A recombinant cysteine-rich section of the Entamoeba histolytica galactose-inhibitable lectin is efficacious as a subunit vaccine in the gerbil model of amebic liver abscess.
The 170-kDa subunit of the galactose-inhibitable adherence lectin of Entamoeba histolytica mediates attachment to colonic mucins and host cells. The DNA fragment encoding the 170-kDa subunit was produced by polymerase chain reaction (PCR) and divided into four sections by restriction endonucleases. The third section (designated LC3, base pairs 2273-3397) encodes a cysteine-rich fusion protein that was recognized by adherence-inhibitory anti-lectin monoclonal antibodies and serum antibodies from 95% of subjects with amebic liver abscess. Immunization of gerbils with purified recombinant LC3-encoded protein (10 micrograms) with Titermax adjuvant elicited a high-titer serum anti-LC3 IgG antibody response and protective immunity against intrahepatic challenge with 0.5 x 10(6) virulent axenic trophozoites (strain HM1:IMSS; 71% vaccine efficacy, P < .01). In summary, a recombinant cysteine-rich portion of the 170-kDa lectin subunit was highly antigenic, immunogenic, and effective as a subunit vaccine in an experimental animal model of amebic liver abscess.
Soong
C J
CJ
Department of Medicine, Case Western Reserve University, Cleveland, Ohio.
Kain
K C
KC
Abd-Alla
M
M
Jackson
T F
TF
Ravdin
J I
JI
D000818:Animals; D001483:Base Sequence; D003545:Cysteine / Q000032:analysis; D004195:Disease Models, Animal; D004748:Entamoeba histolytica / Q000276:immunology*; D005690:Galactose / Q000037:antagonists & inhibitors*; D005849:Gerbillinae; D007114:Immunization; D037102:Lectins / Q000235:genetics / Q000276:immunology*; D008101:Liver Abscess, Amebic / Q000517:prevention & control*; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016052:Protozoan Vaccines / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology*
D037102:Lectins; D016052:Protozoan Vaccines; D014614:Vaccines, Synthetic; D003545:Cysteine; D005690:Galactose