A highly sensitive immunoenzymometric assay for the determination of angiogenin.

A polyclonal antibody to human recombinant angiogenin was prepared in rabbits using a Pam3CysSerGly conjugate. The antibody was then used to develop the first highly sensitive enzyme-labelled immunometric assay for this vascularisation inducing and tumour associated protein. The assay was suitable for quantification of angiogenin in body fluids between 2.5 and 0.05 micrograms/l. The mean intra-assay imprecision was 6.0% and the inter-assay imprecision 7.9%. Angiogenin in human plasma was found to lie in the range of 0.38 to 0.11 mg/l with a mean of 0.25 +/- 0.07 mg/l.