Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The interference of immunoglobulins in the radioimmunoassay (RIA) of human beta-endorphin was investigated. Human IgM showed no cross-reactivity. Human IgA showed a weak cross-reaction, but the dilution curve of IgA did not show parallelism with the standard curve of beta-endorphin, thus indicating its antigenic difference. The dilution curves of human IgG showed 0.18% displacement with respect to the human beta-endorphin standard curve, with good parallelism. Moreover, five patients with multiple myeloma of the IgG type showed falsely elevated beta-endorphin levels. We investigated the possibility that certain IgGs may be responsible for the displacement of [125I]beta-endorphin in the beta-endorphin kit. The apparent beta-endorphin level of plasma from multiple myeloma patients was markedly decreased after affinity chromatography of the serum on protein A-Sepharose. In another 3 patients with multiple myeloma, we examined IgG interference by measuring the beta-endorphin levels in their lyophilized IgG diluted with saline. The results demonstrated high values of 20.2, 25.5 and 21.2 pmol/l respectively, also showing good parallelism. These immunological parallels to human beta-endorphin verify that a part of the amino acid sequence of human IgG is similar to that of human beta-endorphin. Consequently, in the measurement of beta-endorphin with polyclonal antibody, the results may sometimes be spuriously high due to cross-reaction with IgG, e.g., in patients with IgG myeloma. To avoid IgG interference, a specific monoclonal antibody to synthetic beta-endorphin should be used rather than polyclonal antibodies.
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PMID:Interference of immunoglobulins in the radioimmunoassay of human beta-endorphin. 208 65

After the recent demonstration of the facilitatory effect exerted by corticotropin-like intermediate lobe peptide (CLIP or adrenocorticotropic hormone (ACTH) 18-39) on paradoxical sleep in the rat (Chastrette and Cespuglio, 1985), we undertook the production of monoclonal antibodies against this peptide. Wistar rats were immunized against CLIP and their spleen cells fused with mouse myeloma cells. After recloning, 25 supernatants were found to give positive immunohistochemical reactions in the rat brain. In immunohistochemical tests performed by preabsorption, the 25 supernatants presented similar properties, i.e. recognized CLIP, ACTH (1-39) and ACTH (25-39), but not ACTH (1-24) and the C-terminal fragment (34-39). We assume that the epitope(s) recognized by the 25 supernatants is (are) located between the amino-acids Asn25 and Ala34 of the CLIP molecule. The immunoreactivity observed in the rat brain and hypophysis with this antibody was distributed with a pattern quite similar to that described for anti-ACTH antibodies. A main group of immunoreactive cell bodies was located in the mediobasal hypothalamus and a small group in the nucleus of the solitary tract. Immunoreactive fibres were distributed from the olfactory nucleus to the spinal cord and formed particularly rich networks in the hypothalamus and preoptic area. Among other locations, immunoreactive axons were also present in the brainstem centres involved in the control of the sleep-waking cycle, which is in accordance with the influence of CLIP on paradoxical sleep. Using Abercrombie's formula, the number of immunoreactive cells in the mediobasal hypothalamus was estimated at about 3000 neurons. We conclude that our monoclonal anti-CLIP antibody can be considered as a good marker of proopiomelanocortin neurons.
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PMID:A monoclonal antibody directed against CLIP (ACTH 18-39). Anatomical distribution of immunoreactivity in the rat brain and hypophysis with quantification of the hypothalamic cell group. 216 15

Six myeloma cell hybrids producing antibodies to human beta-endorphin were isolated from a single mouse spleen. The monoclonal antibodies displayed different binding patterns with the antigen. We report the characterization of one antibody which recognizes the tetrapeptide Tyr-Gly-Gly-Phe representing the message sequence found at the NH2 terminus of all naturally occurring mammalian opioid peptides. Competition experiments in radioimmunoassay and immunohistochemistry show that the antibody fails to bind the beta-endorphin precursor beta-lipotrophin, does not discriminate among opioid peptides that share the same message sequence but have different COOH-terminal extensions, and does not react with pharmacologically inactive derivatives of beta-endorphin. The antibody recognition of the message sequence of natural opioid peptides is sensitive to those molecular changes that affect their receptor binding competence.
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PMID:Monoclonal antibody to the message sequence Tyr-Gly-Gly-Phe of opioid peptides exhibits the specificity requirements of mammalian opioid receptors. 619 29