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Hu Y, Zhao Z, Ehrich M, Zhang C. Formulation of Nanovaccines toward an Extended Immunity against Nicotine. ACS APPLIED MATERIALS & INTERFACES 2021; 13:27972-27982. [PMID: 34105952 PMCID: PMC9201939 DOI: 10.1021/acsami.1c07049] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nicotine vaccines have been investigated to assist with smoking cessation. Because smoking cessation is a long process, past nicotine vaccines required multiple injections to achieve long-term efficacy. It would be of great significance if extended efficacy can be achieved with fewer injections. Here, we report the assembly of lipid-polylactic acid (PLA) and lipid-poly(lactic-co-glycolic acid) (PLGA) hybrid nanoparticle (NP) based nicotine vaccines. Mice immunized with the lipid-PLGA vaccine produced higher titers of nicotine-specific antibodies than the lipid-PLA vaccine in short-term. However, the lipid-PLA vaccine was found to induce long-lasting antibodies. Three months after the immunization, only mice that received first two injections of the lipid-PLGA vaccine and a third injection of the lipid-PLA vaccine achieved a significantly lower brain nicotine concentration of 65.13 ± 20.59 ng/mg than 115.88 ± 37.62 ng/mg from the negative controls. The results indicate that not only the stability of the vaccines but also the combination of the vaccines impacted the long-term efficacy of the immunization. Lastly, both the body weight and the histopathology study suggest that the vaccines were safe to mice. These findings suggest that long-term immunity against nicotine can be realized by a rational administration of nanovaccines of different levels of stability.
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Affiliation(s)
- Yun Hu
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Zongmin Zhao
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Marion Ehrich
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Chenming Zhang
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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Abstract
Immunotherapies are under development as a new approach to the treatment of substance dependence. The drugs of abuse currently being tested using this new approach are nicotine, cocaine, phencyclidine and methamphetamine. In laboratory animal models, a range of immunotherapies, including vaccines, monoclonal antibodies and catalytic antibodies, have been shown to reduce drug seeking. In human clinical trials, cocaine and nicotine vaccines have been shown to induce antibody titers while producing few side effects. Studies in humans determining how these vaccines interact in combination with their target drug are underway. Overall, immunotherapy offers a range of potential treatment options: drug treatment, as well as the treatment of overdose, prevention of brain or cardiac toxicity and fetal protection in pregnant drug abusers.
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Affiliation(s)
- Margaret Haney
- College of Physicians and Surgeons of Columbia University and the New York State Psychiatric Institute, Department of Psychiatry, New York, NY 10032, USA.
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Esterlis I, Hannestad JO, Perkins E, Bois F, D’Souza DC, Tyndale RF, Seibyl JP, Hatsukami DM, Cosgrove KP, O’Malley SS. Effect of a nicotine vaccine on nicotine binding to β2*-nicotinic acetylcholine receptors in vivo in human tobacco smokers. Am J Psychiatry 2013; 170:399-407. [PMID: 23429725 PMCID: PMC3738000 DOI: 10.1176/appi.ajp.2012.12060793] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Nicotine promotes smoking partly by binding to β2-containing nicotinic acetylcholine receptors (β2*-nAChRs) in the brain. Smoking one tobacco cigarette results in occupation of 80% of β2*-nAChRs for more than 6 hours. This likely contributes to maintenance of smoking dependence and cessation difficulty. Developing nicotine vaccines could improve treatments. The authors used [123I]5-I-A-85380 single photon emission computed tomography (SPECT) to evaluate the effect of 3'-AmNic-rEPA on the amount of nicotine that binds to β2*-nAChRs in smokers' brain cortical and subcortical regions. METHOD Eleven smokers who smoked an average of 19 cigarettes per day, had smoked for 10 years on average, and met criteria for nicotine dependence were given SPECT scans on two days: before and after immunization with 4-400 μg of 3'-AmNic-rEPA. On scan days, three 30-minute baseline emission scans were followed by intravenous administration of nicotine (1.5 mg/70 kg body weight) and up to nine 30-minute emission scans. RESULTS β2*-nAChR availability was quantified as VT/fP (total distribution volume divided by free plasma concentration), and nicotine binding was derived by the Lassen plot approach. Immunization led to a 12.5% reduction in nicotine binding. Nicotine bound to β2*-nAChRs correlated positively with nicotine injected before but not after vaccination. The daily number of cigarettes and desire for a cigarette decreased after vaccination. CONCLUSIONS This proof-of-concept study demonstrates that immunization with nicotine vaccine can reduce the amount of nicotine binding to β2*-nAChRs and disrupt the relationship between administered nicotine and nicotine available to occupy β2*-nAChRs.
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Affiliation(s)
- Irina Esterlis
- Department of Psychiatry, Yale University, New Haven, Conneticut, USA.
