The recognition of haemoglobin by antibodies raised for the immunoassay of beta-amyloid.
Canine and porcine cerebrospinal fluid (CSF) were fractionated by size exclusion chromatography and analysed by a luminescence enzyme linked immunosorbent assay (ELISA) configured to detect beta-amyloid. A peak of activity was observed in the CSF consistent with the molecular weight of beta-amyloid. When CSF contaminated with blood was analysed an additional peak of immunoreactivity at a higher molecular weight was observed. The peak of activity was found to be derived from cross-reactivity of the immunoglobulins employed in the ELISA with haemoglobin. These findings are discussed with reference to primary and structural sequence homology between beta-amyloid and haemoglobin from a number of species, the known properties of beta-amyloid and recent clinical reports.
Cutler
P
P
SmithKline Beecham Pharmaceuticals, Harlow, Essex, UK. paul_cutler-1@sbphrd.com
Brown
F
F
Camilleri
P
P
Carpenter
D
D
George
A
A
Gray
C
C
Haran
M
M
Stewart
B
B
D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid* / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004285:Dogs; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006454:Hemoglobins / Q000276:immunology*; D006801:Humans; D017386:Sequence Homology, Amino Acid; D013552:Swine
D016229:Amyloid beta-Peptides; D000911:Antibodies, Monoclonal; D006454:Hemoglobins