John J. Madden

Binding of naloxone to human T lymphocytes

Purified T lymphocytes have a specific binding site for naloxone, the opiate antagonist. The KD for the site was 50.6 +/- 2.4 nM, while the Hill coefficient (n) was 1.67 +/- 0.16, indicating a degree of positive cooperativity of ligand binding. The bound naloxone was partially displaceable by various opiate agonists including morphine (56%), beta-endorphin (61%), met5- and leu5-enkephalin (40% each), [D-ala2, D-leu5]-enkephalin (78%) and [D-ala2, D-leu5]-enkephalinamide (66%). Virtually all of the binding capacity was recovered in the particulate membrane fraction after sonic lysis of the cells. There was great interindividual variability in Bmax between samples, suggesting a possible mechanistic basis for the variability in drug action seen between different individuals.

Coordinate and independent effects of heroin, cocaine, and alcohol abuse on T-cell E-rosette formation and antigenic marker expression

Simultaneous and independent use of cocaine and alcohol by heroin addicts was shown to variably modulate the ability of their T cells to form E-rosettes with sheep erythrocytes (E). As reported previously, the percentages of E-rosette-forming T cells of both active and total types were depressed in association with heroin addiction. We show here that the kinetic curve of the rate of E-rosette formation is also depressed by heroin use and that the use of cocaine but not alcohol by heroin addicts reverses depression of E-rosette formation by heroin. The percentages of E-rosette-forming T cells from the bloods of heroin addicts who used both alcohol and cocaine, as well as the kinetic rate curves of E-rosette formation, were intermediate between the essentially normal levels found for heroin addicts who used cocaine and the severely depressed levels evident for users of heroin alone or heroin plus alcohol. Modulation of the levels of E-rosette formation by alcohol used in conjunction with cocaine and/or heroin was variably dose dependent. Polydrug effects evident by analyses of E-rosette formation were not seen when the percentages of lymphocytes reactive with LYT-3 (anti-E-receptor, 9.6 epitope) and OKT-3 (anti-total T cell) monoclonal antibodies were assessed cytofluorometrically, although the data suggested that subnormal percentages of LYT-3+ T cells were present when heroin addicts also used cocaine. These findings are relevant to basic understanding of T-cell physiology from a neuroimmunological perspective and also suggest ways that addictive drugs may modulate the immunocompetence of drug addicts.

Opiate binding sites in the cellular immune system: expression and regulation

The direct actions of opiates on the mammalian immune system depend on the existence of ligand binding sites either on the surface of the affected cell or in the interior of the cell. With the cloning of various opiate receptors from neuronal tissue, numerous researchers have screened leukocyte cDNA libraries for the expression of these receptors with some positive results. However, the pattern of expression of neuronal opiate receptors in the cellular immune system does not completely explain the biological action of opiates there. Several possibilities could account for this non-congruence including differential expression of the receptors as determined by such factors as cell population or prior history of the cells; the existence of sequence modified versions of the neuronal receptors such that the amplification methods miss their presence; or the opiates act by a different, non-receptor mechanism in the cellular immune system.

The Brain Immune Axis and Substance Abuse

Proceedings from the second annual symposium on the above-titled topic held in June 1994 in Palm Beach, Florida Papers address the direct effects of drugs of abuse on various components of the immune system, as well as those mediated indirectly by the central nervous system and the neuroendocrine sy

The morphine-binding site on human activated T-cells is not related to the mu opioid receptor

Mitogen activation of human T-lymphocytes induces a morphine-binding site. Morphine binding is displaceable by beta-endorphin (1--31) and (--)-naloxone but not DAMGO. This site is not stereoselective for (--)-morphine. T-lymphocytes, expressing this binding site, were assayed by reverse-transcription polymerase chain reaction (RT-PCR) for expression of hMOR-1 mRNA. Several primer sets were used and each assay compared with cells known to express human or mouse MOR-1 mRNA. Neither hMOR-1 nor any homologous receptor was detected in human T-lymphocytes. Therefore, the morphine-binding site on mitogen-activated T-lymphocytes is unlikely to be closely related to hMOR-1.