| | - Jonas O. Hannestad
- Yale University, Department of Psychiatry, CAMH and University of Toronto
| | - Evgenia Perkins
- Yale University, Department of Psychiatry, CAMH and University of Toronto,VACHS, Department of Psychiatry, CAMH and University of Toronto
| | - Frederic Bois
- Yale University, Department of Psychiatry, CAMH and University of Toronto,VACHS, Department of Psychiatry, CAMH and University of Toronto
| | - D. Cyril D’Souza
- Yale University, Department of Psychiatry, CAMH and University of Toronto,VACHS, Department of Psychiatry, CAMH and University of Toronto
| | | | | | | | - Kelly P. Cosgrove
- Yale University, Department of Psychiatry, CAMH and University of Toronto,VACHS, Department of Psychiatry, CAMH and University of Toronto
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Tonstad S, Heggen E, Giljam H, Lagerbäck PÅ, Tønnesen P, Wikingsson LD, Lindblom N, de Villiers S, Svensson TH, Fagerström KO. Niccine®, a nicotine vaccine, for relapse prevention: a phase II, randomized, placebo-controlled, multicenter clinical trial. Nicotine Tob Res 2013; 15:1492-501. [PMID: 23471101 DOI: 10.1093/ntr/ntt003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
INTRODUCTION A nicotine vaccine could prevent relapse to smoking by hindering blood nicotine from reaching the brain. Niccine® is a nicotine hapten tetanus-toxoid conjugate vaccine. The present study evaluated the clinical efficacy of Niccine for tobacco smoking relapse prevention. METHODS Cigarette smokers (n = 355) aged 25-50 years were enrolled in a randomized, double-blind, parallel group 1-year trial encompassing 16 visits and 16 telephone calls. Niccine 40 μg or placebo was administered on Days 0, 28, 56, 90, 150, and 210. Between Days 56-98, subjects were treated with varenicline to aid cessation, targeted for Day 70. Only individuals abstinent between Days 90-98 (n = 265) were allowed to continue to 1 year (n = 219). Relapse to smoking was defined as >5 cigarettes within 7 days or since the last contact, or smoking on >5 occasions within 7 days or since the last contact. RESULTS At 1 year, nonrelapse was 43.3% in the Niccine versus 51.1% in the placebo groups (difference = -7.9%; 95% CI = -20.6% to 4.9%). There was no benefit of Niccine on smoking status at 6 or 9 months, exhaled carbon monoxide levels, time to relapse, abstinence, withdrawal symptoms, or smoking reinforcement. Nicotine antibody levels increased (mean = 1.34 μg/ml; SD = 2.84 μg/ml) in the Niccine group, but were not related to relapse. Adverse events except hypersensitivity and compensatory smoking did not differ between groups. CONCLUSIONS This nicotine vaccine appeared well tolerated but did not influence trajectories of relapse possibly because of insufficient antibody levels or lack of efficacy of the vaccine concept for relapse prevention.
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Affiliation(s)
- Serena Tonstad
- Department of Preventive Cardiology, Oslo University Hospital Ullevål, Norway.
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5
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Raupach T, Hoogsteder PHJ, Onno van Schayck CP. Nicotine vaccines to assist with smoking cessation: current status of research. Drugs 2012; 72:e1-16. [PMID: 22356293 PMCID: PMC3702960 DOI: 10.2165/11599900-000000000-00000] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Tobacco smoking causes cardiovascular, respiratory and malignant disease, and stopping smoking is among the key medical interventions to lower the worldwide burden of these disorders. However, the addictive properties of cigarette smoking, including nicotine inhalation, render most quit attempts unsuccessful. Recommended therapies, including combinations of counselling and medication, produce long-term continuous abstinence rates of no more than 30%. Thus, more effective treatment options are needed. An intriguing novel therapeutic concept is vaccination against nicotine. The basic principle of this approach is that, after entering the systemic circulation, a substantial proportion of nicotine can be bound by antibodies. Once bound to antibodies, nicotine is no longer able to cross the blood-brain barrier. As a consequence, the rewarding effects of nicotine are diminished, and relapse to smoking is less likely to occur. Animal studies indicate that antibodies profoundly change the pharmacokinetics of the drug and can interfere with nicotine self-administration and impact on the severity of withdrawal symptoms. To date, five phase I/II clinical trials using vaccines against nicotine have been published. Results have been disappointing in that an increase in quit rates was only observed in small groups of smokers displaying particularly high antibody titres. The failure of encouraging preclinical data to completely translate to clinical studies may be partially explained by shortcomings of animal models of addiction and an incomplete understanding of the complex physiological and behavioural processes contributing to tobacco addiction. This review summarizes the current status of research and suggests some directions for the future development of vaccines against nicotine. Ideally, these vaccines could one day become part of a multifaceted approach to treating tobacco addiction that includes counselling and pharmacotherapy.
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Affiliation(s)
- Tobias Raupach
- Department of Cardiology and Pneumology, University Hospital Göttingen, Göttingen, Germany.
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LeSage MG, Shelley D, Pravetoni M, Pentel PR. Enhanced attenuation of nicotine discrimination in rats by combining nicotine-specific antibodies with a nicotinic receptor antagonist. Pharmacol Biochem Behav 2012; 102:157-62. [PMID: 22503967 DOI: 10.1016/j.pbb.2012.03.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/23/2012] [Accepted: 03/28/2012] [Indexed: 11/24/2022]
Abstract
Tobacco addiction requires activation by nicotine of a variety of central nicotinic acetylcholine receptors (nAChRs). In animals, both nAChR antagonists and immunization against nicotine can reduce nAChR activation by nicotine and block a variety of addiction-relevant behaviors. However, clinical use of nAChR antagonists for smoking cessation is limited by dose-related side effects, and immunization does not reliably produce sufficient antibody levels in smokers to enhance smoking cessation rates. Combining these approaches may be one way of addressing the limitations of each while enhancing overall efficacy. This study examined the individual and combined effects of passive immunization with the monoclonal nicotine-specific antibody Nic311 and the nicotinic receptor antagonist mecamylamine (MEC) on nicotine's discriminative stimulus effects. Rats were trained to discriminate 0.4 mg/kg of nicotine from saline using a two-lever operant discrimination procedure. Antagonism of nicotine discrimination by Nic311 (160 mg/kg i.v.) and ascending doses of MEC (0.03, 0.1, 0.3, and 1.0 mg/kg s.c.) was assessed across four consecutive daily 2-min extinction test sessions using a 2×2 design. Nic311 alone produced a 24-48% reduction in % nicotine-lever responding (%NLR) across all four test sessions. MEC produced a dose-dependent decrease in %NLR, with no effect at the two lowest doses and 80-93% attenuation at the two highest doses. Nic311 combined with MEC significantly suppressed %NLR at every MEC dose (85-92% reduction across all four test sessions). Very low doses of MEC that were ineffective alone completely blocked nicotine discrimination when combined with Nic311. These data demonstrate that nicotine-specific antibodies and MEC can work synergistically to suppress the subjective effects of nicotine and suggest that low doses of MEC may significantly enhance the efficacy of immunotherapy.
