title: Humoral and mucosal IgA antibody response to a recombinant 52-kDa cysteine-rich portion of the Entamoeba histolytica galactose-inhibitable lectin correlates with detection of native 170-kDa lectin antigen in serum of patients with amebic colitis.
abstract: Humoral and mucosal IgA responses to a recombinant cysteine-rich portion (designated LC3) of the Entamoeba histolytica galactose-inhibitable lectin's 170-kDa subunit were determined in patients with amebic colitis. All patients had 170-kDa amebic antigen in serum, compared with 1 of 50 cyst passers and 1 of 31 controls (P < .01). Seven days after treatment, serum and fecal 170-kDa antigen became undetectable in 12 of the 13 patients (P < .001). Serum anti-LC3 IgA was found in 83.8% of colitis patients, compared with 2% of controls and 12% of asymptomatic cyst passers (P < .001). Salivary and fecal anti-LC3 IgA levels were higher in patients than in cyst passers (P < .001). In conclusion, in amebic colitis, development of humoral and mucosal IgA responses to the recombinant LC3-encoded protein correlates with detection of amebic 170-kDa antigen in serum and feces.
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
authors.forename: I
authors.initials: I
authors.lastname: Abou-el-Magd
authors.forename: C J
authors.initials: CJ
authors.lastname: Soong
authors.forename: A M
authors.initials: AM
authors.lastname: el-Hawey
authors.forename: J I
authors.initials: JI
authors.lastname: Ravdin
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood / Q000302:isolation & purification*; D000953:Antigens, Protozoan / Q000097:blood / Q000302:isolation & purification*; D016022:Case-Control Studies; D003092:Colitis / Q000276:immunology* / Q000469:parasitology*; D004748:Entamoeba histolytica / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces; D005690:Galactose / Q000494:pharmacology*; D006801:Humans; D007070:Immunoglobulin A / Q000302:isolation & purification; D007074:Immunoglobulin G / Q000302:isolation & purification; D007413:Intestinal Mucosa / Q000276:immunology* / Q000469:parasitology; D037102:Lectins / Q000037:antagonists & inhibitors / Q000276:immunology*; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000276:immunology; D012463:Saliva
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D037102:Lectins; D011994:Recombinant Proteins; D005690:Galactose