Drugs of abuse, immunomodulation, and AIDS

Cellular Mechanisms Involved in the Modulation of the Immune System by Drugs of Abuse S.L. Chang, et al. Immunomodulation of Macrophage Functions by Opioids R. Gomez-Flores, R.J. Weber. Morphine Accelerates the Progression of Sepsis in an Experimental Sepsis Model S. Roy, et al. Morphine Depresses Macrophage Numbers and Function in Mouse Spleens T.K. Eisenstein, et al. Morphine Depresses Macrophage Numbers and Function in Mouse Spleens T.K. Eisenstein, et al. Centrally-Mediated Opioid-Induced Immunosupression: Elucidation of Sympathetic Nervous System Involvement W.J. Brinkman, et al. The Expression of Interleukin-1b Converting Enzyme (ICE) in Rat is Decreased Following Chronic Exposure to Morphine Gao-de Wu, et al. Opioid Receptor Gene Expression in the Porcine Immune System M.S. Pampusch, et al. The Effects of Interaction Between Morphine and Interleukin-1 on the Immune Response S.L. Chang, et al. Morphine Alters the Immune Response to Influenza Virus Infection in Lewis Rats M.E. Coussons-Read, et al. Orphan Opioid Receptor Oligonucleotide Inhibit HIV-1 Expression in Human Brain Cells C.C. Chao, et al. Opiate Effects on in Vitro Human Retroviral Infection S.B.Nyland, et al. FIV: A Lentivirus Model for Opiate Effects on Disease J.-N. Billaud, T.R. Phillips. 21 Additional Articles. Index.

Effects of Cocaine and Other Drugs of Abuse on Immune Function

Approximately 19 years ago, Falek et al. (1) reported that heroin addicts frequently exhibit abnormally high levels of cytogenetic damage in their T-lymphocytes after mitogenic stimulation in vitro with the plant lectin, phytohemag-glutinin. Later, Madden et al. (2) showed that this damage was probably due to altered DNA-repair capacity of lymphocytes. Less obvious, perhaps, than the genetic implications of these findings were their immunological implications, which, in fact, were significant.

Parallel increases in sister-chromatid exchanges at base level and with UV treatment in human opiate users.

The SCE base level frequency and SCE levels induced by far-UV (254 nm) treatment of cells in early G1 and early S phases of the cell cycle were significantly higher in leukocytes from heroin addicts as compared to controls. The increased SCE levels in addicts was greatest at base level and smallest after UV irradiation of cells in S phase. These results corroborate and extend our previous findings of increased chromosome damage and reduced DNA-repair synthesis in heroin users. Since opiates do not directly damage DNA, the elevated cytogenetic effects associated with opiate use probably arise from secondary promotional effects related to opiate-mediated alterations in leukocyte metabolism.

Biogenetic effects of opiates

Our laboratories have shown that opiate addicts have higher chromosome damage and sister chromatid exchange frequencies, and that these effects are more pronounced in the addicts when we employ enhanced culturing assays developed in our laboratory. We have also demonstrated that opiates diminish DNA repair capacity and reduce immunoresponsiveness as measured by T-cell E-rosetting and other assays. These interactions of opiates with T-lymphocytes may regulate cell metabolism and could thereby be responsible for the sensitivity of cells from opiate addicts to both genotoxic damage and immunological effects.

Increased rate of E-rosette formation by T lymphocytes of pregnant women who drink ethanol

Ethanol use by pregnant women increased, in a dose-dependent manner, the rate of sheep erythrocyte rosette (E-rosette) formation with T lymphocytes. The time curve for E-rosette formation by T cells from nondrinking subjects was biphasic, with a rapid formation of half the E-rosettes within the first 16 min, followed by a much slower rate for E-rosette formation until the maximal T-cell percentage was reached overnight. For pregnant drinkers, greater than 85% of the E-rosettes formed during the initial rate period, with a concomitant smaller number forming during the overnight incubation. Despite the faster initial rate of E-rosette formation in the drinking subjects, the total percentage T cells was the same for both groups. Other demographic factors, like tobacco or marijuana use, or trimester, did not significantly contribute to the observed differences. An increase in the rate of E rosetting was also obtained by incubating lymphocytes from nondrinkers overnight in physiologically attainable concentrations of ethanol (less than or equal to 0.1%). These results demonstrate that drinking by pregnant women, even at relatively moderate levels (2 oz/week absolute ethanol), causes alterations in their cellular immune systems. With the ability of ethanol to cross the placental barrier and persist in utero, it is apparent that these levels of ethanol have the potential to affect the developing fetal immune system.