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Affiliation(s)
- Mark G LeSage
- Department of Medicine, Minneapolis Medical Research Foundation, Minneapolis, MN, United States.
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Hatsukami DK, Jorenby DE, Gonzales D, Rigotti NA, Glover ED, Oncken CA, Tashkin DP, Reus VI, Akhavain RC, Fahim REF, Kessler PD, Niknian M, Kalnik MW, Rennard SI. Immunogenicity and smoking-cessation outcomes for a novel nicotine immunotherapeutic. Clin Pharmacol Ther 2011; 89:392-9. [PMID: 21270788 PMCID: PMC4106715 DOI: 10.1038/clpt.2010.317] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
NicVAX®, a nicotine vaccine (3’AmNic-rEPA), has been clinically evaluated to determine if higher antibody concentrations are associated with higher smoking abstinence rates and if doses and frequency of administration are associated with increased antibody response. This randomized, double-blinded, placebo-controlled multicenter clinical trial (N=301 smokers) tested 200 and 400 µg doses administered 4 or 5 times over 6 months compared to placebo. 3’AmNic-rEPA recipients with the highest serum anti-nicotine antibody response (top 30% by AUC) were significantly more likely to attain 8 weeks continuous abstinence from weeks 19 through 26 than the placebo recipients (24.6% vs. 12.0%, p=0.024, OR=2.69, 95% CI, 1.14–6.37). The 5 injection 400 µg dose regimen had the greatest antibody response and had significantly higher abstinence rates than placebo. This study demonstrates proof-of-concept that 3’AmNic-rEPA elicits antibodies to nicotine and is associated with higher continuous abstinence rates, justifying its further development as a treatment for nicotine dependence.
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Affiliation(s)
- D K Hatsukami
- Department of Psychiatry, University of Minnesota Tobacco Use Programs, Minneapolis, Minnesota, USA.
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Malin DH, Moon WD, Goyarzu P, Magallanes N, Blair MB, Alexander MR, McDavid L, Spurgeon JL, Ennifar S, Fattom A. Passive immunization against nicotine attenuates somatic nicotine withdrawal syndrome in the rat. Nicotine Tob Res 2010; 12:438-44. [PMID: 20203107 DOI: 10.1093/ntr/ntq021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
INTRODUCTION Nicotine immunization is under consideration as an intervention for smoking cessation. Therefore, it was of interest to evaluate the effects of nicotine antibodies on the withdrawal syndrome following termination of chronic nicotine administration. METHODS Experiment 1 determined whether passive immunization following continuous nicotine infusion would alter the intensity of nicotine withdrawal syndrome in the rat. Fourteen rats were rendered nicotine dependent by 7 days of subcutaneous nicotine bitartrate infusion. On the final day, seven rats received 150 mg intraperitoneal (i.p.) of immune gamma globulin (IgG) raised against 3'-aminomethylnicotine-recombinant Pseudomonas aeruginosa exoprotein A (NicVAX, Nabi Biopharmaceuticals, Rockville, MD) and seven rats received normal IgG. Rats were observed under blind conditions for somatically expressed nicotine abstinence signs immediately prior to drug termination and at 12, 24, and 36 hr afterward. In Experiment 2, similarly treated rats were observed at 6- and 72-hr postwithdrawal, to test the possibility that immunization altered the time course rather than the intensity of withdrawal syndrome. Experiment 3 tested whether immunized rats were still nicotine dependent. Without pump removal, each rat was challenged by 1/mg/kg mecamylamine HCl and observed for precipitated withdrawal syndrome. RESULTS In Experiment 1, there was no premature withdrawal syndrome during nicotine infusion. After termination, the immunized group had significantly fewer withdrawal signs than controls. Experiment 2 showed that immunization did not simply alter the timing of the nicotine abstinence syndrome since immunization did not increase signs before or after the usual withdrawal timeframe. In Experiment 3, rats immunized on the final day of infusion were still nicotine dependent since they exhibited a vigorous mecamylamine-precipitated withdrawal syndrome. DISCUSSION Nicotine antibodies did not precipitate a withdrawal syndrome, and they markedly reduced the severity of spontaneous nicotine withdrawal. The present data suggests that this may be most readily explained by their reported delay of nicotine clearance.
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Affiliation(s)
- David H Malin
- University of Houston-Clear Lake, 2700 Bay Area Blvd., Houston, TX 77058, USA.
