Development of immunoassays of catecholamines and their metabolites

Abstract EN

Catecholamines take the role of neurotransmitters and hormones and are involved in many diseases.

Sensitive immunoassays for catecholamines and their metabolites were required to study the diagnoses of diseases.

First, we achieved success in producing specific antibodies for catecholamines and basic metabolites using each antigen.

We applied a monoclonal antibody to 3-methoxy-4- hydroxyphenylglycol to measure the concentrations to diagnose depression.

The acidic homovanillic acid (HVA) and d-3-methoxy-4-hydroxymandelic acid (VMA) were useful in mass screening of neuroblastoma using monoclonal antibodies.

The paper reviews these developments for future use.An antigen is important to produce the specific antibody.

The amino acid residue of each catecholamine and l-3,4- dihydroxyphenylalanine protected with N-maleyl group as well as basic metabolites was reacted with bovine serum albumin using Mannich reaction in the presence of formaldehyde.

The N-maleyl group of the conjugate was moderately liberated to give rise to the antigen.

The antigen was injected with Freund’s Complete Adjuvant to the rabbit or mouse.

The conventional or monoclonal antibody was used for radioimmunoassay or enzyme immunoassay.Each immunoassay showed high specificity in discriminating not only the fine structure of the hapten but also body ingredients.Thekits ofHVAandVMAwereuseful inscreeningtheurinefromtheinfant with neuroblastoma.

The secret of specific antibody preparation is dependent on the syntheticmethodof theconjugation,whichischemicallymoderate.Thepreparationof antibody requires long time to increase the affinity.

Thus, the methods of antibody preparation are established and repeatable for anyone.The mass screening of neuroblastoma with HVA and VMA was easily applied to infants.

Our previous results had established immunoassays for all members of catecholamines and their metabolites for diagnosis and research