title: Evidence for the existence of ganglioside molecules in the antigen of Entamoeba histolytica.
abstract: Gangliosides were found to be present in Entamoeba histolytica. They were extracted from lyophilized trophozoites of the pathogenic strain HM-1:IMSS and purified by high performance thin-layer chromatography. Two resorcinol-positive bands, comigrating with GM2 and GD1a were demonstrated, revealing the existence of ganglioside molecules in Entamoeba histolytica. The GM2 content, determined as lipid-bound sialic acid, was 1.5 micrograms/10(8) amoebae, the content of the GD1a comigrating band was 0.32 microgram/10(8) amoebae. The identity of the GM2 comigrating band was confirmed by TLC immunostaining, using the monoclonal anti-GM2 antibody GMB28. Furthermore, six out of ten anti-amoeba positive sera selectively reacted with the GM2 comigrating band, as revealed by immunostaining on TLC plates. Absorption tests revealed that preincubation of anti-amoeba positive sera with standard GM2 was followed by a significant decrease in the reaction with amoeba trophozoites by indirect immunofluorescence. These results demonstrate that a GM2 comigrating component of Entamoeba histolytica may be one of the antigens responsible for the appearance of circulating antibodies in patients with amoebiasis.
authors.affiliation: Dipartimento di Medicina Sperimentale, Universitä La Sapienza, Roma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Sorice
authors.forename: T
authors.initials: T
authors.lastname: Griggi
authors.forename: G
authors.initials: G
authors.lastname: Nicodemo
authors.forename: T
authors.initials: T
authors.lastname: Garofalo
authors.forename: M
authors.initials: M
authors.lastname: Marangi
authors.forename: S
authors.initials: S
authors.lastname: Sanguigni
authors.forename: S I
authors.initials: SI
authors.lastname: Becker
authors.forename: D
authors.initials: D
authors.lastname: Mirelman
mesh_terms: D000042:Absorption; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000737:chemistry*; D004748:Entamoeba histolytica / Q000737:chemistry* / Q000276:immunology; D005677:G(M1) Ganglioside / Q000032:analysis / Q000276:immunology; D005679:G(M3) Ganglioside / Q000032:analysis / Q000276:immunology; D005732:Gangliosides / Q000032:analysis* / Q000276:immunology; D006801:Humans
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D005679:G(M3) Ganglioside; D005732:Gangliosides; C021298:ganglioside, GD1a; D005677:G(M1) Ganglioside