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9
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Abstract
Cigarette smoking remains an important risk factor for premature cardiovascular disease and its many complications. There are clear benefits from treating tobacco dependence on the rate of clinical outcomes. In addition to behavioral therapies, various pharmacologic strategies have been developed to help achieve this goal. First-line therapies include nicotine replacement, bupropion and varenicline, a partial nicotine antagonist. Second-line treatments include clonidine and nortriptyline. Additional treatment strategies with less proven efficacy include monoamine oxidase inhibitors, selective serotonin reuptake inhibitors, opioid receptor antagonists, bromocriptine, anti-anxiety drugs, nicotinic receptor antagonists (e.g. mecamylamine) and glucose tablets. Various approaches under investigation include inhibitors of the hepatic P450 enzyme (e.g. methoxsalen), cannabinoid-1 receptor antagonists (e.g. rimonabant), and nicotine vaccines.
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Affiliation(s)
- William H. Frishman
- Department of Medicine, New York Medical College and Westchester Medical Center, Valhalla, NY, USA,
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10
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Abstract
Simple, rapid and inexpensive rodent models of nicotine physical dependence and withdrawal syndrome have proved useful for preliminary screening of smoking cessation treatments. They have led to an exponential increase of knowledge regarding the underlying neurobiological mechanisms of dependence and withdrawal syndrome. The human nicotine withdrawal syndrome in smoking cessation is variable and multidimensional, involving irritability, anxiety, depression, cognitive and attentional impairments, weight gain, sleep disturbances, and craving for nicotine. Aside from sleep disturbances, analogous phenomena have been seen in rodent models using different measures of withdrawal intensity. It appears likely that different withdrawal phenomena may involve some partially divergent mechanisms. For example, depression-like phenomena may involve alterations in mechanisms such as the mesolimbic dopamine pathway from the ventral tegmental area to the nucleus accumbens. Irritability and anxiety may involve alterations in endogenous opioid systems and other regions, such as the amygdala. This chapter reviews many additional anatomical, neurochemical, and developmental elements that impact nicotine physical dependence.
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Gentry WB, Rüedi-Bettschen D, Owens SM. Development of active and passive human vaccines to treat methamphetamine addiction. HUMAN VACCINES 2009; 5:206-13. [PMID: 19276653 PMCID: PMC2741685 DOI: 10.4161/hv.5.4.7456] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Methamphetamine (METH) abuse is a major worldwide epidemic, with no specific medications for treatment of chronic or acute effects. Anti-METH antibodies have the potential to save lives and reduce the crippling effects of METH abuse. While they are not expected to be the magic bullet to immediately cure addiction, immunotherapy could provide a breakthrough medication to continuously block or attenuate METH effects during a comprehensive addiction recovery plan. A unique challenge for METH antibody antagonists is the need to protect the brain from the complex direct and indirect adverse effects of long-term METH use. To meet this challenge, a new generation of passive monoclonal antibodies and active immunization therapies are at an advanced stage of preclinical development. Both of these vaccines could play an essential role in a well planned recovery program from human METH addiction by providing long-lasting protection from the rewarding and reinforcing effect of METH.
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Affiliation(s)
- W Brooks Gentry
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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12
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Abstract
Behavioral discrimination procedures clearly demonstrate that nicotine elicits interoceptive stimulus effects in humans that are malleable by various pharmacological manipulations as well as by some behavioral manipulations. The parameters of nicotine discrimination and both chronic and acute factors that may alter discrimination behavior are addressed in this chapter, which emphasizes research by the author involving nicotine delivered by nasal spray. Human discrimination of nicotine is centrally mediated, as the central and peripheral nicotine antagonist mecamylamine blocks discrimination but the peripheral antagonist trimethaphan does not. The threshold dose for discrimination of nicotine via spray appears to be very low in smokers as well as nonsmokers. Because smoked tobacco delivers nicotine more rapidly than spray, the threshold dose of nicotine via smoking is probably even lower. In terms of individual differences, smokers may become tolerant to the discriminative stimulus effects of higher nicotine doses but not of low doses. Men may be more sensitive than women to nicotine's discriminative stimulus effects, consistent with other research suggesting that nicotine is more reinforcing in men than in women. Other potential individual differences in nicotine discrimination have not been clearly tested, but may include genetics, obesity, and dependence on other drugs. Acute environmental factors that alter nicotine discrimination include the specific training and testing conditions, pointing to the need for careful control over such conditions during research. Other factors, such as concurrent acute use of alcohol or caffeine, do not appear to alter nicotine discrimination, suggesting that changes in nicotine discrimination are not likely explanations for the association of smoking behavior with use of those drugs. Concurrent physical activity also does not appear to alter nicotine discrimination, indicating that results from studies of discrimination in subjects at quiet rest, the standard approach in this research, generalize well to discrimination in subjects engaged in various activities, as often occurs in the natural environment. Future research should more clearly examine the potential role of nicotine's discriminative stimulus effects in nicotine reinforcement and determine the generalizability of these findings to nicotine delivered by other means, particularly tobacco smoking.
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Affiliation(s)
- Kenneth A Perkins
- Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA 15213, USA.
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Abstract
Tobacco dependence is a chronic relapsing disease that needs continuous treatment. In combination with behavioural support, pharmacotherapy is a proven key component for supporting smoking cessation. Effective drugs are available and recommended: nicotine replacement therapy (NRT), bupropion and varenicline. Much research into new pharmacological approaches is ongoing, combining 'old' and 'new' drugs and personalizing a pharmacological treatment for a single smoker/patient; other new medications and vaccines are in development. Overall, pharmacotherapy seems to have efficacy and cost-effectiveness in real life, thus physicians should become familiar with these medicines. Further efforts should be aimed at optimizing treatment management and increasing smoking cessation rates in the general population.
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Affiliation(s)
- Laura Carrozzi
- Cardio-Thoracic Department, University Hospital of Pisa, Pisa, Italy.
