Production and specificity of antibodies directed toward 3,4,5-trimethoxyphenylethylamine, 3,4-dimethoxyphenylethylamine and 2,5-dimethoxy-4-methylamphetamine

Adjuvants for vaccines to drugs of abuse and addiction

Immunotherapeutic vaccines to drugs of abuse, including nicotine, cocaine, heroin, oxycodone, methamphetamine, and others are being developed. The theoretical basis of such vaccines is to induce antibodies that sequester the drug in the blood in the form of antibody-bound drug that cannot cross the blood brain barrier, thereby preventing psychoactive effects. Because the drugs are haptens a successful vaccine relies on development of appropriate hapten-protein carrier conjugates. However, because induction of high and prolonged levels of antibodies is required for an effective vaccine, and because injection of T-independent haptenic drugs of abuse does not induce memory recall responses, the role of adjuvants during immunization plays a critical role. As reviewed herein, preclinical studies often use strong adjuvants such as complete and incomplete Freund's adjuvant and others that cannot be, or in the case of many newer adjuvants, have never been, employed in humans. Balanced against this, the only adjuvant that has been included in candidate vaccines in human clinical trials to nicotine and cocaine has been aluminum hydroxide gel. While aluminum salts have been widely utilized worldwide in numerous licensed vaccines, the experience with human responses to aluminum salt-adjuvanted vaccines to haptenic drugs of abuse has suggested that the immune responses are too weak to allow development of a successful vaccine. What is needed is an adjuvant or combination of adjuvants that are safe, potent, widely available, easily manufactured, and cost-effective. Based on our review of the field we recommend the following adjuvant combinations either for research or for product development for human use: aluminum salt with adsorbed monophosphoryl lipid A (MPLA); liposomes containing MPLA [L(MPLA)]; L(MPLA) adsorbed to aluminum salt; oil-in-water emulsion; or oil-in-water emulsion containing MPLA.

The development of enzyme-linked immunosorbent assays (ELISA) for the catecholamines adrenalin and noradrenalin

Monoclonal antibodies have been raised against adrenalin and noradrenalin and used as the basis of enzyme-linked immunosorbent assays (ELISA) to detect and estimate the concentrations of these catecholamines. Inhibition assays are described, with sensitive quantification in the range from 1 mg/ml to 100 pg/ml. Cross-reactivity assays reveal that neither assay is subject to interference by catecholamine metabolites at concentrations less than 100 ng/ml and 1 micrograms/ml respectively. Isolation and quantification of both catecholamines from clinical samples is discussed and the potential application of these ELISAs in a clinical setting is proposed.

Preparation of antibodies to catecholamines and metabolites--syntheses of various immunogens and characterization of the resulting antibodies

The synthesis of antigens of the haptens p-tyramine, octopamine, synephrine, dopamine, normetanephrine, beta-(3,4-dichlorophenyl)-ethylamine and 3-fluoro-tyramine is described. The coupling of the haptens to the carrier protein was performed either via the side chain by means of succinic anhydride, or through the phenolic ring via an aminomethyl group which was introduced by a Mannich reaction. Antisera to these haptens were produced in rabbits by immunization with these antigens. The antisera were characterized by determination of titer and specificity (p-tyramine, synephrine, normetanephrine). The possibility is discussed of using antisera to p-hydroxyphenylethylamine for a radioimmunological determination of catecholamines.

Methodical investigation of the production of antibodies towards 3,4-dimethoxyphenylethylamine

In this study the synthesis of various antigens from 3,4-dimethoxyphenylethylamine (3,4-DMPEA) is described. Antigen A was formed by coupling the acylated side chain of 3,4-DMPEA to the protein, while antigen B was synthesized by introducing an acylated amino group to the benzene ring and linking this reactive group to the protein. With antigen A an antiserum with a titer of 1 : 16000 could be raised, while with antigen B coupled to human albumin and bovine gamma-globulin the antiserum had a titer of 1 :1000 and 1 : 4000. Antibodies formed by immunization with antigen A exhibited a high specificity for substituents of the benzene ring, but were less specific for substituents of the side chain. Antibodies formed by treatment with the antigen B were specific for both kinds of substituents. So far, it has not been possible to harvest any specific antibodies towards the corresponding antigens of dopamine.

Immunologic studies on drug addiction: III. Antibodies reactive with cocaine metabolites and their use for drug detection

Antisera which react with the major metabolites of cocaine have been prepared in rabbits and a hemagglutination-inhibition (HI) test which detects these metabolites in urine or serum in concentrations of 1 ng/ml is described. A comparison of this test with alternate detection procedures shows excellent agreement at comparable sensitivity levels. HI tests on simian and human biological specimens suggest that the use of cocaine remains detectable for at least 3 days after administration of a minimal pharmacologically active dose. Combination of physical separation of drug metabolites with immunoassay procedures indicates that benzoylecgonine and ecgonine are the immunoreactive cocaine metabolites found in human urine. While it was possible to apply the HI test at maximal sensitivity to human sera and to murine or simian urine specimens, interference was encountered with some human urine specimens. Preliminary data suggest that by reducing the sensitivity of the test to a threshold of 200 ng/ml this interference can be overcome.

Specificity of the antibody receptor site to D-lysergamide: model of a physiological receptor for lysergic acid diethylamide

Antibodies to D-lysergic acid have been produced in rabbits and guinea pigs and a radioimmunoassay for the hapten was developed. The specificity of this lysergamide-antilysergamide reaction was determined by competitive binding with unlabeled lysergic acid diethylamide (LSD), psychotomimetic drugs, neurotransmitters, and other compounds with diverse structures. LSD and several related ergot alkaloids were potent competitors, three to seven times more potent than lysergic acid itself. The N,N-dimethyl derivatives of several compounds, including tryptamine, 5-hydroxytryptamine, 4-hydroxytryptamine, 5-methoxytryptamine, tyramine, and mescaline, were only about ten times less effective than lysergic acid, even though these compounds lack some of the ring systems of lysergic acid. The pattern of inhibition by related compounds with various substituents suggests that the antibody receptor site recognizes structural features resembling the LSD molecule. In particular, the aromatic nucleus and the dimethylated ethylamine side chain in phenylethylamine and tryptamine derivatives may assume in solution a conformation resembling ring A and the methylated nitrogen in ring C of LSD. Among the tryptamine derivatives, a large percentage of the most potent competitors are also psychotomimetic compounds.