Evidence for the existence of ganglioside molecules in the antigen of Entamoeba histolytica.
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.
Sorice
M
M
Dipartimento di Medicina Sperimentale, Universitä La Sapienza, Roma, Italy.
Griggi
T
T
Nicodemo
G
G
Garofalo
T
T
Marangi
M
M
Sanguigni
S
S
Becker
S I
SI
Mirelman
D
D
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
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D005679:G(M3) Ganglioside; D005732:Gangliosides; C021298:ganglioside, GD1a; D005677:G(M1) Ganglioside