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Keyler DE, Roiko SA, Earley CA, Murtaugh MP, Pentel PR. Enhanced immunogenicity of a bivalent nicotine vaccine. Int Immunopharmacol 2008; 8:1589-94. [PMID: 18656557 DOI: 10.1016/j.intimp.2008.07.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Revised: 06/30/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
Abstract
The efficacy of nicotine vaccines for smoking cessation is dependent upon their ability to elicit sufficiently high serum antibody concentrations. This study compared two nicotine immunogens representing different hapten presentations, 3'-aminomethyl nicotine conjugated to recombinant Pseudomonas exoprotein A (3'-AmNic-rEPA) and 6-carboxymethlureido nicotine conjugated to keyhole limpet hemocyanin (6-CMUNic-KLH), and assessed whether their concurrent administration would produce additive serum antibody concentrations in rats. Effects of vaccination on nicotine pharmacokinetics were also studied. Vaccination of rats with these immunogens produced non cross-reacting nicotine-specific antibodies (NicAb). Serum NicAb concentrations elicited by each individual immunogen were not affected by whether the immunogens were administered alone as monovalent vaccines or together as a bivalent vaccine. The total NicAb concentration in the bivalent vaccine group was additive compared to that of the monovalent vaccines alone. Higher serum NicAb concentrations, irrespective of which immunogen elicited the antibodies, were associated with greater binding of nicotine in serum, a lower unbound nicotine concentration in serum, and lower brain nicotine concentration. These results demonstrate that it is possible to design immunogens which provide distinct nicotine epitopes for immune presentation, and which produce additive serum antibody levels. The concurrent administration of these immunogens as a bivalent vaccine may provide a general strategy for enhancing the antibody response to small molecules such as nicotine.
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Affiliation(s)
- D E Keyler
- Minneapolis Medical Research Foundation, Minneapolis, MN, United States
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15
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Keyler DE, Lesage MG, Dufek MB, Pentel PR. Changes in maternal and fetal nicotine distribution after maternal administration of monoclonal nicotine-specific antibody to rats. Int Immunopharmacol 2006; 6:1665-72. [PMID: 16979120 PMCID: PMC2727278 DOI: 10.1016/j.intimp.2006.06.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Accepted: 06/30/2006] [Indexed: 11/19/2022]
Abstract
Vaccination against nicotine to elicit the production of nicotine-specific antibodies is a potential treatment for tobacco addiction which reduces nicotine distribution from serum to brain. Vaccination of pregnant rats also reduces the distribution of maternally-administered nicotine to the fetal brain. Whether this is due to maternal antibody reducing the transfer of nicotine from mother to fetus, or to fetal antibody altering the distribution of nicotine within the fetus, is not clear. In the current study, passive immunization of rats with the murine monoclonal nicotine-specific antibody Nic311 was used as a surrogate for vaccination because antibody transfer to the fetus was anticipated to be lower than with vaccination. Pregnant rats received nicotine from gestational day (GD) 18-20 as frequent i.v. boluses to simulate nicotine exposure from smoking. Nic311 was administered at doses of 30, 80 or 240 mg/kg on GD 19. Fetal serum Nic311 levels on GD 20 were <3% of concurrent maternal levels, but concentrations of up to 20 ug/ml in fetal serum were obtained owing to the very high levels in maternal serum. Accumulation of the chronically administered nicotine, measured on GD 20, was not changed by Nic311 treatment in either maternal or fetal brain. The early distribution of nicotine to maternal brain, measured 5 min after a dose, was markedly reduced by Nic311, while the early distribution of nicotine to whole fetus and fetal brain was not substantially altered. These data suggest that the limited transfer of Nic311 to the fetus in turn limits the ability of Nic311 to reduce nicotine distribution to the fetal brain.
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Affiliation(s)
- D E Keyler
- College of Pharmacy, University of Minnesota Minneapolis, MN, United States; Minneapolis Medical Research Foundation, Minneapolis, MN, United States
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16
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LeSage MG, Keyler DE, Hieda Y, Collins G, Burroughs D, Le C, Pentel PR. Effects of a nicotine conjugate vaccine on the acquisition and maintenance of nicotine self-administration in rats. Psychopharmacology (Berl) 2006; 184:409-16. [PMID: 15991003 DOI: 10.1007/s00213-005-0027-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 04/15/2005] [Indexed: 10/25/2022]
Abstract
RATIONALE Immunization of rats against nicotine using a nicotine conjugate vaccine reduces the distribution of nicotine to brain in rats and attenuates some of nicotine's physiological and behavioral effects. It is not known whether such a vaccine can attenuate nicotine's reinforcing effects. OBJECTIVE The present experiment was conducted to determine whether a nicotine conjugate vaccine could interfere with the acquisition and maintenance of nicotine self-administration (NSA) in rats given 23 h day(-1) access to nicotine. METHODS To examine acquisition of NSA, rats were vaccinated with nicotine or control immunogen prior to being given access to a 0.01 mg kg(-1) infusion(-1) nicotine under a fixed-ratio(FR) 1 schedule for week 1, FR 2 for week 2, and FR 3 for week 3. Acquisition of cocaine self-administration (CSA) was similarly examined to determine the specificity of vaccination effects. To examine maintenance of NSA, rats were initially trained to self-administer nicotine under an FR 3 schedule, and then vaccinated with nicotine or control immunogen while NSA continued to be monitored. RESULTS NSA was significantly lower in vaccinated rats compared to controls during the acquisition protocol, with a 38% decrease in the number of infusions during the last week of training. The percentage of rats meeting acquisition criteria in the vaccinated group was lower (36%) than that in the control group (70%), but this difference was not statistically significant. Vaccination did not affect acquisition of CSA, demonstrating its specificity for nicotine. Maintenance of NSA was significantly reduced in vaccinated rats as compared to controls after the final vaccine injection, with a mean reduction of 57%. There was no evidence in either protocol that vaccinated rats attempted to compensate for altered nicotine distribution by increasing nicotine intake. CONCLUSION These data suggest that vaccination against nicotine can reduce the reinforcing effects of nicotine in rats and may have therapeutic potential for the treatment of tobacco dependence.
