Premium
Binding Characteristics of a Monoclonal β‐Endorphin Antibody Recognizing the N‐Terminus of Opioid Peptides
Author(s) -
Gramsch Christian,
Meo Tommaso,
Riethmüller Gert,
Herz Albert
Publication year - 1983
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1983.tb13560.x
Subject(s) - monoclonal antibody , chemistry , polyclonal antibodies , radioimmunoassay , opioid peptide , antibody , endorphins , tyrosine , enkephalin , microbiology and biotechnology , biochemistry , opioid , receptor , biology , endocrinology , immunology
The present paper describes the isolation and characterization of a clone of hybrid myelomas (3‐E7) secreting a mouse monoclonal antibody to β ‐endorphin. An examination of its specificity against a series of human β ‐lipotropin fragments and other opioid peptides revealed that the N‐terminus portion of β ‐endorphin is the determinant. Complete or almost complete cross‐reactivity was obtained to methionine‐ and leucine‐enkephalin, β ‐lipotropin 60–65, and BAM 22; partial cross‐reactivity was seen to dynorphin 1–13 and α ‐neo‐endorphin, whereas β ‐lipotropin, α‐N ‐acetyl‐ β ‐endorphin, Des‐Tyr 1 ‐ β ‐endorphin, in addition to a series of synthetic enkephalin derivatives, completely lacked cross‐reactivity. The use of the monoclonal antibody in radioimmunoassay (RIA) for β ‐endorphin resulted in a lower sensitivity related to respective polyclonal antibodies. An increase of 100% in tracer binding could, however, be obtained by use of β ‐endorphin iodinated with its N‐terminal tyrosine protected by coupling to an antibody. A solid‐phase RIA was developed involving the internally 3 H‐labeled monoclonal antibody, which resulted in a 10‐fold increase in sensitivity as compared with the homogenous RIA. These data indicate that for the binding to this antibody a tyrosine residue in position 61 is essential, and it thus recognizes a site that is of functional significance for many naturally occurring opioid peptides.