strains of Entamoeba will be carried out to determine significant differences.…”

Galactose-specific adhesin and cytotoxicity of Entamoeba histolytica

“…In studies using a wide variety of in vitro and in vivo experimental models, at least ®ve dierent types of molecules have been suggested to be responsible for the various types of cell and tissue damage caused by pathogenic amebas, including (1) adhesins (McCoy et al 1994;Petri et al 1987;Rodriguez et al 1989;Rosales-Encina et al 1987), (2) amebapores (Leippe 1997;Leippe et al 1991, (3) phospholipase A Ravdin et al 1985;Vargas-Villarreal et al 1995), (4) collagenase (MunÄ oz et al 1982(MunÄ oz et al , 1984, and (5) cysteine proteinases (Becker et al 1988;Keene et al 1990; Montfort et al 1993;Reed et al 1989). In addition, it has been claimed that in early experimental amebic liver abscesses (Tsutsumi and MartõÂ nez-Palomo 1988;Tsutsumi et al 1984) as well as in early experimental amebic intestinal lesions in hamsters and guinea pigs (MartõÂ nez-Palomo et al 1989), polymorphonuclear leukocytes that come into contact with trophozoites die and disintegrate, releasing lysosomal enzymes that contribute to tissue damage.…”

Proteases fromEntamoebaspp. and Pathogenic Free-Living Amoebae as Virulence Factors

“…The contact between trophozoites and target cells appears to be the first step for cell lysis and phagocytosis. Several molecules are involved in this interaction, including the 260 and 220 kDa lectins and 112 kDa adhesin, which participates in the adherence to epithelial cells and erythrocytes [8, 59–63]. It has been proposed that for the initial amoeba contact or adhesion, surface carbohydrates on the target cell are recognized by specific molecules from the parasite.…”