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Affiliation(s)
- Mark G LeSage
- Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
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LeSage MG, Keyler DE, Pentel PR. Current status of immunologic approaches to treating tobacco dependence: vaccines and nicotine-specific antibodies. AAPS JOURNAL 2006; 8:E65-75. [PMID: 16584135 PMCID: PMC3889506 DOI: 10.1208/aapsj080108] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In contrast to current pharmacotherapies, immunologic approaches to treating tobacco dependence target the drug itself rather than the brain. This approach involves the use of nicotine-specific antibodies that bind nicotine in serum, resulting in a decrease in nicotine distribution to the brain and an increase in nicotine's elimination half-life. This review summarizes the literature examining the effects of immunologic interventions on the pharmacokinetics and behavioral effects of nicotine in animal models, as well as recent phase I and II clinical trials in humans. Studies using various vaccines and nicotine-specific antibodies in rodents have shown that immunization can significantly reduce the behavioral effects of nicotine that are relevant to tobacco dependence (eg, nicotine self-administration). These findings provide proof of principle that immunologic interventions could have utility in the treatment of tobacco dependence. Thus far, phase I clinical trials of nicotine vaccines have not produced any serious adverse events in humans and have produced dose-dependent increases in serum antibody levels. Although preliminary data from these small trials suggest that vaccination can facilitate abstinence from tobacco use, more advance trials are needed. By acting outside the nervous system, immunologic approaches are less likely to produce the adverse side effects associated with current medications. In addition, the unique mechanism of action of immunotherapy makes it particularly suitable for combination with other pharmacological approaches. Taken together, the work completed to date provides substantial evidence that immunologic interventions could play an important role in future treatment strategies for tobacco dependence.
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Affiliation(s)
- Mark G LeSage
- Minneapolis Medical Research Foundation, Department of Medicine, University of Minnesota Medical School, Minneapolis, USA.
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Pentel PR, Dufek MB, Roiko SA, Lesage MG, Keyler DE. Differential effects of passive immunization with nicotine-specific antibodies on the acute and chronic distribution of nicotine to brain in rats. J Pharmacol Exp Ther 2006; 317:660-6. [PMID: 16407464 DOI: 10.1124/jpet.105.097873] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vaccination against nicotine blocks or attenuates nicotine-related behaviors relevant to addiction in rats. Passive immunization with nicotine-specific antibodies is an alternative to vaccination with the potential advantages of allowing control of antibody dose and affinity. In the current study, the effects of two antibodies on the distribution of nicotine to brain were evaluated during chronic nicotine administration in rats; the monoclonal antibody Nic311 (K(d) = 60 nM) and nicotine-specific antiserum (K(d) = 1.6 nM). Nicotine was administered via repeated i.v. bolus doses over 2 days and antibody was administered during the first day. Neither antibody appreciably reduced the chronic accumulation of nicotine in brain, despite high protein binding of nicotine in serum (98.9%) and a 73% reduction in the unbound serum nicotine concentration with the highest Nic311 dose. However, both antibodies substantially reduced the early distribution of nicotine to brain 5 min after a dose. The higher affinity antibody was no more effective than Nic311. The highest Nic311 dose produced serum antibody levels 10 times higher than those reported with vaccination. The efficacy of Nic311 was dose-related, with the highest dose producing a 76% decrease in the early distribution of nicotine to brain. These findings, along with previous data, suggest that the primary effect of passive immunization is to slow, rather than prevent, the distribution of nicotine to brain. In the setting of chronic nicotine dosing, antibodies with a moderate affinity for nicotine produced substantial effects on the early distribution of nicotine to brain and were as effective as higher affinity antibodies.
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Affiliation(s)
- P R Pentel
- Department of Medicine, University of Minnesota, Minneapolis, Minnesota 55422, USA.
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19
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Kosten T, Owens SM. Immunotherapy for the treatment of drug abuse. Pharmacol Ther 2006; 108:76-85. [PMID: 16023218 DOI: 10.1016/j.pharmthera.2005.06.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Accepted: 06/07/2005] [Indexed: 11/28/2022]
Abstract
Antibody therapy (as either active or passive immunization) is designed primarily to prevent drugs of abuse from entering the central nervous system (CNS). Antidrug antibodies reduce rush, euphoria, and drug distribution to the brain at doses that exceed the apparent binding capacity of the antibody. This is accomplished through a pharmacokinetic antagonism, which reduces the amount of drug in the brain, the rate of clearance across the blood-brain barrier, and the volume of drug distribution. Because the antibodies remain primarily in the circulatory system, they have no apparent central nervous system side effects. Active immunization with drug-protein conjugate vaccines has been tested for cocaine, heroin, methamphetamine, and nicotine in animal, with 1 cocaine and 3 nicotine vaccines in Phase 2 human trials. Passive immunization with high affinity monoclonal antibodies has been tested for cocaine, methamphetamine, nicotine, and phencyclidine (PCP) in preclinical animal models. Antibodies have 2 immediate clinical applications in drug abuse treatment: to treat drug overdose and to reduce relapse to drug use in addicted patients. The specificity of the therapies, the lack of addiction liability, minimal side effects, and long-lasting protection against drug use offer major therapeutic benefit over conventional small molecule agonists and antagonists. Immunotherapies can also be combined with other antiaddiction medications and enhance behavioral therapies. Current immunotherapies already show efficacy, but improved antigen design and antibody engineering promise highly specific and rapidly developed treatments for both existing and future addictions.
