Investigation of the assay of AFB1-albumin adducts using proteolysis products in ELISA.
Epidemiological evidence of the involvement of aflatoxins in the aetiology of human liver cancer has led to an increasing interest in the development of appropriate techniques for monitoring human exposure. The assay for aflatoxin adducts in albumin has a better potential for assessing long-term exposure than analyses of urine samples, and several protocols for ELISA of these adducts, following proteolysis of albumin, have been examined. However, there is usually an incomplete release of a major adduct, aflatoxin-lysine, even after prolonged hydrolysis, and the adduct is very unstable under some conditions of proteolysis for unknown reasons. Therefore, before such techniques can be recommended for general application, the significance of such factors in the quantitive estimation of aflatoxin adducts needs to be evaluated. This study has detected the presence of a considerable fraction of aflatoxin-modified material, produced by proteolysis of in vivo aflatoxin-modified rat albumin or in vitro modified bovine albumin, and which is not recognized in ELISA by an anti-aflatoxin polyclonal antibody having a wide spectrum of aflatoxin metabolite detection. This fraction increases in parallel with the proteolysis protocols.
Olubuyide
I O
IO
Medical Research Council, Toxicology Unit, Carshalton, Surrey, UK.
Makarananda
K
K
Judah
D J
DJ
Neal
G E
GE
D016604:Aflatoxin B1; D000348:Aflatoxins / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood* / Q000494:pharmacology; D000818:Animals; D001667:Binding, Competitive; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D019286:Endopeptidase K; D004797:Enzyme-Linked Immunosorbent Assay; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D012697:Serine Endopeptidases; D012709:Serum Albumin / Q000032:analysis*; D012710:Serum Albumin, Bovine / Q000032:analysis*
D000348:Aflatoxins; D012709:Serum Albumin; C052669:aflatoxin B1-bovine serum albumin; D012710:Serum Albumin, Bovine; D016604:Aflatoxin B1; D012697:Serine Endopeptidases; D019286:Endopeptidase K