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Affiliation(s)
- Thomas Kosten
- Yale School of Medicine, Department of Psychiatry, West Haven, CT 06516, USA.
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20
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Keyler DE, Dufek MB, Calvin AD, Bramwell TJ, LeSage MG, Raphael DE, Ross CA, Le CT, Pentel PR. Reduced nicotine distribution from mother to fetal brain in rats vaccinated against nicotine: Time course and influence of nicotine dosing regimen. Biochem Pharmacol 2005; 69:1385-95. [PMID: 15826609 DOI: 10.1016/j.bcp.2005.02.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 02/02/2005] [Indexed: 11/22/2022]
Abstract
Nicotine is a teratogen in rats and possibly in humans. Vaccination against nicotine is being studied as a possible treatment for nicotine dependence. The safety of maternal vaccination against nicotine during or prior to pregnancy is not known. In this study, female rats were vaccinated and then administered acute or chronic nicotine during pregnancy at doses simulating nicotine exposure in smokers. Maternal vaccination reduced nicotine distribution to both maternal brain (44-47%) and fetal brain (17-39%) for up to 25 min after a single maternal nicotine dose administered on gestational day (GD) 20, but had a smaller effect on nicotine distribution to brain after continuous nicotine infusion. Nicotine distribution to maternal or fetal brain after repeated nicotine bolus doses was reduced immediately following an individual dose in vaccinated rats, but the chronic accumulation of nicotine in fetal brain was not altered. Nicotine distribution to whole fetus, in contrast to fetal brain, was generally not altered by vaccination. Nicotine-specific antibody concentration in fetal serum was 10% that of maternal serum, and in fetal brain was <1% of maternal serum. Although nicotine transfer to the whole fetus was not reduced by vaccination, protein binding data suggest that nicotine-specific antibody transferred from mother to fetus served to bind nicotine in fetal serum, reduce the unbound nicotine concentration, and thereby reduce nicotine distribution to fetal brain. These data comment on the safety of vaccination against nicotine during pregnancy, and suggest that vaccination may reduce the distribution of nicotine to fetal brain under some nicotine dosing conditions.
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Affiliation(s)
- Daniel E Keyler
- Minneapolis Medical Research Foundation, Hennepin County Medical Center, Minneapolis, MN 55415, USA
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21
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Keyler DE, Roiko SA, Benlhabib E, LeSage MG, St Peter JV, Stewart S, Fuller S, Le CT, Pentel PR. Monoclonal nicotine-specific antibodies reduce nicotine distribution to brain in rats: dose- and affinity-response relationships. Drug Metab Dispos 2005; 33:1056-61. [PMID: 15843487 DOI: 10.1124/dmd.105.004234] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vaccination against nicotine is being studied as a potential treatment for nicotine dependence. Some of the limitations of vaccination, such as variability in antibody titer and affinity, might be overcome by instead using passive immunization with nicotine-specific monoclonal antibodies. The effects of antibodies on nicotine distribution to brain were studied using nicotine-specific monoclonal antibodies (NICmAbs) with K(d) values ranging from 60 to 250 nM and a high-affinity polyclonal rabbit antiserum (K(d) = 1.6 nM). Pretreatment with NICmAbs substantially increased the binding of nicotine in serum after a single nicotine dose, reduced the unbound nicotine concentration in serum, and reduced the distribution of nicotine to brain. Efficacy was directly related to antibody affinity for nicotine. Efficacy of the highest affinity NICmAb, NICmAb311, was dose-related, with the highest dose reducing nicotine distribution to brain by 78%. NICmAb311 decreased nicotine clearance by 90% and prolonged the terminal half-life of nicotine by 120%. At equivalent doses, NICmAb311 was less effective than the higher affinity rabbit antiserum but comparable efficacy could be achieved by increasing the NICmAb311 dose. These data suggest that passive immunization with nicotine-specific monoclonal antibodies substantially alters nicotine pharmacokinetics in a manner similar to that previously reported for vaccination against nicotine. Antibody efficacy is a function of both dose and affinity for nicotine.
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Affiliation(s)
- D E Keyler
- Minneapolis Medical Research Foundation, Minnesota, USA
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22
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Carrera MRA, Ashley JA, Hoffman TZ, Isomura S, Wirsching P, Koob GF, Janda KD. Investigations using immunization to attenuate the psychoactive effects of nicotine. Bioorg Med Chem 2004; 12:563-70. [PMID: 14738965 DOI: 10.1016/j.bmc.2003.11.029] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Despite the enormous health risks, people continue to smoke and use tobacco primarily as a result of nicotine addiction. As part of our immunopharmacotherapy research, the effects of active and passive immunizations on acute nicotine-induced locomotor activity in rats were investigated. To this end, rats were immunized with either a NIC-KLH immunoconjugate vaccine designed to elicit an antinicotine immune response, or were administered an antinicotine monoclonal antibody, NIC9D9, prior to a series of nicotine challenges and testing sessions. Vaccinated rats showed a 45% decrease in locomotor activity compared to a 16% decrease in controls. Passive immunization with NIC9D9 resulted in a 66.9% decrease in locomotor activity versus a 3.4% decrease in controls. Consistent with the behavioral data, much less nicotine was found in the brains of immunized rats. The results support the potential clinical value of immunopharmacotherapy for nicotine addiction in the context of tobacco cessation programs.
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Affiliation(s)
- M Rocío A Carrera
- Department of Chemistry, The Scripps Research Institute and the Skaggs Institute for Chemical Biology, 10550N. Torrey Pines Road, La Jolla, CA 92037, USA
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23
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Laurenzana EM, Gunnell MG, Gentry WB, Owens SM. Treatment of adverse effects of excessive phencyclidine exposure in rats with a minimal dose of monoclonal antibody. J Pharmacol Exp Ther 2003; 306:1092-8. [PMID: 12829731 DOI: 10.1124/jpet.103.053140] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The range of medical effects and complications resulting from excessive use of drugs of abuse like phencyclidine (PCP) has hindered the development of effective medications. Drug-specific monoclonal antibodies (mAbs) provide an appealing medication approach since they can be selective for the drug, without concern for the sites of action of the drug. The use of mAb medications has been considered impractical because it is commonly believed that very large doses of mAb would be required to treat the adverse medical effects resulting from excessive drug use. In this study, a single dose of an anti-PCP mAb was found to significantly reduce the negative health impact of excessive, prolonged PCP treatment in rats (18 mg/kg/day for 2 weeks). The protective effects were mAb dose-dependent, and mAb doses as low as 1/100th the molar equivalent amount of the PCP body burden were effective at preventing PCP-induced deaths, reducing PCP-induced behaviors, reducing PCP brain concentrations, and improving the general health status of the animals. They also show that treatment with monoclonal antibody medications can have medically important outcomes without the need to neutralize the entire dose of the offending drug. These results could help establish the feasibility of using carefully designed monoclonal antibody medications to treat drug abuse and addiction, a chronic and re-occurring illness of the central nervous system.
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Affiliation(s)
- Elizabeth M Laurenzana
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Satoskar SD, Keyler DE, LeSage MG, Raphael DE, Ross CA, Pentel PR. Tissue-dependent effects of immunization with a nicotine conjugate vaccine on the distribution of nicotine in rats. Int Immunopharmacol 2003; 3:957-70. [PMID: 12810353 DOI: 10.1016/s1567-5769(03)00094-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vaccination of rats against nicotine reduces nicotine distribution to brain even at nicotine doses greatly exceeding the estimated binding capacity of the available antibody. This observation suggests a differential effect by which vaccination reduces nicotine distribution to brain to a greater extent than to other tissues. To test this hypothesis, vaccinated rats received a single intravenous nicotine dose equal to twice the estimated binding capacity of nicotine-specific antibody in vaccinated rats. The total and bound serum nicotine concentrations were higher in the vaccinated rats compared to controls, while the unbound serum nicotine concentration was lower. Distribution of nicotine to brain was reduced in vaccinated rats in a time-dependent manner, with a greater reduction at 1 min (64%) than at 25 min (45%). Vaccination reduced nicotine distribution to muscle, testis, spleen, liver, heart, and kidney, but to a lesser extent than to brain, while nicotine distribution to fat was increased. Chronically infused nicotine showed a similarly altered pattern of tissue distribution in vaccinated rats, but differences were in general smaller than after a single nicotine dose; brain nicotine concentration was 24% lower in vaccinated rats, while lung nicotine concentration was higher. The presence of nicotine-specific antibody in tissues may have contributed to the increased nicotine concentrations in fat and lung. These data suggest that vaccination reduces nicotine distribution to brain not only by sequestering nicotine in serum but also by redirecting tissue distribution disproportionately away from brain, such that nicotine concentrations are reduced to a greater extent in brain than in other tissues.
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Affiliation(s)
- S D Satoskar
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA.
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Keyler DE, Shoeman D, LeSage MG, Calvin AD, Pentel PR. Maternal vaccination against nicotine reduces nicotine distribution to fetal brain in rats. J Pharmacol Exp Ther 2003; 305:587-92. [PMID: 12606612 DOI: 10.1124/jpet.102.046805] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cigarette smoking during pregnancy is associated with a variety of adverse fetal outcomes. Nicotine is a likely contributor to these adverse effects, with fetal brain as one target organ. Vaccination of adult male rats against nicotine has been shown to reduce nicotine distribution to the brain. The current study examined whether vaccination of female rats before pregnancy would reduce the distribution to fetal brain of a single nicotine dose administered during gestation. Female rats immunized with a nicotine conjugate vaccine received a single dose of nicotine 0.03 mg/kg i.v. on gestational day 16 to 22. Five minutes later, vaccinated rats had substantially higher bound and lower unbound serum nicotine concentration and lower brain nicotine concentration than controls. Fetal brain nicotine concentration was reduced by 43% in vaccinated rats, comparable to the reduction in the maternal brain nicotine concentration. The whole-fetus nicotine concentration was not altered by vaccination. A similar experiment was performed in which pregnant rats were passively immunized with rabbit nicotine-specific IgG 7 or 21 mg/kg just before nicotine dosing. The effects of passive immunization on nicotine distribution in the mother were IgG dose-related and the higher dose reduced nicotine distribution to fetal brain by 60%. These data suggest that vaccine effects on nicotine distribution to serum and brain are similar in pregnant female rats to those previously reported in adult males. Vaccination of female rats before pregnancy, or passive immunization during pregnancy, can reduce the exposure of fetal brain to a single dose of maternally administered nicotine.
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Affiliation(s)
- D E Keyler
- Department of Medicine, Hennepin County Medical Center, 701 Park Ave S., Minneapolis, MN 55415, USA
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